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Openbmc/wdt #5

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Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
We do the same reset procedure in apeed_wdt_enable and our reboot
notifier, so move these to a separate function.

Also, use a couple of definitions for the watchdog control value
rather than a hardcoded '3'.

Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Currently, the watchdog timer does nothing on expiry - the 'SoC system'
reset type doesn't seem to have any effect.

This change uses the 'full chip' reset type instead.

Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
@shenki
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shenki commented Oct 23, 2015

Still a bit concerned that we don't understand why we need the full chip reset, but happy to merge it as it makes the system much easier to use.

Merged.

@shenki shenki closed this Oct 23, 2015
@jk-ozlabs jk-ozlabs deleted the openbmc/wdt branch October 28, 2015 01:00
shenki pushed a commit that referenced this pull request Nov 13, 2015
…ap_device_late_init

Kernel fails to boot 50% of times (form build to build) with
RT-patchset applied due to the following race - on late boot
stages deferred_probe_work_func->omap_hsmmc_probe races with omap_device_late_ini.

The same issue has been reported now on linux-next (4.3) by Keerthy [1]

late_initcall
 - deferred_probe_initcal() tries to re-probe all pending driver's probe.

- later on, some driver is probing in this case It's cpsw.c
  (but could be any other drivers)
  cpsw_init
  - platform_driver_register
    - really_probe
       - driver_bound
         - driver_deferred_probe_trigger
  and boot proceed.
  So, at this moment we have deferred_probe_work_func scheduled.

late_initcall_sync
  - omap_device_late_init
    - omap_device_idle

CPU1					CPU2
  - deferred_probe_work_func
    - really_probe
      - omap_hsmmc_probe
	- pm_runtime_get_sync
					late_initcall_sync
					- omap_device_late_init
						if (od->_driver_status != BUS_NOTIFY_BOUND_DRIVER) {
							if (od->_state == OMAP_DEVICE_STATE_ENABLED) {
								- omap_device_idle [ops - IP is disabled]
	- [fail]
	- pm_runtime_put_sync
          - omap_hsmmc_runtime_suspend [ooops!]

== log ==
 omap_hsmmc 480b4000.mmc: unable to get vmmc regulator -517
 davinci_mdio 48485000.mdio: davinci mdio revision 1.6
 davinci_mdio 48485000.mdio: detected phy mask fffffff3
 libphy: 48485000.mdio: probed
 davinci_mdio 48485000.mdio: phy[2]: device 48485000.mdio:02, driver unknown
 davinci_mdio 48485000.mdio: phy[3]: device 48485000.mdio:03, driver unknown
 omap_hsmmc 480b4000.mmc: unable to get vmmc regulator -517
 cpsw 48484000.ethernet: Detected MACID = b4:99:4c:c7:d2:48
 cpsw 48484000.ethernet: cpsw: Detected MACID = b4:99:4c:c7:d2:49
 hctosys: unable to open rtc device (rtc0)
 omap_hsmmc 480b4000.mmc: omap_device_late_idle: enabled but no driver.  Idling
 ldousb: disabling
 Unhandled fault: imprecise external abort (0x1406) at 0x00000000
 [00000000] *pgd=00000000
 Internal error: : 1406 [#1] PREEMPT SMP ARM
 Modules linked in:
 CPU: 1 PID: 58 Comm: kworker/u4:1 Not tainted 4.1.2-rt1-00467-g6da3c0a-dirty #5
 Hardware name: Generic DRA74X (Flattened Device Tree)
 Workqueue: deferwq deferred_probe_work_func
 task: ee6ddb00 ti: edd3c000 task.ti: edd3c000
 PC is at omap_hsmmc_runtime_suspend+0x1c/0x12c
 LR is at _od_runtime_suspend+0xc/0x24
 pc : [<c0471998>]    lr : [<c0029590>]    psr: a0000013
 sp : edd3dda0  ip : ee6ddb00  fp : c07be540
 r10: 00000000  r9 : c07be540  r8 : 00000008
 r7 : 00000000  r6 : ee646c10  r5 : ee646c10  r4 : edd79380
 r3 : fa0b4100  r2 : 00000000  r1 : 00000000  r0 : ee646c10
 Flags: NzCv  IRQs on  FIQs on  Mode SVC_32  ISA ARM  Segment kernel
 Control: 10c5387d  Table: 8000406a  DAC: 00000015
 Process kworker/u4:1 (pid: 58, stack limit = 0xedd3c218)
 Stack: (0xedd3dda0 to 0xedd3e000)
 dda0: ee646c70 ee646c10 c0029584 00000000 00000008 c0029590 ee646c70 ee646c10
 ddc0: c0029584 c03adfb8 ee646c10 00000004 0000000c c03adff0 ee646c10 00000004
 dde0: 0000000c c03ae4ec 00000000 edd3c000 ee646c10 00000004 ee646c70 00000004
 de00: fa0b4000 c03aec20 ee6ddb00 ee646c10 00000004 ee646c70 ee646c10 fffffdfb
 de20: edd79380 00000000 fa0b4000 c03aee90 fffffdfb edd79000 ee646c00 c0474290
 de40: 00000000 edda24c0 edd79380 edc81f00 00000000 00000200 00000001 c06dd488
 de60: edda3960 ee646c10 ee646c10 c0824cc4 fffffdfb c0880c94 00000002 edc92600
 de80: c0836378 c03a7f84 ee646c10 c0824cc4 00000000 c0880c80 c0880c94 c03a6568
 dea0: 00000000 ee646c10 c03a66ac ee4f8000 00000000 00000001 edc92600 c03a4b40
 dec0: ee404c94 edc83c4c ee646c10 ee646c10 ee646c44 c03a63c4 ee646c10 ee646c10
 dee0: c0814448 c03a5aa8 ee646c10 c0814220 edd3c000 c03a5ec0 c0814250 ee6be400
 df00: edd3c000 c004e5bc ee6ddb01 00000078 ee6ddb00 ee4f8000 ee6be418 edd3c000
 df20: ee4f8028 00000088 c0836045 ee4f8000 ee6be400 c004e928 ee4f8028 00000000
 df40: c004e8ec 00000000 ee6bf1c0 ee6be400 c004e8ec 00000000 00000000 00000000
 df60: 00000000 c0053450 2e56fa97 00000000 afdffbd7 ee6be400 00000000 00000000
 df80: edd3df80 edd3df80 00000000 00000000 edd3df90 edd3df90 edd3dfac ee6bf1c0
 dfa0: c0053384 00000000 00000000 c000f668 00000000 00000000 00000000 00000000
 dfc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
 dfe0: 00000000 00000000 00000000 00000000 00000013 00000000 f1fc9d7e febfbdff
 [<c0471998>] (omap_hsmmc_runtime_suspend) from [<c0029590>] (_od_runtime_suspend+0xc/0x24)
 [<c0029590>] (_od_runtime_suspend) from [<c03adfb8>] (__rpm_callback+0x24/0x3c)
 [<c03adfb8>] (__rpm_callback) from [<c03adff0>] (rpm_callback+0x20/0x80)
 [<c03adff0>] (rpm_callback) from [<c03ae4ec>] (rpm_suspend+0xe4/0x618)
 [<c03ae4ec>] (rpm_suspend) from [<c03aee90>] (__pm_runtime_idle+0x60/0x80)
 [<c03aee90>] (__pm_runtime_idle) from [<c0474290>] (omap_hsmmc_probe+0x6bc/0xa7c)
 [<c0474290>] (omap_hsmmc_probe) from [<c03a7f84>] (platform_drv_probe+0x44/0xa4)
 [<c03a7f84>] (platform_drv_probe) from [<c03a6568>] (driver_probe_device+0x170/0x2b4)
 [<c03a6568>] (driver_probe_device) from [<c03a4b40>] (bus_for_each_drv+0x64/0x98)
 [<c03a4b40>] (bus_for_each_drv) from [<c03a63c4>] (device_attach+0x70/0x88)
 [<c03a63c4>] (device_attach) from [<c03a5aa8>] (bus_probe_device+0x84/0xac)
 [<c03a5aa8>] (bus_probe_device) from [<c03a5ec0>] (deferred_probe_work_func+0x58/0x88)
 [<c03a5ec0>] (deferred_probe_work_func) from [<c004e5bc>] (process_one_work+0x134/0x464)
 [<c004e5bc>] (process_one_work) from [<c004e928>] (worker_thread+0x3c/0x4fc)
 [<c004e928>] (worker_thread) from [<c0053450>] (kthread+0xcc/0xe4)
 [<c0053450>] (kthread) from [<c000f668>] (ret_from_fork+0x14/0x2c)
 Code: e594302c e593202c e584205c e594302c (e5932128)
 ---[ end trace 0000000000000002 ]---

The issue happens because omap_device_late_init() do not take into
account that some drivers are present, but their probes were not
finished successfully and where deferred instead. This is the valid
case, and omap_device_late_init() should not idle such devices.

To fix this issue, the value of omap_device->_driver_status field
should be checked not only for BUS_NOTIFY_BOUND_DRIVER (driver is
present and has been bound to device successfully), but also checked
for BUS_NOTIFY_BIND_DRIVER (driver about to be bound) - which means
driver is present and there was try to bind it to device.

[1] http://www.spinics.net/lists/arm-kernel/msg441880.html
Cc: Tero Kristo <t-kristo@ti.com>
Cc: Keerthy <j-keerthy@ti.com>
Tested-by: Keerthy <j-keerthy@ti.com>
Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
shenki pushed a commit that referenced this pull request Nov 13, 2015
The renesas-irqc interrupt controller is cascaded to the GIC. Hence when
propagating wake-up settings to its parent interrupt controller, the
following lockdep warning is printed:

    =============================================
    [ INFO: possible recursive locking detected ]
    4.2.0-ape6evm-10725-g50fcd7643c034198 torvalds#280 Not tainted
    ---------------------------------------------
    s2ram/1072 is trying to acquire lock:
    (&irq_desc_lock_class){-.-...}, at: [<c008d3fc>] __irq_get_desc_lock+0x58/0x98

    but task is already holding lock:
    (&irq_desc_lock_class){-.-...}, at: [<c008d3fc>] __irq_get_desc_lock+0x58/0x98

    other info that might help us debug this:
    Possible unsafe locking scenario:

	  CPU0
	  ----
     lock(&irq_desc_lock_class);
     lock(&irq_desc_lock_class);

    *** DEADLOCK ***

    May be due to missing lock nesting notation

    6 locks held by s2ram/1072:
    #0:  (sb_writers#7){.+.+.+}, at: [<c012eb14>] __sb_start_write+0xa0/0xa8
    #1:  (&of->mutex){+.+.+.}, at: [<c019396c>] kernfs_fop_write+0x4c/0x1bc
    #2:  (s_active#24){.+.+.+}, at: [<c0193974>] kernfs_fop_write+0x54/0x1bc
    #3:  (pm_mutex){+.+.+.}, at: [<c008213c>] pm_suspend+0x10c/0x510
    #4:  (&dev->mutex){......}, at: [<c02af3c4>] __device_suspend+0xdc/0x2cc
    #5:  (&irq_desc_lock_class){-.-...}, at: [<c008d3fc>] __irq_get_desc_lock+0x58/0x98

    stack backtrace:
    CPU: 0 PID: 1072 Comm: s2ram Not tainted 4.2.0-ape6evm-10725-g50fcd7643c034198 torvalds#280
    Hardware name: Generic R8A73A4 (Flattened Device Tree)
    [<c0018078>] (unwind_backtrace) from [<c00144f0>] (show_stack+0x10/0x14)
    [<c00144f0>] (show_stack) from [<c0451f14>] (dump_stack+0x88/0x98)
    [<c0451f14>] (dump_stack) from [<c007b29c>] (__lock_acquire+0x15cc/0x20e4)
    [<c007b29c>] (__lock_acquire) from [<c007c6e0>] (lock_acquire+0xac/0x12c)
    [<c007c6e0>] (lock_acquire) from [<c0457c00>] (_raw_spin_lock_irqsave+0x40/0x54)
    [<c0457c00>] (_raw_spin_lock_irqsave) from [<c008d3fc>] (__irq_get_desc_lock+0x58/0x98)
    [<c008d3fc>] (__irq_get_desc_lock) from [<c008ebbc>] (irq_set_irq_wake+0x20/0xf8)
    [<c008ebbc>] (irq_set_irq_wake) from [<c0260770>] (irqc_irq_set_wake+0x20/0x4c)
    [<c0260770>] (irqc_irq_set_wake) from [<c008ec28>] (irq_set_irq_wake+0x8c/0xf8)
    [<c008ec28>] (irq_set_irq_wake) from [<c02cb8c0>] (gpio_keys_suspend+0x74/0xc0)
    [<c02cb8c0>] (gpio_keys_suspend) from [<c02ae8cc>] (dpm_run_callback+0x54/0x124)

Avoid this false positive by using a separate lockdep class for IRQC
interrupts.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: Grygorii Strashko <grygorii.strashko@ti.com>
Cc: Magnus Damm <magnus.damm@gmail.com>
Cc: Jason Cooper <jason@lakedaemon.net>
Link: http://lkml.kernel.org/r/1441798974-25716-2-git-send-email-geert%2Brenesas@glider.be
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
shenki pushed a commit that referenced this pull request Nov 13, 2015
The renesas-intc-irqpin interrupt controller is cascaded to the GIC.
Hence when propagating wake-up settings to its parent interrupt
controller, the following lockdep warning is printed:

    =============================================
    [ INFO: possible recursive locking detected ]
    4.2.0-armadillo-10725-g50fcd7643c034198 torvalds#781 Not tainted
    ---------------------------------------------
    s2ram/1179 is trying to acquire lock:
    (&irq_desc_lock_class){-.-...}, at: [<c005bb54>] __irq_get_desc_lock+0x78/0x94

    but task is already holding lock:
    (&irq_desc_lock_class){-.-...}, at: [<c005bb54>] __irq_get_desc_lock+0x78/0x94

    other info that might help us debug this:
    Possible unsafe locking scenario:

	  CPU0
	  ----
     lock(&irq_desc_lock_class);
     lock(&irq_desc_lock_class);

    *** DEADLOCK ***

    May be due to missing lock nesting notation

    7 locks held by s2ram/1179:
    #0:  (sb_writers#7){.+.+.+}, at: [<c00c9708>] __sb_start_write+0x64/0xb8
    #1:  (&of->mutex){+.+.+.}, at: [<c0125a00>] kernfs_fop_write+0x78/0x1a0
    #2:  (s_active#23){.+.+.+}, at: [<c0125a08>] kernfs_fop_write+0x80/0x1a0
    #3:  (autosleep_lock){+.+.+.}, at: [<c0058244>] pm_autosleep_lock+0x18/0x20
    #4:  (pm_mutex){+.+.+.}, at: [<c0057e50>] pm_suspend+0x54/0x248
    #5:  (&dev->mutex){......}, at: [<c0243a20>] __device_suspend+0xdc/0x240
    #6:  (&irq_desc_lock_class){-.-...}, at: [<c005bb54>] __irq_get_desc_lock+0x78/0x94

    stack backtrace:
    CPU: 0 PID: 1179 Comm: s2ram Not tainted 4.2.0-armadillo-10725-g50fcd7643c034198

    Hardware name: Generic R8A7740 (Flattened Device Tree)
    [<c00129f4>] (dump_backtrace) from [<c0012bec>] (show_stack+0x18/0x1c)
    [<c0012bd4>] (show_stack) from [<c03f5d94>] (dump_stack+0x20/0x28)
    [<c03f5d74>] (dump_stack) from [<c00514d4>] (__lock_acquire+0x67c/0x1b88)
    [<c0050e58>] (__lock_acquire) from [<c0052df8>] (lock_acquire+0x9c/0xbc)
    [<c0052d5c>] (lock_acquire) from [<c03fb068>] (_raw_spin_lock_irqsave+0x44/0x58)
    [<c03fb024>] (_raw_spin_lock_irqsave) from [<c005bb54>] (__irq_get_desc_lock+0x78/0x94
    [<c005badc>] (__irq_get_desc_lock) from [<c005c3d8>] (irq_set_irq_wake+0x28/0x100)
    [<c005c3b0>] (irq_set_irq_wake) from [<c01e50d0>] (intc_irqpin_irq_set_wake+0x24/0x4c)
    [<c01e50ac>] (intc_irqpin_irq_set_wake) from [<c005c17c>] (set_irq_wake_real+0x3c/0x50
    [<c005c140>] (set_irq_wake_real) from [<c005c414>] (irq_set_irq_wake+0x64/0x100)
    [<c005c3b0>] (irq_set_irq_wake) from [<c02a19b4>] (gpio_keys_suspend+0x60/0xa0)
    [<c02a1954>] (gpio_keys_suspend) from [<c023b750>] (platform_pm_suspend+0x3c/0x5c)

Avoid this false positive by using a separate lockdep class for INTC
External IRQ Pin interrupts.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: Grygorii Strashko <grygorii.strashko@ti.com>
Cc: Magnus Damm <magnus.damm@gmail.com>
Cc: Jason Cooper <jason@lakedaemon.net>
Link: http://lkml.kernel.org/r/1441798974-25716-3-git-send-email-geert%2Brenesas@glider.be
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
shenki pushed a commit that referenced this pull request Nov 13, 2015
My colleague ran into a program stall on a x86_64 server, where
n_tty_read() was waiting for data even if there was data in the buffer
in the pty.  kernel stack for the stuck process looks like below.
 #0 [ffff88303d107b58] __schedule at ffffffff815c4b20
 #1 [ffff88303d107bd0] schedule at ffffffff815c513e
 #2 [ffff88303d107bf0] schedule_timeout at ffffffff815c7818
 #3 [ffff88303d107ca0] wait_woken at ffffffff81096bd2
 #4 [ffff88303d107ce0] n_tty_read at ffffffff8136fa23
 #5 [ffff88303d107dd0] tty_read at ffffffff81368013
 #6 [ffff88303d107e20] __vfs_read at ffffffff811a3704
 #7 [ffff88303d107ec0] vfs_read at ffffffff811a3a57
 #8 [ffff88303d107f00] sys_read at ffffffff811a4306
 #9 [ffff88303d107f50] entry_SYSCALL_64_fastpath at ffffffff815c86d7

There seems to be two problems causing this issue.

First, in drivers/tty/n_tty.c, __receive_buf() stores the data and
updates ldata->commit_head using smp_store_release() and then checks
the wait queue using waitqueue_active().  However, since there is no
memory barrier, __receive_buf() could return without calling
wake_up_interactive_poll(), and at the same time, n_tty_read() could
start to wait in wait_woken() as in the following chart.

        __receive_buf()                         n_tty_read()
------------------------------------------------------------------------
if (waitqueue_active(&tty->read_wait))
/* Memory operations issued after the
   RELEASE may be completed before the
   RELEASE operation has completed */
                                        add_wait_queue(&tty->read_wait, &wait);
                                        ...
                                        if (!input_available_p(tty, 0)) {
smp_store_release(&ldata->commit_head,
                  ldata->read_head);
                                        ...
                                        timeout = wait_woken(&wait,
                                          TASK_INTERRUPTIBLE, timeout);
------------------------------------------------------------------------

The second problem is that n_tty_read() also lacks a memory barrier
call and could also cause __receive_buf() to return without calling
wake_up_interactive_poll(), and n_tty_read() to wait in wait_woken()
as in the chart below.

        __receive_buf()                         n_tty_read()
------------------------------------------------------------------------
                                        spin_lock_irqsave(&q->lock, flags);
                                        /* from add_wait_queue() */
                                        ...
                                        if (!input_available_p(tty, 0)) {
                                        /* Memory operations issued after the
                                           RELEASE may be completed before the
                                           RELEASE operation has completed */
smp_store_release(&ldata->commit_head,
                  ldata->read_head);
if (waitqueue_active(&tty->read_wait))
                                        __add_wait_queue(q, wait);
                                        spin_unlock_irqrestore(&q->lock,flags);
                                        /* from add_wait_queue() */
                                        ...
                                        timeout = wait_woken(&wait,
                                          TASK_INTERRUPTIBLE, timeout);
------------------------------------------------------------------------

There are also other places in drivers/tty/n_tty.c which have similar
calls to waitqueue_active(), so instead of adding many memory barrier
calls, this patch simply removes the call to waitqueue_active(),
leaving just wake_up*() behind.

This fixes both problems because, even though the memory access before
or after the spinlocks in both wake_up*() and add_wait_queue() can
sneak into the critical section, it cannot go past it and the critical
section assures that they will be serialized (please see "INTER-CPU
ACQUIRING BARRIER EFFECTS" in Documentation/memory-barriers.txt for a
better explanation).  Moreover, the resulting code is much simpler.

Latency measurement using a ping-pong test over a pty doesn't show any
visible performance drop.

Signed-off-by: Kosuke Tatsukawa <tatsu@ab.jp.nec.com>
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
nkskjames pushed a commit to nkskjames/linux that referenced this pull request Jan 13, 2016
…ap_device_late_init

Kernel fails to boot 50% of times (form build to build) with
RT-patchset applied due to the following race - on late boot
stages deferred_probe_work_func->omap_hsmmc_probe races with omap_device_late_ini.

The same issue has been reported now on linux-next (4.3) by Keerthy [1]

late_initcall
 - deferred_probe_initcal() tries to re-probe all pending driver's probe.

- later on, some driver is probing in this case It's cpsw.c
  (but could be any other drivers)
  cpsw_init
  - platform_driver_register
    - really_probe
       - driver_bound
         - driver_deferred_probe_trigger
  and boot proceed.
  So, at this moment we have deferred_probe_work_func scheduled.

late_initcall_sync
  - omap_device_late_init
    - omap_device_idle

CPU1					CPU2
  - deferred_probe_work_func
    - really_probe
      - omap_hsmmc_probe
	- pm_runtime_get_sync
					late_initcall_sync
					- omap_device_late_init
						if (od->_driver_status != BUS_NOTIFY_BOUND_DRIVER) {
							if (od->_state == OMAP_DEVICE_STATE_ENABLED) {
								- omap_device_idle [ops - IP is disabled]
	- [fail]
	- pm_runtime_put_sync
          - omap_hsmmc_runtime_suspend [ooops!]

== log ==
 omap_hsmmc 480b4000.mmc: unable to get vmmc regulator -517
 davinci_mdio 48485000.mdio: davinci mdio revision 1.6
 davinci_mdio 48485000.mdio: detected phy mask fffffff3
 libphy: 48485000.mdio: probed
 davinci_mdio 48485000.mdio: phy[2]: device 48485000.mdio:02, driver unknown
 davinci_mdio 48485000.mdio: phy[3]: device 48485000.mdio:03, driver unknown
 omap_hsmmc 480b4000.mmc: unable to get vmmc regulator -517
 cpsw 48484000.ethernet: Detected MACID = b4:99:4c:c7:d2:48
 cpsw 48484000.ethernet: cpsw: Detected MACID = b4:99:4c:c7:d2:49
 hctosys: unable to open rtc device (rtc0)
 omap_hsmmc 480b4000.mmc: omap_device_late_idle: enabled but no driver.  Idling
 ldousb: disabling
 Unhandled fault: imprecise external abort (0x1406) at 0x00000000
 [00000000] *pgd=00000000
 Internal error: : 1406 [openbmc#1] PREEMPT SMP ARM
 Modules linked in:
 CPU: 1 PID: 58 Comm: kworker/u4:1 Not tainted 4.1.2-rt1-00467-g6da3c0a-dirty openbmc#5
 Hardware name: Generic DRA74X (Flattened Device Tree)
 Workqueue: deferwq deferred_probe_work_func
 task: ee6ddb00 ti: edd3c000 task.ti: edd3c000
 PC is at omap_hsmmc_runtime_suspend+0x1c/0x12c
 LR is at _od_runtime_suspend+0xc/0x24
 pc : [<c0471998>]    lr : [<c0029590>]    psr: a0000013
 sp : edd3dda0  ip : ee6ddb00  fp : c07be540
 r10: 00000000  r9 : c07be540  r8 : 00000008
 r7 : 00000000  r6 : ee646c10  r5 : ee646c10  r4 : edd79380
 r3 : fa0b4100  r2 : 00000000  r1 : 00000000  r0 : ee646c10
 Flags: NzCv  IRQs on  FIQs on  Mode SVC_32  ISA ARM  Segment kernel
 Control: 10c5387d  Table: 8000406a  DAC: 00000015
 Process kworker/u4:1 (pid: 58, stack limit = 0xedd3c218)
 Stack: (0xedd3dda0 to 0xedd3e000)
 dda0: ee646c70 ee646c10 c0029584 00000000 00000008 c0029590 ee646c70 ee646c10
 ddc0: c0029584 c03adfb8 ee646c10 00000004 0000000c c03adff0 ee646c10 00000004
 dde0: 0000000c c03ae4ec 00000000 edd3c000 ee646c10 00000004 ee646c70 00000004
 de00: fa0b4000 c03aec20 ee6ddb00 ee646c10 00000004 ee646c70 ee646c10 fffffdfb
 de20: edd79380 00000000 fa0b4000 c03aee90 fffffdfb edd79000 ee646c00 c0474290
 de40: 00000000 edda24c0 edd79380 edc81f00 00000000 00000200 00000001 c06dd488
 de60: edda3960 ee646c10 ee646c10 c0824cc4 fffffdfb c0880c94 00000002 edc92600
 de80: c0836378 c03a7f84 ee646c10 c0824cc4 00000000 c0880c80 c0880c94 c03a6568
 dea0: 00000000 ee646c10 c03a66ac ee4f8000 00000000 00000001 edc92600 c03a4b40
 dec0: ee404c94 edc83c4c ee646c10 ee646c10 ee646c44 c03a63c4 ee646c10 ee646c10
 dee0: c0814448 c03a5aa8 ee646c10 c0814220 edd3c000 c03a5ec0 c0814250 ee6be400
 df00: edd3c000 c004e5bc ee6ddb01 00000078 ee6ddb00 ee4f8000 ee6be418 edd3c000
 df20: ee4f8028 00000088 c0836045 ee4f8000 ee6be400 c004e928 ee4f8028 00000000
 df40: c004e8ec 00000000 ee6bf1c0 ee6be400 c004e8ec 00000000 00000000 00000000
 df60: 00000000 c0053450 2e56fa97 00000000 afdffbd7 ee6be400 00000000 00000000
 df80: edd3df80 edd3df80 00000000 00000000 edd3df90 edd3df90 edd3dfac ee6bf1c0
 dfa0: c0053384 00000000 00000000 c000f668 00000000 00000000 00000000 00000000
 dfc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
 dfe0: 00000000 00000000 00000000 00000000 00000013 00000000 f1fc9d7e febfbdff
 [<c0471998>] (omap_hsmmc_runtime_suspend) from [<c0029590>] (_od_runtime_suspend+0xc/0x24)
 [<c0029590>] (_od_runtime_suspend) from [<c03adfb8>] (__rpm_callback+0x24/0x3c)
 [<c03adfb8>] (__rpm_callback) from [<c03adff0>] (rpm_callback+0x20/0x80)
 [<c03adff0>] (rpm_callback) from [<c03ae4ec>] (rpm_suspend+0xe4/0x618)
 [<c03ae4ec>] (rpm_suspend) from [<c03aee90>] (__pm_runtime_idle+0x60/0x80)
 [<c03aee90>] (__pm_runtime_idle) from [<c0474290>] (omap_hsmmc_probe+0x6bc/0xa7c)
 [<c0474290>] (omap_hsmmc_probe) from [<c03a7f84>] (platform_drv_probe+0x44/0xa4)
 [<c03a7f84>] (platform_drv_probe) from [<c03a6568>] (driver_probe_device+0x170/0x2b4)
 [<c03a6568>] (driver_probe_device) from [<c03a4b40>] (bus_for_each_drv+0x64/0x98)
 [<c03a4b40>] (bus_for_each_drv) from [<c03a63c4>] (device_attach+0x70/0x88)
 [<c03a63c4>] (device_attach) from [<c03a5aa8>] (bus_probe_device+0x84/0xac)
 [<c03a5aa8>] (bus_probe_device) from [<c03a5ec0>] (deferred_probe_work_func+0x58/0x88)
 [<c03a5ec0>] (deferred_probe_work_func) from [<c004e5bc>] (process_one_work+0x134/0x464)
 [<c004e5bc>] (process_one_work) from [<c004e928>] (worker_thread+0x3c/0x4fc)
 [<c004e928>] (worker_thread) from [<c0053450>] (kthread+0xcc/0xe4)
 [<c0053450>] (kthread) from [<c000f668>] (ret_from_fork+0x14/0x2c)
 Code: e594302c e593202c e584205c e594302c (e5932128)
 ---[ end trace 0000000000000002 ]---

The issue happens because omap_device_late_init() do not take into
account that some drivers are present, but their probes were not
finished successfully and where deferred instead. This is the valid
case, and omap_device_late_init() should not idle such devices.

To fix this issue, the value of omap_device->_driver_status field
should be checked not only for BUS_NOTIFY_BOUND_DRIVER (driver is
present and has been bound to device successfully), but also checked
for BUS_NOTIFY_BIND_DRIVER (driver about to be bound) - which means
driver is present and there was try to bind it to device.

[1] http://www.spinics.net/lists/arm-kernel/msg441880.html
Cc: Tero Kristo <t-kristo@ti.com>
Cc: Keerthy <j-keerthy@ti.com>
Tested-by: Keerthy <j-keerthy@ti.com>
Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
nkskjames pushed a commit to nkskjames/linux that referenced this pull request Jan 13, 2016
The renesas-irqc interrupt controller is cascaded to the GIC. Hence when
propagating wake-up settings to its parent interrupt controller, the
following lockdep warning is printed:

    =============================================
    [ INFO: possible recursive locking detected ]
    4.2.0-ape6evm-10725-g50fcd7643c034198 torvalds#280 Not tainted
    ---------------------------------------------
    s2ram/1072 is trying to acquire lock:
    (&irq_desc_lock_class){-.-...}, at: [<c008d3fc>] __irq_get_desc_lock+0x58/0x98

    but task is already holding lock:
    (&irq_desc_lock_class){-.-...}, at: [<c008d3fc>] __irq_get_desc_lock+0x58/0x98

    other info that might help us debug this:
    Possible unsafe locking scenario:

	  CPU0
	  ----
     lock(&irq_desc_lock_class);
     lock(&irq_desc_lock_class);

    *** DEADLOCK ***

    May be due to missing lock nesting notation

    6 locks held by s2ram/1072:
    #0:  (sb_writers#7){.+.+.+}, at: [<c012eb14>] __sb_start_write+0xa0/0xa8
    openbmc#1:  (&of->mutex){+.+.+.}, at: [<c019396c>] kernfs_fop_write+0x4c/0x1bc
    openbmc#2:  (s_active#24){.+.+.+}, at: [<c0193974>] kernfs_fop_write+0x54/0x1bc
    openbmc#3:  (pm_mutex){+.+.+.}, at: [<c008213c>] pm_suspend+0x10c/0x510
    openbmc#4:  (&dev->mutex){......}, at: [<c02af3c4>] __device_suspend+0xdc/0x2cc
    openbmc#5:  (&irq_desc_lock_class){-.-...}, at: [<c008d3fc>] __irq_get_desc_lock+0x58/0x98

    stack backtrace:
    CPU: 0 PID: 1072 Comm: s2ram Not tainted 4.2.0-ape6evm-10725-g50fcd7643c034198 torvalds#280
    Hardware name: Generic R8A73A4 (Flattened Device Tree)
    [<c0018078>] (unwind_backtrace) from [<c00144f0>] (show_stack+0x10/0x14)
    [<c00144f0>] (show_stack) from [<c0451f14>] (dump_stack+0x88/0x98)
    [<c0451f14>] (dump_stack) from [<c007b29c>] (__lock_acquire+0x15cc/0x20e4)
    [<c007b29c>] (__lock_acquire) from [<c007c6e0>] (lock_acquire+0xac/0x12c)
    [<c007c6e0>] (lock_acquire) from [<c0457c00>] (_raw_spin_lock_irqsave+0x40/0x54)
    [<c0457c00>] (_raw_spin_lock_irqsave) from [<c008d3fc>] (__irq_get_desc_lock+0x58/0x98)
    [<c008d3fc>] (__irq_get_desc_lock) from [<c008ebbc>] (irq_set_irq_wake+0x20/0xf8)
    [<c008ebbc>] (irq_set_irq_wake) from [<c0260770>] (irqc_irq_set_wake+0x20/0x4c)
    [<c0260770>] (irqc_irq_set_wake) from [<c008ec28>] (irq_set_irq_wake+0x8c/0xf8)
    [<c008ec28>] (irq_set_irq_wake) from [<c02cb8c0>] (gpio_keys_suspend+0x74/0xc0)
    [<c02cb8c0>] (gpio_keys_suspend) from [<c02ae8cc>] (dpm_run_callback+0x54/0x124)

Avoid this false positive by using a separate lockdep class for IRQC
interrupts.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: Grygorii Strashko <grygorii.strashko@ti.com>
Cc: Magnus Damm <magnus.damm@gmail.com>
Cc: Jason Cooper <jason@lakedaemon.net>
Link: http://lkml.kernel.org/r/1441798974-25716-2-git-send-email-geert%2Brenesas@glider.be
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
nkskjames pushed a commit to nkskjames/linux that referenced this pull request Jan 13, 2016
The renesas-intc-irqpin interrupt controller is cascaded to the GIC.
Hence when propagating wake-up settings to its parent interrupt
controller, the following lockdep warning is printed:

    =============================================
    [ INFO: possible recursive locking detected ]
    4.2.0-armadillo-10725-g50fcd7643c034198 torvalds#781 Not tainted
    ---------------------------------------------
    s2ram/1179 is trying to acquire lock:
    (&irq_desc_lock_class){-.-...}, at: [<c005bb54>] __irq_get_desc_lock+0x78/0x94

    but task is already holding lock:
    (&irq_desc_lock_class){-.-...}, at: [<c005bb54>] __irq_get_desc_lock+0x78/0x94

    other info that might help us debug this:
    Possible unsafe locking scenario:

	  CPU0
	  ----
     lock(&irq_desc_lock_class);
     lock(&irq_desc_lock_class);

    *** DEADLOCK ***

    May be due to missing lock nesting notation

    7 locks held by s2ram/1179:
    #0:  (sb_writers#7){.+.+.+}, at: [<c00c9708>] __sb_start_write+0x64/0xb8
    openbmc#1:  (&of->mutex){+.+.+.}, at: [<c0125a00>] kernfs_fop_write+0x78/0x1a0
    openbmc#2:  (s_active#23){.+.+.+}, at: [<c0125a08>] kernfs_fop_write+0x80/0x1a0
    openbmc#3:  (autosleep_lock){+.+.+.}, at: [<c0058244>] pm_autosleep_lock+0x18/0x20
    openbmc#4:  (pm_mutex){+.+.+.}, at: [<c0057e50>] pm_suspend+0x54/0x248
    openbmc#5:  (&dev->mutex){......}, at: [<c0243a20>] __device_suspend+0xdc/0x240
    openbmc#6:  (&irq_desc_lock_class){-.-...}, at: [<c005bb54>] __irq_get_desc_lock+0x78/0x94

    stack backtrace:
    CPU: 0 PID: 1179 Comm: s2ram Not tainted 4.2.0-armadillo-10725-g50fcd7643c034198

    Hardware name: Generic R8A7740 (Flattened Device Tree)
    [<c00129f4>] (dump_backtrace) from [<c0012bec>] (show_stack+0x18/0x1c)
    [<c0012bd4>] (show_stack) from [<c03f5d94>] (dump_stack+0x20/0x28)
    [<c03f5d74>] (dump_stack) from [<c00514d4>] (__lock_acquire+0x67c/0x1b88)
    [<c0050e58>] (__lock_acquire) from [<c0052df8>] (lock_acquire+0x9c/0xbc)
    [<c0052d5c>] (lock_acquire) from [<c03fb068>] (_raw_spin_lock_irqsave+0x44/0x58)
    [<c03fb024>] (_raw_spin_lock_irqsave) from [<c005bb54>] (__irq_get_desc_lock+0x78/0x94
    [<c005badc>] (__irq_get_desc_lock) from [<c005c3d8>] (irq_set_irq_wake+0x28/0x100)
    [<c005c3b0>] (irq_set_irq_wake) from [<c01e50d0>] (intc_irqpin_irq_set_wake+0x24/0x4c)
    [<c01e50ac>] (intc_irqpin_irq_set_wake) from [<c005c17c>] (set_irq_wake_real+0x3c/0x50
    [<c005c140>] (set_irq_wake_real) from [<c005c414>] (irq_set_irq_wake+0x64/0x100)
    [<c005c3b0>] (irq_set_irq_wake) from [<c02a19b4>] (gpio_keys_suspend+0x60/0xa0)
    [<c02a1954>] (gpio_keys_suspend) from [<c023b750>] (platform_pm_suspend+0x3c/0x5c)

Avoid this false positive by using a separate lockdep class for INTC
External IRQ Pin interrupts.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: Grygorii Strashko <grygorii.strashko@ti.com>
Cc: Magnus Damm <magnus.damm@gmail.com>
Cc: Jason Cooper <jason@lakedaemon.net>
Link: http://lkml.kernel.org/r/1441798974-25716-3-git-send-email-geert%2Brenesas@glider.be
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
nkskjames pushed a commit to nkskjames/linux that referenced this pull request Jan 13, 2016
My colleague ran into a program stall on a x86_64 server, where
n_tty_read() was waiting for data even if there was data in the buffer
in the pty.  kernel stack for the stuck process looks like below.
 #0 [ffff88303d107b58] __schedule at ffffffff815c4b20
 openbmc#1 [ffff88303d107bd0] schedule at ffffffff815c513e
 openbmc#2 [ffff88303d107bf0] schedule_timeout at ffffffff815c7818
 openbmc#3 [ffff88303d107ca0] wait_woken at ffffffff81096bd2
 openbmc#4 [ffff88303d107ce0] n_tty_read at ffffffff8136fa23
 openbmc#5 [ffff88303d107dd0] tty_read at ffffffff81368013
 openbmc#6 [ffff88303d107e20] __vfs_read at ffffffff811a3704
 openbmc#7 [ffff88303d107ec0] vfs_read at ffffffff811a3a57
 openbmc#8 [ffff88303d107f00] sys_read at ffffffff811a4306
 openbmc#9 [ffff88303d107f50] entry_SYSCALL_64_fastpath at ffffffff815c86d7

There seems to be two problems causing this issue.

First, in drivers/tty/n_tty.c, __receive_buf() stores the data and
updates ldata->commit_head using smp_store_release() and then checks
the wait queue using waitqueue_active().  However, since there is no
memory barrier, __receive_buf() could return without calling
wake_up_interactive_poll(), and at the same time, n_tty_read() could
start to wait in wait_woken() as in the following chart.

        __receive_buf()                         n_tty_read()
------------------------------------------------------------------------
if (waitqueue_active(&tty->read_wait))
/* Memory operations issued after the
   RELEASE may be completed before the
   RELEASE operation has completed */
                                        add_wait_queue(&tty->read_wait, &wait);
                                        ...
                                        if (!input_available_p(tty, 0)) {
smp_store_release(&ldata->commit_head,
                  ldata->read_head);
                                        ...
                                        timeout = wait_woken(&wait,
                                          TASK_INTERRUPTIBLE, timeout);
------------------------------------------------------------------------

The second problem is that n_tty_read() also lacks a memory barrier
call and could also cause __receive_buf() to return without calling
wake_up_interactive_poll(), and n_tty_read() to wait in wait_woken()
as in the chart below.

        __receive_buf()                         n_tty_read()
------------------------------------------------------------------------
                                        spin_lock_irqsave(&q->lock, flags);
                                        /* from add_wait_queue() */
                                        ...
                                        if (!input_available_p(tty, 0)) {
                                        /* Memory operations issued after the
                                           RELEASE may be completed before the
                                           RELEASE operation has completed */
smp_store_release(&ldata->commit_head,
                  ldata->read_head);
if (waitqueue_active(&tty->read_wait))
                                        __add_wait_queue(q, wait);
                                        spin_unlock_irqrestore(&q->lock,flags);
                                        /* from add_wait_queue() */
                                        ...
                                        timeout = wait_woken(&wait,
                                          TASK_INTERRUPTIBLE, timeout);
------------------------------------------------------------------------

There are also other places in drivers/tty/n_tty.c which have similar
calls to waitqueue_active(), so instead of adding many memory barrier
calls, this patch simply removes the call to waitqueue_active(),
leaving just wake_up*() behind.

This fixes both problems because, even though the memory access before
or after the spinlocks in both wake_up*() and add_wait_queue() can
sneak into the critical section, it cannot go past it and the critical
section assures that they will be serialized (please see "INTER-CPU
ACQUIRING BARRIER EFFECTS" in Documentation/memory-barriers.txt for a
better explanation).  Moreover, the resulting code is much simpler.

Latency measurement using a ping-pong test over a pty doesn't show any
visible performance drop.

Signed-off-by: Kosuke Tatsukawa <tatsu@ab.jp.nec.com>
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
shenki pushed a commit that referenced this pull request Mar 21, 2016
When a43eec3 ("bpf: introduce bpf_perf_event_output() helper") added
PERF_COUNT_SW_BPF_OUTPUT we ended up with a new entry in the event_symbols_sw
array that wasn't initialized, thus set to NULL, fix print_symbol_events()
to check for that case so that we don't crash if this happens again.

  (gdb) bt
  #0  __match_glob (ignore_space=false, pat=<optimized out>, str=<optimized out>) at util/string.c:198
  #1  strglobmatch (str=<optimized out>, pat=pat@entry=0x7fffffffe61d "stall") at util/string.c:252
  #2  0x00000000004993a5 in print_symbol_events (type=1, syms=0x872880 <event_symbols_sw+160>, max=11, name_only=false, event_glob=0x7fffffffe61d "stall")
      at util/parse-events.c:1615
  #3  print_events (event_glob=event_glob@entry=0x7fffffffe61d "stall", name_only=false) at util/parse-events.c:1675
  #4  0x000000000042c79e in cmd_list (argc=1, argv=0x7fffffffe390, prefix=<optimized out>) at builtin-list.c:68
  #5  0x00000000004788a5 in run_builtin (p=p@entry=0x871758 <commands+120>, argc=argc@entry=2, argv=argv@entry=0x7fffffffe390) at perf.c:370
  #6  0x0000000000420ab0 in handle_internal_command (argv=0x7fffffffe390, argc=2) at perf.c:429
  #7  run_argv (argv=0x7fffffffe110, argcp=0x7fffffffe11c) at perf.c:473
  #8  main (argc=2, argv=0x7fffffffe390) at perf.c:588
  (gdb) p event_symbols_sw[PERF_COUNT_SW_BPF_OUTPUT]
  $4 = {symbol = 0x0, alias = 0x0}
  (gdb)

A patch to robustify perf to not segfault when the next counter gets added in
the kernel will follow this one.

Reported-by: Ingo Molnar <mingo@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-57wysblcjfrseb0zg5u7ek10@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
shenki pushed a commit that referenced this pull request May 5, 2016
…arm header

commit a6002ec upstream.

arm and arm64 use different config options to specify big endian. This
needs taking into account when including code/headers between the two
architectures.

A case in point is PAN, which uses the __instr_arm() macro to output
instructions. The macro comes from opcodes.h, which lives under arch/arm.
On a big-endian build the mismatched config options mean the instruction
isn't byte swapped correctly, resulting in undefined instruction exceptions
during boot:

| alternatives: patching kernel code
| kdevtmpfs[87]: undefined instruction: pc=ffffffc0004505b4
| kdevtmpfs[87]: undefined instruction: pc=ffffffc00076231c
| kdevtmpfs[87]: undefined instruction: pc=ffffffc00076231c
| kdevtmpfs[87]: undefined instruction: pc=ffffffc00076231c
| kdevtmpfs[87]: undefined instruction: pc=ffffffc00076231c
| kdevtmpfs[87]: undefined instruction: pc=ffffffc00076231c
| kdevtmpfs[87]: undefined instruction: pc=ffffffc00076231c
| kdevtmpfs[87]: undefined instruction: pc=ffffffc00076231c
| kdevtmpfs[87]: undefined instruction: pc=ffffffc00076231c
| kdevtmpfs[87]: undefined instruction: pc=ffffffc00076231c
| Internal error: Oops - undefined instruction: 0 [#1] SMP
| Modules linked in:
| CPU: 0 PID: 87 Comm: kdevtmpfs Not tainted 4.1.16+ #5
| Hardware name: Hisilicon PhosphorHi1382 EVB (DT)
| task: ffffffc336591700 ti: ffffffc3365a4000 task.ti: ffffffc3365a4000
| PC is at dump_instr+0x68/0x100
| LR is at do_undefinstr+0x1d4/0x2a4
| pc : [<ffffffc00076231c>] lr : [<ffffffc0000811d4>] pstate: 604001c5
| sp : ffffffc3365a6450

Reported-by: Hanjun Guo <guohanjun@huawei.com>
Tested-by: Xuefeng Wang <wxf.wang@hisilicon.com>
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
shenki pushed a commit that referenced this pull request Jun 8, 2016
commit c9eb13a upstream.

If the orphaned inode list contains inode #5, ext4_iget() returns a
bad inode (since the bootloader inode should never be referenced
directly).  Because of the bad inode, we end up processing the inode
repeatedly and this hangs the machine.

This can be reproduced via:

   mke2fs -t ext4 /tmp/foo.img 100
   debugfs -w -R "ssv last_orphan 5" /tmp/foo.img
   mount -o loop /tmp/foo.img /mnt

(But don't do this if you are using an unpatched kernel if you care
about the system staying functional.  :-)

This bug was found by the port of American Fuzzy Lop into the kernel
to find file system problems[1].  (Since it *only* happens if inode #5
shows up on the orphan list --- 3, 7, 8, etc. won't do it, it's not
surprising that AFL needed two hours before it found it.)

[1] http://events.linuxfoundation.org/sites/events/files/slides/AFL%20filesystem%20fuzzing%2C%20Vault%202016_0.pdf

Reported by: Vegard Nossum <vegard.nossum@oracle.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
amboar pushed a commit to amboar/linux that referenced this pull request Jul 12, 2016
The incorrect GPIO mask cause kernel warning, when AR9462 access GPIO11.
Also fix the mask for AR9565.

WARNING: CPU: 1 PID: 199 at ../drivers/net/wireless/ath/ath9k/hw.c:2778 ath9k_hw_gpio_get+0x1a9/0x1b0 [ath9k_hw]
CPU: 1 PID: 199 Comm: kworker/u16:9 Not tainted 4.7.0-rc1-next-20160530+ openbmc#5
Hardware name: Acer TravelMate P243/BA40_HC, BIOS V1.01 04/20/2012
Workqueue: events_power_efficient rfkill_poll
 0000000000000000 ffff88002cf73d28 ffffffff813b8ddc 0000000000000000
 0000000000000000 ffff88002cf73d68 ffffffff8107a331 00000ada00000086
 ffff880148d9c018 000000000000000b ffff880147e68720 0000000000000200
Call Trace:
 [<ffffffff813b8ddc>] dump_stack+0x63/0x87
 [<ffffffff8107a331>] __warn+0xd1/0xf0
 [<ffffffff8107a41d>] warn_slowpath_null+0x1d/0x20
 [<ffffffffc0775b19>] ath9k_hw_gpio_get+0x1a9/0x1b0 [ath9k_hw]
 [<ffffffffc047f3e4>] ath9k_rfkill_poll_state+0x34/0x60 [ath9k]
 [<ffffffffc06dbb53>] ieee80211_rfkill_poll+0x33/0x40 [mac80211]
 [<ffffffffc03ad65a>] cfg80211_rfkill_poll+0x2a/0xc0 [cfg80211]
 [<ffffffff817c5514>] rfkill_poll+0x24/0x50
 [<ffffffff81093183>] process_one_work+0x153/0x3f0
 [<ffffffff8109393b>] worker_thread+0x12b/0x4b0
 [<ffffffff81093810>] ? rescuer_thread+0x340/0x340
 [<ffffffff81099129>] kthread+0xc9/0xe0
 [<ffffffff817d8f1f>] ret_from_fork+0x1f/0x40
 [<ffffffff81099060>] ? kthread_park+0x60/0x60

Fixes: a01ab81 ("ath9k: define correct GPIO numbers and bits mask")
Reported-by: Sudip Mukherjee <sudip.mukherjee@codethink.co.uk>
Tested-by: Sudip Mukherjee <sudip.mukherjee@codethink.co.uk>
Signed-off-by: Miaoqing Pan <miaoqing@codeaurora.org>
Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>
shenki pushed a commit that referenced this pull request Jul 22, 2016
commit c9eb13a upstream.

If the orphaned inode list contains inode #5, ext4_iget() returns a
bad inode (since the bootloader inode should never be referenced
directly).  Because of the bad inode, we end up processing the inode
repeatedly and this hangs the machine.

This can be reproduced via:

   mke2fs -t ext4 /tmp/foo.img 100
   debugfs -w -R "ssv last_orphan 5" /tmp/foo.img
   mount -o loop /tmp/foo.img /mnt

(But don't do this if you are using an unpatched kernel if you care
about the system staying functional.  :-)

This bug was found by the port of American Fuzzy Lop into the kernel
to find file system problems[1].  (Since it *only* happens if inode #5
shows up on the orphan list --- 3, 7, 8, etc. won't do it, it's not
surprising that AFL needed two hours before it found it.)

[1] http://events.linuxfoundation.org/sites/events/files/slides/AFL%20filesystem%20fuzzing%2C%20Vault%202016_0.pdf

Reported by: Vegard Nossum <vegard.nossum@oracle.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
amboar pushed a commit to amboar/linux that referenced this pull request Aug 5, 2016
commit ec183d2 upstream.

Fixes segmentation fault using, for instance:

  (gdb) run record -I -e intel_pt/tsc=1,noretcomp=1/u /bin/ls
  Starting program: /home/acme/bin/perf record -I -e intel_pt/tsc=1,noretcomp=1/u /bin/ls
  Missing separate debuginfos, use: dnf debuginfo-install glibc-2.22-7.fc23.x86_64
  [Thread debugging using libthread_db enabled]
  Using host libthread_db library "/lib64/libthread_db.so.1".

 Program received signal SIGSEGV, Segmentation fault.
  0 x00000000004b9ea5 in tracepoint_error (e=0x0, err=13, sys=0x19b1370 "sched", name=0x19a5d00 "sched_switch") at util/parse-events.c:410
  (gdb) bt
  #0  0x00000000004b9ea5 in tracepoint_error (e=0x0, err=13, sys=0x19b1370 "sched", name=0x19a5d00 "sched_switch") at util/parse-events.c:410
  openbmc#1  0x00000000004b9fc5 in add_tracepoint (list=0x19a5d20, idx=0x7fffffffb8c0, sys_name=0x19b1370 "sched", evt_name=0x19a5d00 "sched_switch", err=0x0, head_config=0x0)
      at util/parse-events.c:433
  openbmc#2  0x00000000004ba334 in add_tracepoint_event (list=0x19a5d20, idx=0x7fffffffb8c0, sys_name=0x19b1370 "sched", evt_name=0x19a5d00 "sched_switch", err=0x0, head_config=0x0)
      at util/parse-events.c:498
  openbmc#3  0x00000000004bb699 in parse_events_add_tracepoint (list=0x19a5d20, idx=0x7fffffffb8c0, sys=0x19b1370 "sched", event=0x19a5d00 "sched_switch", err=0x0, head_config=0x0)
      at util/parse-events.c:936
  openbmc#4  0x00000000004f6eda in parse_events_parse (_data=0x7fffffffb8b0, scanner=0x19a49d0) at util/parse-events.y:391
  openbmc#5  0x00000000004bc8e5 in parse_events__scanner (str=0x663ff2 "sched:sched_switch", data=0x7fffffffb8b0, start_token=258) at util/parse-events.c:1361
  openbmc#6  0x00000000004bca57 in parse_events (evlist=0x19a5220, str=0x663ff2 "sched:sched_switch", err=0x0) at util/parse-events.c:1401
  openbmc#7  0x0000000000518d5f in perf_evlist__can_select_event (evlist=0x19a3b90, str=0x663ff2 "sched:sched_switch") at util/record.c:253
  openbmc#8  0x0000000000553c42 in intel_pt_track_switches (evlist=0x19a3b90) at arch/x86/util/intel-pt.c:364
  openbmc#9  0x00000000005549d1 in intel_pt_recording_options (itr=0x19a2c40, evlist=0x19a3b90, opts=0x8edf68 <record+232>) at arch/x86/util/intel-pt.c:664
  openbmc#10 0x000000000051e076 in auxtrace_record__options (itr=0x19a2c40, evlist=0x19a3b90, opts=0x8edf68 <record+232>) at util/auxtrace.c:539
  openbmc#11 0x0000000000433368 in cmd_record (argc=1, argv=0x7fffffffde60, prefix=0x0) at builtin-record.c:1264
  openbmc#12 0x000000000049bec2 in run_builtin (p=0x8fa2a8 <commands+168>, argc=5, argv=0x7fffffffde60) at perf.c:390
  openbmc#13 0x000000000049c12a in handle_internal_command (argc=5, argv=0x7fffffffde60) at perf.c:451
  openbmc#14 0x000000000049c278 in run_argv (argcp=0x7fffffffdcbc, argv=0x7fffffffdcb0) at perf.c:495
  openbmc#15 0x000000000049c60a in main (argc=5, argv=0x7fffffffde60) at perf.c:618
(gdb)

Intel PT attempts to find the sched:sched_switch tracepoint but that seg
faults if tracefs is not readable, because the error reporting structure
is null, as errors are not reported when automatically adding
tracepoints.  Fix by checking before using.

Committer note:

This doesn't take place in a kernel that supports
perf_event_attr.context_switch, that is the default way that will be
used for tracking context switches, only in older kernels, like 4.2, in
a machine with Intel PT (e.g. Broadwell) for non-priviledged users.

Further info from a similar patch by Wang:

The error is in tracepoint_error: it assumes the 'e' parameter is valid.

However, there are many situation a parse_event() can be called without
parse_events_error. See result of

  $ grep 'parse_events(.*NULL)' ./tools/perf/ -r'

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Tong Zhang <ztong@vt.edu>
Cc: Wang Nan <wangnan0@huawei.com>
Fixes: 1965817 ("perf tools: Enhance parsing events tracepoint error output")
Link: http://lkml.kernel.org/r/1453809921-24596-2-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
amboar pushed a commit to amboar/linux that referenced this pull request Aug 5, 2016
commit d144dfe upstream.

If we use USB ID pin as wakeup source, and there is a USB block
device on this USB OTG (ID) cable, the system will be deadlock
after system resume.

The root cause for this problem is: the workqueue ci_otg may try
to remove hcd before the driver resume has finished, and hcd will
disconnect the device on it, then, it will call device_release_driver,
and holds the device lock "dev->mutex", but it is never unlocked since
it waits workqueue writeback to run to flush the block information, but
the workqueue writeback is freezable, it is not thawed before driver
resume has finished.

When the driver (device: sd 0:0:0:0:) resume goes to dpm_complete, it
tries to get its device lock "dev->mutex", but it can't get it forever,
then the deadlock occurs. Below call stacks show the situation.

So, in order to fix this problem, we need to change workqueue ci_otg
as freezable, then the work item in this workqueue will be run after
driver's resume, this workqueue will not be blocked forever like above
case since the workqueue writeback has been thawed too.

Tested at: i.mx6qdl-sabresd and i.mx6sx-sdb.

[  555.178869] kworker/u2:13   D c07de74c     0   826      2 0x00000000
[  555.185310] Workqueue: ci_otg ci_otg_work
[  555.189353] Backtrace:
[  555.191849] [<c07de4fc>] (__schedule) from [<c07dec6c>] (schedule+0x48/0xa0)
[  555.198912]  r10:ee471ba0 r9:00000000 r8:00000000 r7:00000002 r6:ee470000 r5:ee471ba4
[  555.206867]  r4:ee470000
[  555.209453] [<c07dec24>] (schedule) from [<c07e2fc4>] (schedule_timeout+0x15c/0x1e0)
[  555.217212]  r4:7fffffff r3:edc2b000
[  555.220862] [<c07e2e68>] (schedule_timeout) from [<c07df6c8>] (wait_for_common+0x94/0x144)
[  555.229140]  r8:00000000 r7:00000002 r6:ee470000 r5:ee471ba4 r4:7fffffff
[  555.235980] [<c07df634>] (wait_for_common) from [<c07df790>] (wait_for_completion+0x18/0x1c)
[  555.244430]  r10:00000001 r9:c0b5563c r8:c0042e48 r7:ef086000 r6:eea4372c r5:ef131b00
[  555.252383]  r4:00000000
[  555.254970] [<c07df778>] (wait_for_completion) from [<c0043cb8>] (flush_work+0x19c/0x234)
[  555.263177] [<c0043b1c>] (flush_work) from [<c0043fac>] (flush_delayed_work+0x48/0x4c)
[  555.271106]  r8:ed5b5000 r7:c0b38a3c r6:eea439cc r5:eea4372c r4:eea4372c
[  555.277958] [<c0043f64>] (flush_delayed_work) from [<c00eae18>] (bdi_unregister+0x84/0xec)
[  555.286236]  r4:eea43520 r3:20000153
[  555.289885] [<c00ead94>] (bdi_unregister) from [<c02c2154>] (blk_cleanup_queue+0x180/0x29c)
[  555.298250]  r5:eea43808 r4:eea43400
[  555.301909] [<c02c1fd4>] (blk_cleanup_queue) from [<c0417914>] (__scsi_remove_device+0x48/0xb8)
[  555.310623]  r7:00000000 r6:20000153 r5:ededa950 r4:ededa800
[  555.316403] [<c04178cc>] (__scsi_remove_device) from [<c0415e90>] (scsi_forget_host+0x64/0x68)
[  555.325028]  r5:ededa800 r4:ed5b5000
[  555.328689] [<c0415e2c>] (scsi_forget_host) from [<c0409828>] (scsi_remove_host+0x78/0x104)
[  555.337054]  r5:ed5b5068 r4:ed5b5000
[  555.340709] [<c04097b0>] (scsi_remove_host) from [<c04cdfcc>] (usb_stor_disconnect+0x50/0xb4)
[  555.349247]  r6:ed5b56e4 r5:ed5b5818 r4:ed5b5690 r3:00000008
[  555.355025] [<c04cdf7c>] (usb_stor_disconnect) from [<c04b3bc8>] (usb_unbind_interface+0x78/0x25c)
[  555.363997]  r8:c13919b4 r7:edd3c000 r6:edd3c020 r5:ee551c68 r4:ee551c00 r3:c04cdf7c
[  555.371892] [<c04b3b50>] (usb_unbind_interface) from [<c03dc248>] (__device_release_driver+0x8c/0x118)
[  555.381213]  r10:00000001 r9:edd90c00 r8:c13919b4 r7:ee551c68 r6:c0b546e0 r5:c0b5563c
[  555.389167]  r4:edd3c020
[  555.391752] [<c03dc1bc>] (__device_release_driver) from [<c03dc2fc>] (device_release_driver+0x28/0x34)
[  555.401071]  r5:edd3c020 r4:edd3c054
[  555.404721] [<c03dc2d4>] (device_release_driver) from [<c03db304>] (bus_remove_device+0xe0/0x110)
[  555.413607]  r5:edd3c020 r4:ef17f04c
[  555.417253] [<c03db224>] (bus_remove_device) from [<c03d8128>] (device_del+0x114/0x21c)
[  555.425270]  r6:edd3c028 r5:edd3c020 r4:ee551c00 r3:00000000
[  555.431045] [<c03d8014>] (device_del) from [<c04b1560>] (usb_disable_device+0xa4/0x1e8)
[  555.439061]  r8:edd3c000 r7:eded8000 r6:00000000 r5:00000001 r4:ee551c00
[  555.445906] [<c04b14bc>] (usb_disable_device) from [<c04a8e54>] (usb_disconnect+0x74/0x224)
[  555.454271]  r9:edd90c00 r8:ee551000 r7:ee551c68 r6:ee551c9c r5:ee551c00 r4:00000001
[  555.462156] [<c04a8de0>] (usb_disconnect) from [<c04a8fb8>] (usb_disconnect+0x1d8/0x224)
[  555.470259]  r10:00000001 r9:edd90000 r8:ee471e2c r7:ee551468 r6:ee55149c r5:ee551400
[  555.478213]  r4:00000001
[  555.480797] [<c04a8de0>] (usb_disconnect) from [<c04ae5ec>] (usb_remove_hcd+0xa0/0x1ac)
[  555.488813]  r10:00000001 r9:ee471eb0 r8:00000000 r7:ef3d9500 r6:eded810c r5:eded80b0
[  555.496765]  r4:eded8000
[  555.499351] [<c04ae54c>] (usb_remove_hcd) from [<c04d4158>] (host_stop+0x28/0x64)
[  555.506847]  r6:eeb50010 r5:eded8000 r4:eeb51010
[  555.511563] [<c04d4130>] (host_stop) from [<c04d09b8>] (ci_otg_work+0xc4/0x124)
[  555.518885]  r6:00000001 r5:eeb50010 r4:eeb502a0 r3:c04d4130
[  555.524665] [<c04d08f4>] (ci_otg_work) from [<c00454f0>] (process_one_work+0x194/0x420)
[  555.532682]  r6:ef086000 r5:eeb502a0 r4:edc44480
[  555.537393] [<c004535c>] (process_one_work) from [<c00457b0>] (worker_thread+0x34/0x514)
[  555.545496]  r10:edc44480 r9:ef086000 r8:c0b1a100 r7:ef086034 r6:00000088 r5:edc44498
[  555.553450]  r4:ef086000
[  555.556032] [<c004577c>] (worker_thread) from [<c004bab4>] (kthread+0xdc/0xf8)
[  555.563268]  r10:00000000 r9:00000000 r8:00000000 r7:c004577c r6:edc44480 r5:eddc15c0
[  555.571221]  r4:00000000
[  555.573804] [<c004b9d8>] (kthread) from [<c000fef0>] (ret_from_fork+0x14/0x24)
[  555.581040]  r7:00000000 r6:00000000 r5:c004b9d8 r4:eddc15c0

[  553.429383] sh              D c07de74c     0   694    691 0x00000000
[  553.435801] Backtrace:
[  553.438295] [<c07de4fc>] (__schedule) from [<c07dec6c>] (schedule+0x48/0xa0)
[  553.445358]  r10:edd3c054 r9:edd3c078 r8:edddbd50 r7:edcbbc00 r6:c1377c34 r5:60000153
[  553.453313]  r4:eddda000
[  553.455896] [<c07dec24>] (schedule) from [<c07deff8>] (schedule_preempt_disabled+0x10/0x14)
[  553.464261]  r4:edd3c058 r3:0000000a
[  553.467910] [<c07defe8>] (schedule_preempt_disabled) from [<c07e0bbc>] (mutex_lock_nested+0x1a0/0x3e8)
[  553.477254] [<c07e0a1c>] (mutex_lock_nested) from [<c03e927c>] (dpm_complete+0xc0/0x1b0)
[  553.485358]  r10:00561408 r9:edd3c054 r8:c0b4863c r7:edddbd90 r6:c0b485d8 r5:edd3c020
[  553.493313]  r4:edd3c0d0
[  553.495896] [<c03e91bc>] (dpm_complete) from [<c03e9388>] (dpm_resume_end+0x1c/0x20)
[  553.503652]  r9:00000000 r8:c0b1a9d0 r7:c1334ec0 r6:c1334edc r5:00000003 r4:00000010
[  553.511544] [<c03e936c>] (dpm_resume_end) from [<c0079894>] (suspend_devices_and_enter+0x158/0x504)
[  553.520604]  r4:00000000 r3:c1334efc
[  553.524250] [<c007973c>] (suspend_devices_and_enter) from [<c0079e74>] (pm_suspend+0x234/0x2cc)
[  553.532961]  r10:00561408 r9:ed6b7300 r8:00000004 r7:c1334eec r6:00000000 r5:c1334ee8
[  553.540914]  r4:00000003
[  553.543493] [<c0079c40>] (pm_suspend) from [<c0078a6c>] (state_store+0x6c/0xc0)

[  555.703684] 7 locks held by kworker/u2:13/826:
[  555.708140]  #0:  ("%s""ci_otg"){++++.+}, at: [<c0045484>] process_one_work+0x128/0x420
[  555.716277]  openbmc#1:  ((&ci->work)){+.+.+.}, at: [<c0045484>] process_one_work+0x128/0x420
[  555.724317]  openbmc#2:  (usb_bus_list_lock){+.+.+.}, at: [<c04ae5e4>] usb_remove_hcd+0x98/0x1ac
[  555.732626]  openbmc#3:  (&dev->mutex){......}, at: [<c04a8e28>] usb_disconnect+0x48/0x224
[  555.740403]  openbmc#4:  (&dev->mutex){......}, at: [<c04a8e28>] usb_disconnect+0x48/0x224
[  555.748179]  openbmc#5:  (&dev->mutex){......}, at: [<c03dc2f4>] device_release_driver+0x20/0x34
[  555.756487]  openbmc#6:  (&shost->scan_mutex){+.+.+.}, at: [<c04097d0>] scsi_remove_host+0x20/0x104

Cc: Jun Li <jun.li@nxp.com>
Signed-off-by: Peter Chen <peter.chen@nxp.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
amboar pushed a commit to amboar/linux that referenced this pull request Sep 28, 2016
drm_connector_register_all requires a few too many locks because our
connector_list locking is busted. Add another FIXME+hack to work
around this. This should address the below lockdep splat:

======================================================
[ INFO: possible circular locking dependency detected ]
4.7.0-rc5+ torvalds#524 Tainted: G           O
-------------------------------------------------------
kworker/u8:0/6 is trying to acquire lock:
 (&dev->mode_config.mutex){+.+.+.}, at: [<ffffffff815afde0>] drm_modeset_lock_all+0x40/0x120

but task is already holding lock:
 ((fb_notifier_list).rwsem){++++.+}, at: [<ffffffff810ac195>] __blocking_notifier_call_chain+0x35/0x70

which lock already depends on the new lock.

the existing dependency chain (in reverse order) is:

-> openbmc#1 ((fb_notifier_list).rwsem){++++.+}:
       [<ffffffff810df611>] lock_acquire+0xb1/0x200
       [<ffffffff819a55b4>] down_write+0x44/0x80
       [<ffffffff810abf91>] blocking_notifier_chain_register+0x21/0xb0
       [<ffffffff814c7448>] fb_register_client+0x18/0x20
       [<ffffffff814c6c86>] backlight_device_register+0x136/0x260
       [<ffffffffa0127eb2>] intel_backlight_device_register+0xa2/0x160 [i915]
       [<ffffffffa00f46be>] intel_connector_register+0xe/0x10 [i915]
       [<ffffffffa0112bfb>] intel_dp_connector_register+0x1b/0x80 [i915]
       [<ffffffff8159dfea>] drm_connector_register+0x4a/0x80
       [<ffffffff8159fe44>] drm_connector_register_all+0x64/0xf0
       [<ffffffff815a2a64>] drm_modeset_register_all+0x174/0x1c0
       [<ffffffff81599b72>] drm_dev_register+0xc2/0xd0
       [<ffffffffa00621d7>] i915_driver_load+0x1547/0x2200 [i915]
       [<ffffffffa006d80f>] i915_pci_probe+0x4f/0x70 [i915]
       [<ffffffff814a2135>] local_pci_probe+0x45/0xa0
       [<ffffffff814a349b>] pci_device_probe+0xdb/0x130
       [<ffffffff815c07e3>] driver_probe_device+0x223/0x440
       [<ffffffff815c0ad5>] __driver_attach+0xd5/0x100
       [<ffffffff815be386>] bus_for_each_dev+0x66/0xa0
       [<ffffffff815c002e>] driver_attach+0x1e/0x20
       [<ffffffff815bf9be>] bus_add_driver+0x1ee/0x280
       [<ffffffff815c1810>] driver_register+0x60/0xe0
       [<ffffffff814a1a10>] __pci_register_driver+0x60/0x70
       [<ffffffffa01a905b>] i915_init+0x5b/0x62 [i915]
       [<ffffffff8100042d>] do_one_initcall+0x3d/0x150
       [<ffffffff811a935b>] do_init_module+0x5f/0x1d9
       [<ffffffff81124416>] load_module+0x20e6/0x27e0
       [<ffffffff81124d63>] SYSC_finit_module+0xc3/0xf0
       [<ffffffff81124dae>] SyS_finit_module+0xe/0x10
       [<ffffffff819a83a9>] entry_SYSCALL_64_fastpath+0x1c/0xac

-> #0 (&dev->mode_config.mutex){+.+.+.}:
       [<ffffffff810df0ac>] __lock_acquire+0x10fc/0x1260
       [<ffffffff810df611>] lock_acquire+0xb1/0x200
       [<ffffffff819a3097>] mutex_lock_nested+0x67/0x3c0
       [<ffffffff815afde0>] drm_modeset_lock_all+0x40/0x120
       [<ffffffff8158f79b>] drm_fb_helper_restore_fbdev_mode_unlocked+0x2b/0x80
       [<ffffffff8158f81d>] drm_fb_helper_set_par+0x2d/0x50
       [<ffffffffa0105f7a>] intel_fbdev_set_par+0x1a/0x60 [i915]
       [<ffffffff814c13c6>] fbcon_init+0x586/0x610
       [<ffffffff8154d16a>] visual_init+0xca/0x130
       [<ffffffff8154e611>] do_bind_con_driver+0x1c1/0x3a0
       [<ffffffff8154eaf6>] do_take_over_console+0x116/0x180
       [<ffffffff814bd3a7>] do_fbcon_takeover+0x57/0xb0
       [<ffffffff814c1e48>] fbcon_event_notify+0x658/0x750
       [<ffffffff810abcae>] notifier_call_chain+0x3e/0xb0
       [<ffffffff810ac1ad>] __blocking_notifier_call_chain+0x4d/0x70
       [<ffffffff810ac1e6>] blocking_notifier_call_chain+0x16/0x20
       [<ffffffff814c748b>] fb_notifier_call_chain+0x1b/0x20
       [<ffffffff814c86b1>] register_framebuffer+0x251/0x330
       [<ffffffff8158fa9f>] drm_fb_helper_initial_config+0x25f/0x3f0
       [<ffffffffa0106b48>] intel_fbdev_initial_config+0x18/0x30 [i915]
       [<ffffffff810adfd8>] async_run_entry_fn+0x48/0x150
       [<ffffffff810a3947>] process_one_work+0x1e7/0x750
       [<ffffffff810a3efb>] worker_thread+0x4b/0x4f0
       [<ffffffff810aad4f>] kthread+0xef/0x110
       [<ffffffff819a85ef>] ret_from_fork+0x1f/0x40

other info that might help us debug this:

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock((fb_notifier_list).rwsem);
                               lock(&dev->mode_config.mutex);
                               lock((fb_notifier_list).rwsem);
  lock(&dev->mode_config.mutex);

 *** DEADLOCK ***

6 locks held by kworker/u8:0/6:
 #0:  ("events_unbound"){.+.+.+}, at: [<ffffffff810a38c9>] process_one_work+0x169/0x750
 openbmc#1:  ((&entry->work)){+.+.+.}, at: [<ffffffff810a38c9>] process_one_work+0x169/0x750
 openbmc#2:  (registration_lock){+.+.+.}, at: [<ffffffff814c8487>] register_framebuffer+0x27/0x330
 openbmc#3:  (console_lock){+.+.+.}, at: [<ffffffff814c86ce>] register_framebuffer+0x26e/0x330
 openbmc#4:  (&fb_info->lock){+.+.+.}, at: [<ffffffff814c78dd>] lock_fb_info+0x1d/0x40
 openbmc#5:  ((fb_notifier_list).rwsem){++++.+}, at: [<ffffffff810ac195>] __blocking_notifier_call_chain+0x35/0x70

stack backtrace:
CPU: 2 PID: 6 Comm: kworker/u8:0 Tainted: G           O    4.7.0-rc5+ torvalds#524
Hardware name: Intel Corp. Broxton P/NOTEBOOK, BIOS APLKRVPA.X64.0138.B33.1606250842 06/25/2016
Workqueue: events_unbound async_run_entry_fn
 0000000000000000 ffff8800758577f0 ffffffff814507a5 ffffffff828b9900
 ffffffff828b9900 ffff880075857830 ffffffff810dc6fa ffff880075857880
 ffff88007584d688 0000000000000005 0000000000000006 ffff88007584d6b0
Call Trace:
 [<ffffffff814507a5>] dump_stack+0x67/0x92
 [<ffffffff810dc6fa>] print_circular_bug+0x1aa/0x200
 [<ffffffff810df0ac>] __lock_acquire+0x10fc/0x1260
 [<ffffffff810df611>] lock_acquire+0xb1/0x200
 [<ffffffff815afde0>] ? drm_modeset_lock_all+0x40/0x120
 [<ffffffff815afde0>] ? drm_modeset_lock_all+0x40/0x120
 [<ffffffff819a3097>] mutex_lock_nested+0x67/0x3c0
 [<ffffffff815afde0>] ? drm_modeset_lock_all+0x40/0x120
 [<ffffffff810fa85f>] ? rcu_read_lock_sched_held+0x7f/0x90
 [<ffffffff81208218>] ? kmem_cache_alloc_trace+0x248/0x2b0
 [<ffffffff815afdc5>] ? drm_modeset_lock_all+0x25/0x120
 [<ffffffff815afde0>] drm_modeset_lock_all+0x40/0x120
 [<ffffffff8158f79b>] drm_fb_helper_restore_fbdev_mode_unlocked+0x2b/0x80
 [<ffffffff8158f81d>] drm_fb_helper_set_par+0x2d/0x50
 [<ffffffffa0105f7a>] intel_fbdev_set_par+0x1a/0x60 [i915]
 [<ffffffff814c13c6>] fbcon_init+0x586/0x610
 [<ffffffff8154d16a>] visual_init+0xca/0x130
 [<ffffffff8154e611>] do_bind_con_driver+0x1c1/0x3a0
 [<ffffffff8154eaf6>] do_take_over_console+0x116/0x180
 [<ffffffff814bd3a7>] do_fbcon_takeover+0x57/0xb0
 [<ffffffff814c1e48>] fbcon_event_notify+0x658/0x750
 [<ffffffff810abcae>] notifier_call_chain+0x3e/0xb0
 [<ffffffff810ac1ad>] __blocking_notifier_call_chain+0x4d/0x70
 [<ffffffff810ac1e6>] blocking_notifier_call_chain+0x16/0x20
 [<ffffffff814c748b>] fb_notifier_call_chain+0x1b/0x20
 [<ffffffff814c86b1>] register_framebuffer+0x251/0x330
 [<ffffffff815b7e8d>] ? vga_switcheroo_client_fb_set+0x5d/0x70
 [<ffffffff8158fa9f>] drm_fb_helper_initial_config+0x25f/0x3f0
 [<ffffffffa0106b48>] intel_fbdev_initial_config+0x18/0x30 [i915]
 [<ffffffff810adfd8>] async_run_entry_fn+0x48/0x150
 [<ffffffff810a3947>] process_one_work+0x1e7/0x750
 [<ffffffff810a38c9>] ? process_one_work+0x169/0x750
 [<ffffffff810a3efb>] worker_thread+0x4b/0x4f0
 [<ffffffff810a3eb0>] ? process_one_work+0x750/0x750
 [<ffffffff810aad4f>] kthread+0xef/0x110
 [<ffffffff819a85ef>] ret_from_fork+0x1f/0x40
 [<ffffffff810aac60>] ? kthread_stop+0x2e0/0x2e0

v2: Rebase onto the right branch (hand-editing patches ftw) and add more
reporters.

Reported-by: Imre Deak <imre.deak@intel.com>
Cc: Imre Deak <imre.deak@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Acked-by: Chris Wilson <chris@chris-wilson.co.uk>
Reported-by: Jiri Kosina <jikos@kernel.org>
Cc: Jiri Kosina <jikos@kernel.org>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
amboar pushed a commit to amboar/linux that referenced this pull request Sep 28, 2016
If kexec_apply_relocations fails, kexec_load_purgatory frees pi->sechdrs
and pi->purgatory_buf.  This is redundant, because in case of error
kimage_file_prepare_segments calls kimage_file_post_load_cleanup, which
will also free those buffers.

This causes two warnings like the following, one for pi->sechdrs and the
other for pi->purgatory_buf:

  kexec-bzImage64: Loading purgatory failed
  ------------[ cut here ]------------
  WARNING: CPU: 1 PID: 2119 at mm/vmalloc.c:1490 __vunmap+0xc1/0xd0
  Trying to vfree() nonexistent vm area (ffffc90000e91000)
  Modules linked in:
  CPU: 1 PID: 2119 Comm: kexec Not tainted 4.8.0-rc3+ openbmc#5
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
  Call Trace:
    dump_stack+0x4d/0x65
    __warn+0xcb/0xf0
    warn_slowpath_fmt+0x4f/0x60
    ? find_vmap_area+0x19/0x70
    ? kimage_file_post_load_cleanup+0x47/0xb0
    __vunmap+0xc1/0xd0
    vfree+0x2e/0x70
    kimage_file_post_load_cleanup+0x5e/0xb0
    SyS_kexec_file_load+0x448/0x680
    ? putname+0x54/0x60
    ? do_sys_open+0x190/0x1f0
    entry_SYSCALL_64_fastpath+0x13/0x8f
  ---[ end trace 158bb74f5950ca2b ]---

Fix by setting pi->sechdrs an pi->purgatory_buf to NULL, since vfree
won't try to free a NULL pointer.

Link: http://lkml.kernel.org/r/1472083546-23683-1-git-send-email-bauerman@linux.vnet.ibm.com
Signed-off-by: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Acked-by: Baoquan He <bhe@redhat.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
shenki pushed a commit that referenced this pull request Oct 6, 2016
commit 070c43e upstream.

If kexec_apply_relocations fails, kexec_load_purgatory frees pi->sechdrs
and pi->purgatory_buf.  This is redundant, because in case of error
kimage_file_prepare_segments calls kimage_file_post_load_cleanup, which
will also free those buffers.

This causes two warnings like the following, one for pi->sechdrs and the
other for pi->purgatory_buf:

  kexec-bzImage64: Loading purgatory failed
  ------------[ cut here ]------------
  WARNING: CPU: 1 PID: 2119 at mm/vmalloc.c:1490 __vunmap+0xc1/0xd0
  Trying to vfree() nonexistent vm area (ffffc90000e91000)
  Modules linked in:
  CPU: 1 PID: 2119 Comm: kexec Not tainted 4.8.0-rc3+ #5
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
  Call Trace:
    dump_stack+0x4d/0x65
    __warn+0xcb/0xf0
    warn_slowpath_fmt+0x4f/0x60
    ? find_vmap_area+0x19/0x70
    ? kimage_file_post_load_cleanup+0x47/0xb0
    __vunmap+0xc1/0xd0
    vfree+0x2e/0x70
    kimage_file_post_load_cleanup+0x5e/0xb0
    SyS_kexec_file_load+0x448/0x680
    ? putname+0x54/0x60
    ? do_sys_open+0x190/0x1f0
    entry_SYSCALL_64_fastpath+0x13/0x8f
  ---[ end trace 158bb74f5950ca2b ]---

Fix by setting pi->sechdrs an pi->purgatory_buf to NULL, since vfree
won't try to free a NULL pointer.

Link: http://lkml.kernel.org/r/1472083546-23683-1-git-send-email-bauerman@linux.vnet.ibm.com
Signed-off-by: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Acked-by: Baoquan He <bhe@redhat.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Dave Young <dyoung@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
shenki pushed a commit that referenced this pull request Oct 21, 2016
commit 070c43e upstream.

If kexec_apply_relocations fails, kexec_load_purgatory frees pi->sechdrs
and pi->purgatory_buf.  This is redundant, because in case of error
kimage_file_prepare_segments calls kimage_file_post_load_cleanup, which
will also free those buffers.

This causes two warnings like the following, one for pi->sechdrs and the
other for pi->purgatory_buf:

  kexec-bzImage64: Loading purgatory failed
  ------------[ cut here ]------------
  WARNING: CPU: 1 PID: 2119 at mm/vmalloc.c:1490 __vunmap+0xc1/0xd0
  Trying to vfree() nonexistent vm area (ffffc90000e91000)
  Modules linked in:
  CPU: 1 PID: 2119 Comm: kexec Not tainted 4.8.0-rc3+ #5
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
  Call Trace:
    dump_stack+0x4d/0x65
    __warn+0xcb/0xf0
    warn_slowpath_fmt+0x4f/0x60
    ? find_vmap_area+0x19/0x70
    ? kimage_file_post_load_cleanup+0x47/0xb0
    __vunmap+0xc1/0xd0
    vfree+0x2e/0x70
    kimage_file_post_load_cleanup+0x5e/0xb0
    SyS_kexec_file_load+0x448/0x680
    ? putname+0x54/0x60
    ? do_sys_open+0x190/0x1f0
    entry_SYSCALL_64_fastpath+0x13/0x8f
  ---[ end trace 158bb74f5950ca2b ]---

Fix by setting pi->sechdrs an pi->purgatory_buf to NULL, since vfree
won't try to free a NULL pointer.

Link: http://lkml.kernel.org/r/1472083546-23683-1-git-send-email-bauerman@linux.vnet.ibm.com
Signed-off-by: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Acked-by: Baoquan He <bhe@redhat.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Dave Young <dyoung@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
shenki pushed a commit that referenced this pull request Oct 24, 2016
commit 420902c upstream.

If we hold the superblock lock while calling reiserfs_quota_on_mount(), we can
deadlock our own worker - mount blocks kworker/3:2, sleeps forever more.

crash> ps|grep UN
    715      2   3  ffff880220734d30  UN   0.0       0      0  [kworker/3:2]
   9369   9341   2  ffff88021ffb7560  UN   1.3  493404 123184  Xorg
   9665   9664   3  ffff880225b92ab0  UN   0.0   47368    812  udisks-daemon
  10635  10403   3  ffff880222f22c70  UN   0.0   14904    936  mount
crash> bt ffff880220734d30
PID: 715    TASK: ffff880220734d30  CPU: 3   COMMAND: "kworker/3:2"
 #0 [ffff8802244c3c20] schedule at ffffffff8144584b
 #1 [ffff8802244c3cc8] __rt_mutex_slowlock at ffffffff814472b3
 #2 [ffff8802244c3d28] rt_mutex_slowlock at ffffffff814473f5
 #3 [ffff8802244c3dc8] reiserfs_write_lock at ffffffffa05f28fd [reiserfs]
 #4 [ffff8802244c3de8] flush_async_commits at ffffffffa05ec91d [reiserfs]
 #5 [ffff8802244c3e08] process_one_work at ffffffff81073726
 #6 [ffff8802244c3e68] worker_thread at ffffffff81073eba
 #7 [ffff8802244c3ec8] kthread at ffffffff810782e0
 #8 [ffff8802244c3f48] kernel_thread_helper at ffffffff81450064
crash> rd ffff8802244c3cc8 10
ffff8802244c3cc8:  ffffffff814472b3 ffff880222f23250   .rD.....P2."....
ffff8802244c3cd8:  0000000000000000 0000000000000286   ................
ffff8802244c3ce8:  ffff8802244c3d30 ffff880220734d80   0=L$.....Ms ....
ffff8802244c3cf8:  ffff880222e8f628 0000000000000000   (.."............
ffff8802244c3d08:  0000000000000000 0000000000000002   ................
crash> struct rt_mutex ffff880222e8f628
struct rt_mutex {
  wait_lock = {
    raw_lock = {
      slock = 65537
    }
  },
  wait_list = {
    node_list = {
      next = 0xffff8802244c3d48,
      prev = 0xffff8802244c3d48
    }
  },
  owner = 0xffff880222f22c71,
  save_state = 0
}
crash> bt 0xffff880222f22c70
PID: 10635  TASK: ffff880222f22c70  CPU: 3   COMMAND: "mount"
 #0 [ffff8802216a9868] schedule at ffffffff8144584b
 #1 [ffff8802216a9910] schedule_timeout at ffffffff81446865
 #2 [ffff8802216a99a0] wait_for_common at ffffffff81445f74
 #3 [ffff8802216a9a30] flush_work at ffffffff810712d3
 #4 [ffff8802216a9ab0] schedule_on_each_cpu at ffffffff81074463
 #5 [ffff8802216a9ae0] invalidate_bdev at ffffffff81178aba
 #6 [ffff8802216a9af0] vfs_load_quota_inode at ffffffff811a3632
 #7 [ffff8802216a9b50] dquot_quota_on_mount at ffffffff811a375c
 #8 [ffff8802216a9b80] finish_unfinished at ffffffffa05dd8b0 [reiserfs]
 #9 [ffff8802216a9cc0] reiserfs_fill_super at ffffffffa05de825 [reiserfs]
    RIP: 00007f7b9303997a  RSP: 00007ffff443c7a8  RFLAGS: 00010202
    RAX: 00000000000000a5  RBX: ffffffff8144ef12  RCX: 00007f7b932e9ee0
    RDX: 00007f7b93d9a400  RSI: 00007f7b93d9a3e0  RDI: 00007f7b93d9a3c0
    RBP: 00007f7b93d9a2c0   R8: 00007f7b93d9a550   R9: 0000000000000001
    R10: ffffffffc0ed040e  R11: 0000000000000202  R12: 000000000000040e
    R13: 0000000000000000  R14: 00000000c0ed040e  R15: 00007ffff443ca20
    ORIG_RAX: 00000000000000a5  CS: 0033  SS: 002b

Signed-off-by: Mike Galbraith <efault@gmx.de>
Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
Acked-by: Mike Galbraith <mgalbraith@suse.de>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
shenki pushed a commit that referenced this pull request Nov 21, 2016
commit 420902c upstream.

If we hold the superblock lock while calling reiserfs_quota_on_mount(), we can
deadlock our own worker - mount blocks kworker/3:2, sleeps forever more.

crash> ps|grep UN
    715      2   3  ffff880220734d30  UN   0.0       0      0  [kworker/3:2]
   9369   9341   2  ffff88021ffb7560  UN   1.3  493404 123184  Xorg
   9665   9664   3  ffff880225b92ab0  UN   0.0   47368    812  udisks-daemon
  10635  10403   3  ffff880222f22c70  UN   0.0   14904    936  mount
crash> bt ffff880220734d30
PID: 715    TASK: ffff880220734d30  CPU: 3   COMMAND: "kworker/3:2"
 #0 [ffff8802244c3c20] schedule at ffffffff8144584b
 #1 [ffff8802244c3cc8] __rt_mutex_slowlock at ffffffff814472b3
 #2 [ffff8802244c3d28] rt_mutex_slowlock at ffffffff814473f5
 #3 [ffff8802244c3dc8] reiserfs_write_lock at ffffffffa05f28fd [reiserfs]
 #4 [ffff8802244c3de8] flush_async_commits at ffffffffa05ec91d [reiserfs]
 #5 [ffff8802244c3e08] process_one_work at ffffffff81073726
 #6 [ffff8802244c3e68] worker_thread at ffffffff81073eba
 #7 [ffff8802244c3ec8] kthread at ffffffff810782e0
 #8 [ffff8802244c3f48] kernel_thread_helper at ffffffff81450064
crash> rd ffff8802244c3cc8 10
ffff8802244c3cc8:  ffffffff814472b3 ffff880222f23250   .rD.....P2."....
ffff8802244c3cd8:  0000000000000000 0000000000000286   ................
ffff8802244c3ce8:  ffff8802244c3d30 ffff880220734d80   0=L$.....Ms ....
ffff8802244c3cf8:  ffff880222e8f628 0000000000000000   (.."............
ffff8802244c3d08:  0000000000000000 0000000000000002   ................
crash> struct rt_mutex ffff880222e8f628
struct rt_mutex {
  wait_lock = {
    raw_lock = {
      slock = 65537
    }
  },
  wait_list = {
    node_list = {
      next = 0xffff8802244c3d48,
      prev = 0xffff8802244c3d48
    }
  },
  owner = 0xffff880222f22c71,
  save_state = 0
}
crash> bt 0xffff880222f22c70
PID: 10635  TASK: ffff880222f22c70  CPU: 3   COMMAND: "mount"
 #0 [ffff8802216a9868] schedule at ffffffff8144584b
 #1 [ffff8802216a9910] schedule_timeout at ffffffff81446865
 #2 [ffff8802216a99a0] wait_for_common at ffffffff81445f74
 #3 [ffff8802216a9a30] flush_work at ffffffff810712d3
 #4 [ffff8802216a9ab0] schedule_on_each_cpu at ffffffff81074463
 #5 [ffff8802216a9ae0] invalidate_bdev at ffffffff81178aba
 #6 [ffff8802216a9af0] vfs_load_quota_inode at ffffffff811a3632
 #7 [ffff8802216a9b50] dquot_quota_on_mount at ffffffff811a375c
 #8 [ffff8802216a9b80] finish_unfinished at ffffffffa05dd8b0 [reiserfs]
 #9 [ffff8802216a9cc0] reiserfs_fill_super at ffffffffa05de825 [reiserfs]
    RIP: 00007f7b9303997a  RSP: 00007ffff443c7a8  RFLAGS: 00010202
    RAX: 00000000000000a5  RBX: ffffffff8144ef12  RCX: 00007f7b932e9ee0
    RDX: 00007f7b93d9a400  RSI: 00007f7b93d9a3e0  RDI: 00007f7b93d9a3c0
    RBP: 00007f7b93d9a2c0   R8: 00007f7b93d9a550   R9: 0000000000000001
    R10: ffffffffc0ed040e  R11: 0000000000000202  R12: 000000000000040e
    R13: 0000000000000000  R14: 00000000c0ed040e  R15: 00007ffff443ca20
    ORIG_RAX: 00000000000000a5  CS: 0033  SS: 002b

Signed-off-by: Mike Galbraith <efault@gmx.de>
Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
Acked-by: Mike Galbraith <mgalbraith@suse.de>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
amboar pushed a commit to amboar/linux that referenced this pull request Dec 23, 2016
Tushar Dave says:

====================
sparc: Enable sun4v hypervisor PCI IOMMU v2 APIs and ATU

ATU (Address Translation Unit) is a new IOMMU in SPARC supported with
sun4v hypervisor PCI IOMMU v2 APIs.

Current SPARC IOMMU supports only 32bit address ranges and one TSB
per PCIe root complex that has a 2GB per root complex DVMA space
limit. The limit has become a scalability bottleneck nowadays that
a typical 10G/40G NIC can consume 500MB DVMA space per instance.
When DVMA resource is exhausted, devices will not be usable
since the driver can't allocate DVMA.

For example, we recently experienced legacy IOMMU limitation while
using i40e driver in system with large number of CPUs (e.g. 128).
Four ports of i40e, each request 128 QP (Queue Pairs). Each queue has
512 (default) descriptors. So considering only RX queues (because RX
premap DMA buffers), i40e takes 4*128*512 number of DMA entries in
IOMMU table. Legacy IOMMU can have at max (2G/8K)- 1 entries available
in table. So bringing up four instance of i40e alone saturate existing
IOMMU resource.

ATU removes bottleneck by allowing guest os to create IOTSB of size
32G (or more) with 64bit address ranges available in ATU HW. 32G is
more than enough DVMA space to be shared by all PCIe devices under
root complex contrast to 2G space provided by legacy IOMMU.

ATU allows PCIe devices to use 64bit DMA addressing. Devices
which choose to use 32bit DMA mask will continue to work with the
existing legacy IOMMU.

The patch set is tested on sun4v (T1000, T2000, T3, T4, T5, T7, S7)
and sun4u SPARC.

Thanks.
-Tushar

v2->v3:
- Patch openbmc#5 addresses comment by Joe Perches.
 -- use %s, __func__ instead of embedding the function name.

v1->v2:
- Patch openbmc#2 addresses comments by Dave M.
 -- use page allocator to allocate IOTSB.
 -- use true/false with boolean variables.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
amboar pushed a commit to amboar/linux that referenced this pull request Apr 7, 2017
We cannot do printk() from tk_debug_account_sleep_time(), because
tk_debug_account_sleep_time() is called under tk_core seq lock.
The reason why printk() is unsafe there is that console_sem may
invoke scheduler (up()->wake_up_process()->activate_task()), which,
in turn, can return back to timekeeping code, for instance, via
get_time()->ktime_get(), deadlocking the system on tk_core seq lock.

[   48.950592] ======================================================
[   48.950622] [ INFO: possible circular locking dependency detected ]
[   48.950622] 4.10.0-rc7-next-20170213+ openbmc#101 Not tainted
[   48.950622] -------------------------------------------------------
[   48.950622] kworker/0:0/3 is trying to acquire lock:
[   48.950653]  (tk_core){----..}, at: [<c01cc624>] retrigger_next_event+0x4c/0x90
[   48.950683]
               but task is already holding lock:
[   48.950683]  (hrtimer_bases.lock){-.-...}, at: [<c01cc610>] retrigger_next_event+0x38/0x90
[   48.950714]
               which lock already depends on the new lock.

[   48.950714]
               the existing dependency chain (in reverse order) is:
[   48.950714]
               -> openbmc#5 (hrtimer_bases.lock){-.-...}:
[   48.950744]        _raw_spin_lock_irqsave+0x50/0x64
[   48.950775]        lock_hrtimer_base+0x28/0x58
[   48.950775]        hrtimer_start_range_ns+0x20/0x5c8
[   48.950775]        __enqueue_rt_entity+0x320/0x360
[   48.950805]        enqueue_rt_entity+0x2c/0x44
[   48.950805]        enqueue_task_rt+0x24/0x94
[   48.950836]        ttwu_do_activate+0x54/0xc0
[   48.950836]        try_to_wake_up+0x248/0x5c8
[   48.950836]        __setup_irq+0x420/0x5f0
[   48.950836]        request_threaded_irq+0xdc/0x184
[   48.950866]        devm_request_threaded_irq+0x58/0xa4
[   48.950866]        omap_i2c_probe+0x530/0x6a0
[   48.950897]        platform_drv_probe+0x50/0xb0
[   48.950897]        driver_probe_device+0x1f8/0x2cc
[   48.950897]        __driver_attach+0xc0/0xc4
[   48.950927]        bus_for_each_dev+0x6c/0xa0
[   48.950927]        bus_add_driver+0x100/0x210
[   48.950927]        driver_register+0x78/0xf4
[   48.950958]        do_one_initcall+0x3c/0x16c
[   48.950958]        kernel_init_freeable+0x20c/0x2d8
[   48.950958]        kernel_init+0x8/0x110
[   48.950988]        ret_from_fork+0x14/0x24
[   48.950988]
               -> openbmc#4 (&rt_b->rt_runtime_lock){-.-...}:
[   48.951019]        _raw_spin_lock+0x40/0x50
[   48.951019]        rq_offline_rt+0x9c/0x2bc
[   48.951019]        set_rq_offline.part.2+0x2c/0x58
[   48.951049]        rq_attach_root+0x134/0x144
[   48.951049]        cpu_attach_domain+0x18c/0x6f4
[   48.951049]        build_sched_domains+0xba4/0xd80
[   48.951080]        sched_init_smp+0x68/0x10c
[   48.951080]        kernel_init_freeable+0x160/0x2d8
[   48.951080]        kernel_init+0x8/0x110
[   48.951080]        ret_from_fork+0x14/0x24
[   48.951110]
               -> openbmc#3 (&rq->lock){-.-.-.}:
[   48.951110]        _raw_spin_lock+0x40/0x50
[   48.951141]        task_fork_fair+0x30/0x124
[   48.951141]        sched_fork+0x194/0x2e0
[   48.951141]        copy_process.part.5+0x448/0x1a20
[   48.951171]        _do_fork+0x98/0x7e8
[   48.951171]        kernel_thread+0x2c/0x34
[   48.951171]        rest_init+0x1c/0x18c
[   48.951202]        start_kernel+0x35c/0x3d4
[   48.951202]        0x8000807c
[   48.951202]
               -> openbmc#2 (&p->pi_lock){-.-.-.}:
[   48.951232]        _raw_spin_lock_irqsave+0x50/0x64
[   48.951232]        try_to_wake_up+0x30/0x5c8
[   48.951232]        up+0x4c/0x60
[   48.951263]        __up_console_sem+0x2c/0x58
[   48.951263]        console_unlock+0x3b4/0x650
[   48.951263]        vprintk_emit+0x270/0x474
[   48.951293]        vprintk_default+0x20/0x28
[   48.951293]        printk+0x20/0x30
[   48.951324]        kauditd_hold_skb+0x94/0xb8
[   48.951324]        kauditd_thread+0x1a4/0x56c
[   48.951324]        kthread+0x104/0x148
[   48.951354]        ret_from_fork+0x14/0x24
[   48.951354]
               -> openbmc#1 ((console_sem).lock){-.....}:
[   48.951385]        _raw_spin_lock_irqsave+0x50/0x64
[   48.951385]        down_trylock+0xc/0x2c
[   48.951385]        __down_trylock_console_sem+0x24/0x80
[   48.951385]        console_trylock+0x10/0x8c
[   48.951416]        vprintk_emit+0x264/0x474
[   48.951416]        vprintk_default+0x20/0x28
[   48.951416]        printk+0x20/0x30
[   48.951446]        tk_debug_account_sleep_time+0x5c/0x70
[   48.951446]        __timekeeping_inject_sleeptime.constprop.3+0x170/0x1a0
[   48.951446]        timekeeping_resume+0x218/0x23c
[   48.951477]        syscore_resume+0x94/0x42c
[   48.951477]        suspend_enter+0x554/0x9b4
[   48.951477]        suspend_devices_and_enter+0xd8/0x4b4
[   48.951507]        enter_state+0x934/0xbd4
[   48.951507]        pm_suspend+0x14/0x70
[   48.951507]        state_store+0x68/0xc8
[   48.951538]        kernfs_fop_write+0xf4/0x1f8
[   48.951538]        __vfs_write+0x1c/0x114
[   48.951538]        vfs_write+0xa0/0x168
[   48.951568]        SyS_write+0x3c/0x90
[   48.951568]        __sys_trace_return+0x0/0x10
[   48.951568]
               -> #0 (tk_core){----..}:
[   48.951599]        lock_acquire+0xe0/0x294
[   48.951599]        ktime_get_update_offsets_now+0x5c/0x1d4
[   48.951629]        retrigger_next_event+0x4c/0x90
[   48.951629]        on_each_cpu+0x40/0x7c
[   48.951629]        clock_was_set_work+0x14/0x20
[   48.951660]        process_one_work+0x2b4/0x808
[   48.951660]        worker_thread+0x3c/0x550
[   48.951660]        kthread+0x104/0x148
[   48.951690]        ret_from_fork+0x14/0x24
[   48.951690]
               other info that might help us debug this:

[   48.951690] Chain exists of:
                 tk_core --> &rt_b->rt_runtime_lock --> hrtimer_bases.lock

[   48.951721]  Possible unsafe locking scenario:

[   48.951721]        CPU0                    CPU1
[   48.951721]        ----                    ----
[   48.951721]   lock(hrtimer_bases.lock);
[   48.951751]                                lock(&rt_b->rt_runtime_lock);
[   48.951751]                                lock(hrtimer_bases.lock);
[   48.951751]   lock(tk_core);
[   48.951782]
                *** DEADLOCK ***

[   48.951782] 3 locks held by kworker/0:0/3:
[   48.951782]  #0:  ("events"){.+.+.+}, at: [<c0156590>] process_one_work+0x1f8/0x808
[   48.951812]  openbmc#1:  (hrtimer_work){+.+...}, at: [<c0156590>] process_one_work+0x1f8/0x808
[   48.951843]  openbmc#2:  (hrtimer_bases.lock){-.-...}, at: [<c01cc610>] retrigger_next_event+0x38/0x90
[   48.951843]   stack backtrace:
[   48.951873] CPU: 0 PID: 3 Comm: kworker/0:0 Not tainted 4.10.0-rc7-next-20170213+
[   48.951904] Workqueue: events clock_was_set_work
[   48.951904] [<c0110208>] (unwind_backtrace) from [<c010c224>] (show_stack+0x10/0x14)
[   48.951934] [<c010c224>] (show_stack) from [<c04ca6c0>] (dump_stack+0xac/0xe0)
[   48.951934] [<c04ca6c0>] (dump_stack) from [<c019b5cc>] (print_circular_bug+0x1d0/0x308)
[   48.951965] [<c019b5cc>] (print_circular_bug) from [<c019d2a8>] (validate_chain+0xf50/0x1324)
[   48.951965] [<c019d2a8>] (validate_chain) from [<c019ec18>] (__lock_acquire+0x468/0x7e8)
[   48.951995] [<c019ec18>] (__lock_acquire) from [<c019f634>] (lock_acquire+0xe0/0x294)
[   48.951995] [<c019f634>] (lock_acquire) from [<c01d0ea0>] (ktime_get_update_offsets_now+0x5c/0x1d4)
[   48.952026] [<c01d0ea0>] (ktime_get_update_offsets_now) from [<c01cc624>] (retrigger_next_event+0x4c/0x90)
[   48.952026] [<c01cc624>] (retrigger_next_event) from [<c01e4e24>] (on_each_cpu+0x40/0x7c)
[   48.952056] [<c01e4e24>] (on_each_cpu) from [<c01cafc4>] (clock_was_set_work+0x14/0x20)
[   48.952056] [<c01cafc4>] (clock_was_set_work) from [<c015664c>] (process_one_work+0x2b4/0x808)
[   48.952087] [<c015664c>] (process_one_work) from [<c0157774>] (worker_thread+0x3c/0x550)
[   48.952087] [<c0157774>] (worker_thread) from [<c015d644>] (kthread+0x104/0x148)
[   48.952087] [<c015d644>] (kthread) from [<c0107830>] (ret_from_fork+0x14/0x24)

Replace printk() with printk_deferred(), which does not call into
the scheduler.

Fixes: 0bf43f1 ("timekeeping: Prints the amounts of time spent during suspend")
Reported-and-tested-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: "Rafael J . Wysocki" <rjw@rjwysocki.net>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: John Stultz <john.stultz@linaro.org>
Cc: "[4.9+]" <stable@vger.kernel.org>
Link: http://lkml.kernel.org/r/20170215044332.30449-1-sergey.senozhatsky@gmail.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
amboar pushed a commit to amboar/linux that referenced this pull request Jun 22, 2017
'perf annotate' is dropping the cr* fields from branch instructions.

Fix it by adding support to display branch instructions having
multiple operands.

Power Arch objdump of int_sqrt:

 20.36 | c0000000004d2694:   subf   r10,r10,r3
       | c0000000004d2698: v bgt    cr6,c0000000004d26a0 <int_sqrt+0x40>
  1.82 | c0000000004d269c:   mr     r3,r10
 29.18 | c0000000004d26a0:   mr     r10,r8
       | c0000000004d26a4: v bgt    cr7,c0000000004d26ac <int_sqrt+0x4c>
       | c0000000004d26a8:   mr     r10,r7

Power Arch Before Patch:

 20.36 |       subf   r10,r10,r3
       |     v bgt    40
  1.82 |       mr     r3,r10
 29.18 | 40:   mr     r10,r8
       |     v bgt    4c
       |       mr     r10,r7

Power Arch After patch:

 20.36 |       subf   r10,r10,r3
       |     v bgt    cr6,40
  1.82 |       mr     r3,r10
 29.18 | 40:   mr     r10,r8
       |     v bgt    cr7,4c
       |       mr     r10,r7

Also support AArch64 conditional branch instructions, which can
have up to three operands:

Aarch64 Non-simplified (raw objdump) view:

       │ffff0000083cd11c: ↑ cbz    w0, ffff0000083cd100 <security_fil▒
...
  4.44 │ffff000│083cd134: ↓ tbnz   w0, openbmc#26, ffff0000083cd190 <securit▒
...
  1.37 │ffff000│083cd144: ↓ tbnz   w22, openbmc#5, ffff0000083cd1a4 <securit▒
       │ffff000│083cd148:   mov    w19, #0x20000                   //▒
  1.02 │ffff000│083cd14c: ↓ tbz    w22, openbmc#2, ffff0000083cd1ac <securit▒
...
  0.68 │ffff000└──3cd16c: ↑ cbnz   w0, ffff0000083cd120 <security_fil▒

Aarch64 Simplified, before this patch:

       │    ↑ cbz    40
...
  4.44 │   │↓ tbnz   w0, openbmc#26, ffff0000083cd190 <security_file_permiss▒
...
  1.37 │   │↓ tbnz   w22, openbmc#5, ffff0000083cd1a4 <security_file_permiss▒
       │   │  mov    w19, #0x20000                   // #131072
  1.02 │   │↓ tbz    w22, openbmc#2, ffff0000083cd1ac <security_file_permiss▒
...
  0.68 │   └──cbnz   60

the cbz operand is missing, and the tbz doesn't get simplified processing
at all because the parsing function failed to match an address.

Aarch64 Simplified, After this patch applied:

       │    ↑ cbz    w0, 40
...
  4.44 │   │↓ tbnz   w0, openbmc#26, d0
...
  1.37 │   │↓ tbnz   w22, openbmc#5, e4
       │   │  mov    w19, #0x20000                   // #131072
  1.02 │   │↓ tbz    w22, openbmc#2, ec
...
  0.68 │   └──cbnz   w0, 60

Originally-by: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
Tested-by: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
Reported-by: Anton Blanchard <anton@samba.org>
Reported-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Kim Phillips <kim.phillips@arm.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Taeung Song <treeze.taeung@gmail.com>
Link: http://lkml.kernel.org/r/20170601092959.f60d98912e8a1b66fd1e4c0e@arm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
amboar pushed a commit that referenced this pull request Mar 14, 2024
commit 817349b upstream.

Upstream commit bac1ec5 ("usb: xhci: Set quirk for
XHCI_SG_TRB_CACHE_SIZE_QUIRK") introduced a new quirk in XHCI
which fixes XHC timeout, which was seen on synopsys XHCs while
using SG buffers. But the support for this quirk isn't present
in the DWC3 layer.

We will encounter this XHCI timeout/hung issue if we run iperf
loopback tests using RTL8156 ethernet adaptor on DWC3 targets
with scatter-gather enabled. This gets resolved after enabling
the XHCI_SG_TRB_CACHE_SIZE_QUIRK. This patch enables it using
the xhci device property since its needed for DWC3 controller.

In Synopsys DWC3 databook,
Table 9-3: xHCI Debug Capability Limitations
Chained TRBs greater than TRB cache size: The debug capability
driver must not create a multi-TRB TD that describes smaller
than a 1K packet that spreads across 8 or more TRBs on either
the IN TR or the OUT TR.

Cc: stable@vger.kernel.org #5.11
Signed-off-by: Prashanth K <quic_prashk@quicinc.com>
Acked-by: Thinh Nguyen <Thinh.Nguyen@synopsys.com>
Link: https://lore.kernel.org/r/20240116055816.1169821-2-quic_prashk@quicinc.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
amboar pushed a commit that referenced this pull request Mar 14, 2024
[ Upstream commit d3ea125 ]

If CONFIG_HARDENED_USERCOPY is enabled, copying completion record from
event log cache to user triggers a kernel bug.

[ 1987.159822] usercopy: Kernel memory exposure attempt detected from SLUB object 'dsa0' (offset 74, size 31)!
[ 1987.170845] ------------[ cut here ]------------
[ 1987.176086] kernel BUG at mm/usercopy.c:102!
[ 1987.180946] invalid opcode: 0000 [#1] PREEMPT SMP NOPTI
[ 1987.186866] CPU: 17 PID: 528 Comm: kworker/17:1 Not tainted 6.8.0-rc2+ #5
[ 1987.194537] Hardware name: Intel Corporation AvenueCity/AvenueCity, BIOS BHSDCRB1.86B.2492.D03.2307181620 07/18/2023
[ 1987.206405] Workqueue: wq0.0 idxd_evl_fault_work [idxd]
[ 1987.212338] RIP: 0010:usercopy_abort+0x72/0x90
[ 1987.217381] Code: 58 65 9c 50 48 c7 c2 17 85 61 9c 57 48 c7 c7 98 fd 6b 9c 48 0f 44 d6 48 c7 c6 b3 08 62 9c 4c 89 d1 49 0f 44 f3 e8 1e 2e d5 ff <0f> 0b 49 c7 c1 9e 42 61 9c 4c 89 cf 4d 89 c8 eb a9 66 66 2e 0f 1f
[ 1987.238505] RSP: 0018:ff62f5cf20607d60 EFLAGS: 00010246
[ 1987.244423] RAX: 000000000000005f RBX: 000000000000001f RCX: 0000000000000000
[ 1987.252480] RDX: 0000000000000000 RSI: ffffffff9c61429e RDI: 00000000ffffffff
[ 1987.260538] RBP: ff62f5cf20607d78 R08: ff2a6a89ef3fffe8 R09: 00000000fffeffff
[ 1987.268595] R10: ff2a6a89eed00000 R11: 0000000000000003 R12: ff2a66934849c89a
[ 1987.276652] R13: 0000000000000001 R14: ff2a66934849c8b9 R15: ff2a66934849c899
[ 1987.284710] FS:  0000000000000000(0000) GS:ff2a66b22fe40000(0000) knlGS:0000000000000000
[ 1987.293850] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 1987.300355] CR2: 00007fe291a37000 CR3: 000000010fbd4005 CR4: 0000000000f71ef0
[ 1987.308413] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 1987.316470] DR3: 0000000000000000 DR6: 00000000fffe07f0 DR7: 0000000000000400
[ 1987.324527] PKRU: 55555554
[ 1987.327622] Call Trace:
[ 1987.330424]  <TASK>
[ 1987.332826]  ? show_regs+0x6e/0x80
[ 1987.336703]  ? die+0x3c/0xa0
[ 1987.339988]  ? do_trap+0xd4/0xf0
[ 1987.343662]  ? do_error_trap+0x75/0xa0
[ 1987.347922]  ? usercopy_abort+0x72/0x90
[ 1987.352277]  ? exc_invalid_op+0x57/0x80
[ 1987.356634]  ? usercopy_abort+0x72/0x90
[ 1987.360988]  ? asm_exc_invalid_op+0x1f/0x30
[ 1987.365734]  ? usercopy_abort+0x72/0x90
[ 1987.370088]  __check_heap_object+0xb7/0xd0
[ 1987.374739]  __check_object_size+0x175/0x2d0
[ 1987.379588]  idxd_copy_cr+0xa9/0x130 [idxd]
[ 1987.384341]  idxd_evl_fault_work+0x127/0x390 [idxd]
[ 1987.389878]  process_one_work+0x13e/0x300
[ 1987.394435]  ? __pfx_worker_thread+0x10/0x10
[ 1987.399284]  worker_thread+0x2f7/0x420
[ 1987.403544]  ? _raw_spin_unlock_irqrestore+0x2b/0x50
[ 1987.409171]  ? __pfx_worker_thread+0x10/0x10
[ 1987.414019]  kthread+0x107/0x140
[ 1987.417693]  ? __pfx_kthread+0x10/0x10
[ 1987.421954]  ret_from_fork+0x3d/0x60
[ 1987.426019]  ? __pfx_kthread+0x10/0x10
[ 1987.430281]  ret_from_fork_asm+0x1b/0x30
[ 1987.434744]  </TASK>

The issue arises because event log cache is created using
kmem_cache_create() which is not suitable for user copy.

Fix the issue by creating event log cache with
kmem_cache_create_usercopy(), ensuring safe user copy.

Fixes: c2f156b ("dmaengine: idxd: create kmem cache for event log fault items")
Reported-by: Tony Zhu <tony.zhu@intel.com>
Tested-by: Tony Zhu <tony.zhu@intel.com>
Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Reviewed-by: Lijun Pan <lijun.pan@intel.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/20240209191412.1050270-1-fenghua.yu@intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
amboar pushed a commit to amboar/linux that referenced this pull request Mar 25, 2024
…pty list

If all peers are removed via wg_peer_remove_all(), rather than setting
peer_list to empty, the peer is added to a temporary list with a head on
the stack of wg_peer_remove_all(). If a netlink dump is resumed and the
cursored peer is one that has been removed via wg_peer_remove_all(), it
will iterate from that peer and then attempt to dump freed peers.

Fix this by instead checking peer->is_dead, which was explictly created
for this purpose. Also move up the device_update_lock lockdep assertion,
since reading is_dead relies on that.

It can be reproduced by a small script like:

    echo "Setting config..."
    ip link add dev wg0 type wireguard
    wg setconf wg0 /big-config
    (
            while true; do
                    echo "Showing config..."
                    wg showconf wg0 > /dev/null
            done
    ) &
    sleep 4
    wg setconf wg0 <(printf "[Peer]\nPublicKey=$(wg genkey)\n")

Resulting in:

    BUG: KASAN: slab-use-after-free in __lock_acquire+0x182a/0x1b20
    Read of size 8 at addr ffff88811956ec70 by task wg/59
    CPU: 2 PID: 59 Comm: wg Not tainted 6.8.0-rc2-debug+ openbmc#5
    Call Trace:
     <TASK>
     dump_stack_lvl+0x47/0x70
     print_address_description.constprop.0+0x2c/0x380
     print_report+0xab/0x250
     kasan_report+0xba/0xf0
     __lock_acquire+0x182a/0x1b20
     lock_acquire+0x191/0x4b0
     down_read+0x80/0x440
     get_peer+0x140/0xcb0
     wg_get_device_dump+0x471/0x1130

Cc: stable@vger.kernel.org
Fixes: e7096c1 ("net: WireGuard secure network tunnel")
Reported-by: Lillian Berry <lillian@star-ark.net>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
amboar pushed a commit that referenced this pull request Apr 4, 2024
…pty list

[ Upstream commit 55b6c73 ]

If all peers are removed via wg_peer_remove_all(), rather than setting
peer_list to empty, the peer is added to a temporary list with a head on
the stack of wg_peer_remove_all(). If a netlink dump is resumed and the
cursored peer is one that has been removed via wg_peer_remove_all(), it
will iterate from that peer and then attempt to dump freed peers.

Fix this by instead checking peer->is_dead, which was explictly created
for this purpose. Also move up the device_update_lock lockdep assertion,
since reading is_dead relies on that.

It can be reproduced by a small script like:

    echo "Setting config..."
    ip link add dev wg0 type wireguard
    wg setconf wg0 /big-config
    (
            while true; do
                    echo "Showing config..."
                    wg showconf wg0 > /dev/null
            done
    ) &
    sleep 4
    wg setconf wg0 <(printf "[Peer]\nPublicKey=$(wg genkey)\n")

Resulting in:

    BUG: KASAN: slab-use-after-free in __lock_acquire+0x182a/0x1b20
    Read of size 8 at addr ffff88811956ec70 by task wg/59
    CPU: 2 PID: 59 Comm: wg Not tainted 6.8.0-rc2-debug+ #5
    Call Trace:
     <TASK>
     dump_stack_lvl+0x47/0x70
     print_address_description.constprop.0+0x2c/0x380
     print_report+0xab/0x250
     kasan_report+0xba/0xf0
     __lock_acquire+0x182a/0x1b20
     lock_acquire+0x191/0x4b0
     down_read+0x80/0x440
     get_peer+0x140/0xcb0
     wg_get_device_dump+0x471/0x1130

Cc: stable@vger.kernel.org
Fixes: e7096c1 ("net: WireGuard secure network tunnel")
Reported-by: Lillian Berry <lillian@star-ark.net>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
amboar pushed a commit that referenced this pull request Apr 4, 2024
commit 4be9075 upstream.

The driver creates /sys/kernel/debug/dri/0/mob_ttm even when the
corresponding ttm_resource_manager is not allocated.
This leads to a crash when trying to read from this file.

Add a check to create mob_ttm, system_mob_ttm, and gmr_ttm debug file
only when the corresponding ttm_resource_manager is allocated.

crash> bt
PID: 3133409  TASK: ffff8fe4834a5000  CPU: 3    COMMAND: "grep"
 #0 [ffffb954506b3b20] machine_kexec at ffffffffb2a6bec3
 #1 [ffffb954506b3b78] __crash_kexec at ffffffffb2bb598a
 #2 [ffffb954506b3c38] crash_kexec at ffffffffb2bb68c1
 #3 [ffffb954506b3c50] oops_end at ffffffffb2a2a9b1
 #4 [ffffb954506b3c70] no_context at ffffffffb2a7e913
 #5 [ffffb954506b3cc8] __bad_area_nosemaphore at ffffffffb2a7ec8c
 #6 [ffffb954506b3d10] do_page_fault at ffffffffb2a7f887
 #7 [ffffb954506b3d40] page_fault at ffffffffb360116e
    [exception RIP: ttm_resource_manager_debug+0x11]
    RIP: ffffffffc04afd11  RSP: ffffb954506b3df0  RFLAGS: 00010246
    RAX: ffff8fe41a6d1200  RBX: 0000000000000000  RCX: 0000000000000940
    RDX: 0000000000000000  RSI: ffffffffc04b4338  RDI: 0000000000000000
    RBP: ffffb954506b3e08   R8: ffff8fee3ffad000   R9: 0000000000000000
    R10: ffff8fe41a76a000  R11: 0000000000000001  R12: 00000000ffffffff
    R13: 0000000000000001  R14: ffff8fe5bb6f3900  R15: ffff8fe41a6d1200
    ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0018
 #8 [ffffb954506b3e00] ttm_resource_manager_show at ffffffffc04afde7 [ttm]
 #9 [ffffb954506b3e30] seq_read at ffffffffb2d8f9f3
    RIP: 00007f4c4eda8985  RSP: 00007ffdbba9e9f8  RFLAGS: 00000246
    RAX: ffffffffffffffda  RBX: 000000000037e000  RCX: 00007f4c4eda8985
    RDX: 000000000037e000  RSI: 00007f4c41573000  RDI: 0000000000000003
    RBP: 000000000037e000   R8: 0000000000000000   R9: 000000000037fe30
    R10: 0000000000000000  R11: 0000000000000246  R12: 00007f4c41573000
    R13: 0000000000000003  R14: 00007f4c41572010  R15: 0000000000000003
    ORIG_RAX: 0000000000000000  CS: 0033  SS: 002b

Signed-off-by: Jocelyn Falempe <jfalempe@redhat.com>
Fixes: af4a25b ("drm/vmwgfx: Add debugfs entries for various ttm resource managers")
Cc: <stable@vger.kernel.org>
Reviewed-by: Zack Rusin <zack.rusin@broadcom.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240312093551.196609-1-jfalempe@redhat.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
amboar pushed a commit that referenced this pull request Apr 15, 2024
[ Upstream commit 0bef512 ]

Based on a syzbot report, it appears many virtual
drivers do not yet use netdev_lockdep_set_classes(),
triggerring lockdep false positives.

WARNING: possible recursive locking detected
6.8.0-rc4-next-20240212-syzkaller #0 Not tainted

syz-executor.0/19016 is trying to acquire lock:
 ffff8880162cb298 (_xmit_ETHER#2){+.-.}-{2:2}, at: spin_lock include/linux/spinlock.h:351 [inline]
 ffff8880162cb298 (_xmit_ETHER#2){+.-.}-{2:2}, at: __netif_tx_lock include/linux/netdevice.h:4452 [inline]
 ffff8880162cb298 (_xmit_ETHER#2){+.-.}-{2:2}, at: sch_direct_xmit+0x1c4/0x5f0 net/sched/sch_generic.c:340

but task is already holding lock:
 ffff8880223db4d8 (_xmit_ETHER#2){+.-.}-{2:2}, at: spin_lock include/linux/spinlock.h:351 [inline]
 ffff8880223db4d8 (_xmit_ETHER#2){+.-.}-{2:2}, at: __netif_tx_lock include/linux/netdevice.h:4452 [inline]
 ffff8880223db4d8 (_xmit_ETHER#2){+.-.}-{2:2}, at: sch_direct_xmit+0x1c4/0x5f0 net/sched/sch_generic.c:340

other info that might help us debug this:
 Possible unsafe locking scenario:

       CPU0
  lock(_xmit_ETHER#2);
  lock(_xmit_ETHER#2);

 *** DEADLOCK ***

 May be due to missing lock nesting notation

9 locks held by syz-executor.0/19016:
  #0: ffffffff8f385208 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline]
  #0: ffffffff8f385208 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x82c/0x1040 net/core/rtnetlink.c:6603
  #1: ffffc90000a08c00 ((&in_dev->mr_ifc_timer)){+.-.}-{0:0}, at: call_timer_fn+0xc0/0x600 kernel/time/timer.c:1697
  #2: ffffffff8e131520 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:298 [inline]
  #2: ffffffff8e131520 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:750 [inline]
  #2: ffffffff8e131520 (rcu_read_lock){....}-{1:2}, at: ip_finish_output2+0x45f/0x1360 net/ipv4/ip_output.c:228
  #3: ffffffff8e131580 (rcu_read_lock_bh){....}-{1:2}, at: local_bh_disable include/linux/bottom_half.h:20 [inline]
  #3: ffffffff8e131580 (rcu_read_lock_bh){....}-{1:2}, at: rcu_read_lock_bh include/linux/rcupdate.h:802 [inline]
  #3: ffffffff8e131580 (rcu_read_lock_bh){....}-{1:2}, at: __dev_queue_xmit+0x2c4/0x3b10 net/core/dev.c:4284
  #4: ffff8880416e3258 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock){+...}-{2:2}, at: spin_trylock include/linux/spinlock.h:361 [inline]
  #4: ffff8880416e3258 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock){+...}-{2:2}, at: qdisc_run_begin include/net/sch_generic.h:195 [inline]
  #4: ffff8880416e3258 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock){+...}-{2:2}, at: __dev_xmit_skb net/core/dev.c:3771 [inline]
  #4: ffff8880416e3258 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock){+...}-{2:2}, at: __dev_queue_xmit+0x1262/0x3b10 net/core/dev.c:4325
  #5: ffff8880223db4d8 (_xmit_ETHER#2){+.-.}-{2:2}, at: spin_lock include/linux/spinlock.h:351 [inline]
  #5: ffff8880223db4d8 (_xmit_ETHER#2){+.-.}-{2:2}, at: __netif_tx_lock include/linux/netdevice.h:4452 [inline]
  #5: ffff8880223db4d8 (_xmit_ETHER#2){+.-.}-{2:2}, at: sch_direct_xmit+0x1c4/0x5f0 net/sched/sch_generic.c:340
  #6: ffffffff8e131520 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:298 [inline]
  #6: ffffffff8e131520 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:750 [inline]
  #6: ffffffff8e131520 (rcu_read_lock){....}-{1:2}, at: ip_finish_output2+0x45f/0x1360 net/ipv4/ip_output.c:228
  #7: ffffffff8e131580 (rcu_read_lock_bh){....}-{1:2}, at: local_bh_disable include/linux/bottom_half.h:20 [inline]
  #7: ffffffff8e131580 (rcu_read_lock_bh){....}-{1:2}, at: rcu_read_lock_bh include/linux/rcupdate.h:802 [inline]
  #7: ffffffff8e131580 (rcu_read_lock_bh){....}-{1:2}, at: __dev_queue_xmit+0x2c4/0x3b10 net/core/dev.c:4284
  #8: ffff888014d9d258 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock){+...}-{2:2}, at: spin_trylock include/linux/spinlock.h:361 [inline]
  #8: ffff888014d9d258 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock){+...}-{2:2}, at: qdisc_run_begin include/net/sch_generic.h:195 [inline]
  #8: ffff888014d9d258 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock){+...}-{2:2}, at: __dev_xmit_skb net/core/dev.c:3771 [inline]
  #8: ffff888014d9d258 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock){+...}-{2:2}, at: __dev_queue_xmit+0x1262/0x3b10 net/core/dev.c:4325

stack backtrace:
CPU: 1 PID: 19016 Comm: syz-executor.0 Not tainted 6.8.0-rc4-next-20240212-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024
Call Trace:
 <IRQ>
  __dump_stack lib/dump_stack.c:88 [inline]
  dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114
  check_deadlock kernel/locking/lockdep.c:3062 [inline]
  validate_chain+0x15c1/0x58e0 kernel/locking/lockdep.c:3856
  __lock_acquire+0x1346/0x1fd0 kernel/locking/lockdep.c:5137
  lock_acquire+0x1e4/0x530 kernel/locking/lockdep.c:5754
  __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline]
  _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154
  spin_lock include/linux/spinlock.h:351 [inline]
  __netif_tx_lock include/linux/netdevice.h:4452 [inline]
  sch_direct_xmit+0x1c4/0x5f0 net/sched/sch_generic.c:340
  __dev_xmit_skb net/core/dev.c:3784 [inline]
  __dev_queue_xmit+0x1912/0x3b10 net/core/dev.c:4325
  neigh_output include/net/neighbour.h:542 [inline]
  ip_finish_output2+0xe66/0x1360 net/ipv4/ip_output.c:235
  iptunnel_xmit+0x540/0x9b0 net/ipv4/ip_tunnel_core.c:82
  ip_tunnel_xmit+0x20ee/0x2960 net/ipv4/ip_tunnel.c:831
  erspan_xmit+0x9de/0x1460 net/ipv4/ip_gre.c:720
  __netdev_start_xmit include/linux/netdevice.h:4989 [inline]
  netdev_start_xmit include/linux/netdevice.h:5003 [inline]
  xmit_one net/core/dev.c:3555 [inline]
  dev_hard_start_xmit+0x242/0x770 net/core/dev.c:3571
  sch_direct_xmit+0x2b6/0x5f0 net/sched/sch_generic.c:342
  __dev_xmit_skb net/core/dev.c:3784 [inline]
  __dev_queue_xmit+0x1912/0x3b10 net/core/dev.c:4325
  neigh_output include/net/neighbour.h:542 [inline]
  ip_finish_output2+0xe66/0x1360 net/ipv4/ip_output.c:235
  igmpv3_send_cr net/ipv4/igmp.c:723 [inline]
  igmp_ifc_timer_expire+0xb71/0xd90 net/ipv4/igmp.c:813
  call_timer_fn+0x17e/0x600 kernel/time/timer.c:1700
  expire_timers kernel/time/timer.c:1751 [inline]
  __run_timers+0x621/0x830 kernel/time/timer.c:2038
  run_timer_softirq+0x67/0xf0 kernel/time/timer.c:2051
  __do_softirq+0x2bc/0x943 kernel/softirq.c:554
  invoke_softirq kernel/softirq.c:428 [inline]
  __irq_exit_rcu+0xf2/0x1c0 kernel/softirq.c:633
  irq_exit_rcu+0x9/0x30 kernel/softirq.c:645
  instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1076 [inline]
  sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1076
 </IRQ>
 <TASK>
  asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
 RIP: 0010:resched_offsets_ok kernel/sched/core.c:10127 [inline]
 RIP: 0010:__might_resched+0x16f/0x780 kernel/sched/core.c:10142
Code: 00 4c 89 e8 48 c1 e8 03 48 ba 00 00 00 00 00 fc ff df 48 89 44 24 38 0f b6 04 10 84 c0 0f 85 87 04 00 00 41 8b 45 00 c1 e0 08 <01> d8 44 39 e0 0f 85 d6 00 00 00 44 89 64 24 1c 48 8d bc 24 a0 00
RSP: 0018:ffffc9000ee069e0 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffff8880296a9e00
RDX: dffffc0000000000 RSI: ffff8880296a9e00 RDI: ffffffff8bfe8fa0
RBP: ffffc9000ee06b00 R08: ffffffff82326877 R09: 1ffff11002b5ad1b
R10: dffffc0000000000 R11: ffffed1002b5ad1c R12: 0000000000000000
R13: ffff8880296aa23c R14: 000000000000062a R15: 1ffff92001dc0d44
  down_write+0x19/0x50 kernel/locking/rwsem.c:1578
  kernfs_activate fs/kernfs/dir.c:1403 [inline]
  kernfs_add_one+0x4af/0x8b0 fs/kernfs/dir.c:819
  __kernfs_create_file+0x22e/0x2e0 fs/kernfs/file.c:1056
  sysfs_add_file_mode_ns+0x24a/0x310 fs/sysfs/file.c:307
  create_files fs/sysfs/group.c:64 [inline]
  internal_create_group+0x4f4/0xf20 fs/sysfs/group.c:152
  internal_create_groups fs/sysfs/group.c:192 [inline]
  sysfs_create_groups+0x56/0x120 fs/sysfs/group.c:218
  create_dir lib/kobject.c:78 [inline]
  kobject_add_internal+0x472/0x8d0 lib/kobject.c:240
  kobject_add_varg lib/kobject.c:374 [inline]
  kobject_init_and_add+0x124/0x190 lib/kobject.c:457
  netdev_queue_add_kobject net/core/net-sysfs.c:1706 [inline]
  netdev_queue_update_kobjects+0x1f3/0x480 net/core/net-sysfs.c:1758
  register_queue_kobjects net/core/net-sysfs.c:1819 [inline]
  netdev_register_kobject+0x265/0x310 net/core/net-sysfs.c:2059
  register_netdevice+0x1191/0x19c0 net/core/dev.c:10298
  bond_newlink+0x3b/0x90 drivers/net/bonding/bond_netlink.c:576
  rtnl_newlink_create net/core/rtnetlink.c:3506 [inline]
  __rtnl_newlink net/core/rtnetlink.c:3726 [inline]
  rtnl_newlink+0x158f/0x20a0 net/core/rtnetlink.c:3739
  rtnetlink_rcv_msg+0x885/0x1040 net/core/rtnetlink.c:6606
  netlink_rcv_skb+0x1e3/0x430 net/netlink/af_netlink.c:2543
  netlink_unicast_kernel net/netlink/af_netlink.c:1341 [inline]
  netlink_unicast+0x7ea/0x980 net/netlink/af_netlink.c:1367
  netlink_sendmsg+0xa3c/0xd70 net/netlink/af_netlink.c:1908
  sock_sendmsg_nosec net/socket.c:730 [inline]
  __sock_sendmsg+0x221/0x270 net/socket.c:745
  __sys_sendto+0x3a4/0x4f0 net/socket.c:2191
  __do_sys_sendto net/socket.c:2203 [inline]
  __se_sys_sendto net/socket.c:2199 [inline]
  __x64_sys_sendto+0xde/0x100 net/socket.c:2199
 do_syscall_64+0xfb/0x240
 entry_SYSCALL_64_after_hwframe+0x6d/0x75
RIP: 0033:0x7fc3fa87fa9c

Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/20240212140700.2795436-4-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
amboar pushed a commit that referenced this pull request Apr 15, 2024
[ Upstream commit 1947b92 ]

Parallel testing appears to show a race between allocating and setting
evsel ids. As there is a bounds check on the xyarray it yields a segv
like:

```
AddressSanitizer:DEADLYSIGNAL

=================================================================

==484408==ERROR: AddressSanitizer: SEGV on unknown address 0x000000000010

==484408==The signal is caused by a WRITE memory access.

==484408==Hint: address points to the zero page.

    #0 0x55cef5d4eff4 in perf_evlist__id_hash tools/lib/perf/evlist.c:256
    #1 0x55cef5d4f132 in perf_evlist__id_add tools/lib/perf/evlist.c:274
    #2 0x55cef5d4f545 in perf_evlist__id_add_fd tools/lib/perf/evlist.c:315
    #3 0x55cef5a1923f in store_evsel_ids util/evsel.c:3130
    #4 0x55cef5a19400 in evsel__store_ids util/evsel.c:3147
    #5 0x55cef5888204 in __run_perf_stat tools/perf/builtin-stat.c:832
    #6 0x55cef5888c06 in run_perf_stat tools/perf/builtin-stat.c:960
    #7 0x55cef58932db in cmd_stat tools/perf/builtin-stat.c:2878
...
```

Avoid this crash by early exiting the perf_evlist__id_add_fd and
perf_evlist__id_add is the access is out-of-bounds.

Signed-off-by: Ian Rogers <irogers@google.com>
Cc: Yang Jihong <yangjihong1@huawei.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/r/20240229070757.796244-1-irogers@google.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
amboar pushed a commit to amboar/linux that referenced this pull request Apr 15, 2024
The driver creates /sys/kernel/debug/dri/0/mob_ttm even when the
corresponding ttm_resource_manager is not allocated.
This leads to a crash when trying to read from this file.

Add a check to create mob_ttm, system_mob_ttm, and gmr_ttm debug file
only when the corresponding ttm_resource_manager is allocated.

crash> bt
PID: 3133409  TASK: ffff8fe4834a5000  CPU: 3    COMMAND: "grep"
 #0 [ffffb954506b3b20] machine_kexec at ffffffffb2a6bec3
 openbmc#1 [ffffb954506b3b78] __crash_kexec at ffffffffb2bb598a
 openbmc#2 [ffffb954506b3c38] crash_kexec at ffffffffb2bb68c1
 openbmc#3 [ffffb954506b3c50] oops_end at ffffffffb2a2a9b1
 openbmc#4 [ffffb954506b3c70] no_context at ffffffffb2a7e913
 openbmc#5 [ffffb954506b3cc8] __bad_area_nosemaphore at ffffffffb2a7ec8c
 openbmc#6 [ffffb954506b3d10] do_page_fault at ffffffffb2a7f887
 openbmc#7 [ffffb954506b3d40] page_fault at ffffffffb360116e
    [exception RIP: ttm_resource_manager_debug+0x11]
    RIP: ffffffffc04afd11  RSP: ffffb954506b3df0  RFLAGS: 00010246
    RAX: ffff8fe41a6d1200  RBX: 0000000000000000  RCX: 0000000000000940
    RDX: 0000000000000000  RSI: ffffffffc04b4338  RDI: 0000000000000000
    RBP: ffffb954506b3e08   R8: ffff8fee3ffad000   R9: 0000000000000000
    R10: ffff8fe41a76a000  R11: 0000000000000001  R12: 00000000ffffffff
    R13: 0000000000000001  R14: ffff8fe5bb6f3900  R15: ffff8fe41a6d1200
    ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0018
 openbmc#8 [ffffb954506b3e00] ttm_resource_manager_show at ffffffffc04afde7 [ttm]
 openbmc#9 [ffffb954506b3e30] seq_read at ffffffffb2d8f9f3
    RIP: 00007f4c4eda8985  RSP: 00007ffdbba9e9f8  RFLAGS: 00000246
    RAX: ffffffffffffffda  RBX: 000000000037e000  RCX: 00007f4c4eda8985
    RDX: 000000000037e000  RSI: 00007f4c41573000  RDI: 0000000000000003
    RBP: 000000000037e000   R8: 0000000000000000   R9: 000000000037fe30
    R10: 0000000000000000  R11: 0000000000000246  R12: 00007f4c41573000
    R13: 0000000000000003  R14: 00007f4c41572010  R15: 0000000000000003
    ORIG_RAX: 0000000000000000  CS: 0033  SS: 002b

Signed-off-by: Jocelyn Falempe <jfalempe@redhat.com>
Fixes: af4a25b ("drm/vmwgfx: Add debugfs entries for various ttm resource managers")
Cc: <stable@vger.kernel.org>
Reviewed-by: Zack Rusin <zack.rusin@broadcom.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240312093551.196609-1-jfalempe@redhat.com
amboar pushed a commit that referenced this pull request Apr 29, 2024
[ Upstream commit f8bbc07 ]

vhost_worker will call tun call backs to receive packets. If too many
illegal packets arrives, tun_do_read will keep dumping packet contents.
When console is enabled, it will costs much more cpu time to dump
packet and soft lockup will be detected.

net_ratelimit mechanism can be used to limit the dumping rate.

PID: 33036    TASK: ffff949da6f20000  CPU: 23   COMMAND: "vhost-32980"
 #0 [fffffe00003fce50] crash_nmi_callback at ffffffff89249253
 #1 [fffffe00003fce58] nmi_handle at ffffffff89225fa3
 #2 [fffffe00003fceb0] default_do_nmi at ffffffff8922642e
 #3 [fffffe00003fced0] do_nmi at ffffffff8922660d
 #4 [fffffe00003fcef0] end_repeat_nmi at ffffffff89c01663
    [exception RIP: io_serial_in+20]
    RIP: ffffffff89792594  RSP: ffffa655314979e8  RFLAGS: 00000002
    RAX: ffffffff89792500  RBX: ffffffff8af428a0  RCX: 0000000000000000
    RDX: 00000000000003fd  RSI: 0000000000000005  RDI: ffffffff8af428a0
    RBP: 0000000000002710   R8: 0000000000000004   R9: 000000000000000f
    R10: 0000000000000000  R11: ffffffff8acbf64f  R12: 0000000000000020
    R13: ffffffff8acbf698  R14: 0000000000000058  R15: 0000000000000000
    ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0018
 #5 [ffffa655314979e8] io_serial_in at ffffffff89792594
 #6 [ffffa655314979e8] wait_for_xmitr at ffffffff89793470
 #7 [ffffa65531497a08] serial8250_console_putchar at ffffffff897934f6
 #8 [ffffa65531497a20] uart_console_write at ffffffff8978b605
 #9 [ffffa65531497a48] serial8250_console_write at ffffffff89796558
 #10 [ffffa65531497ac8] console_unlock at ffffffff89316124
 #11 [ffffa65531497b10] vprintk_emit at ffffffff89317c07
 #12 [ffffa65531497b68] printk at ffffffff89318306
 #13 [ffffa65531497bc8] print_hex_dump at ffffffff89650765
 #14 [ffffa65531497ca8] tun_do_read at ffffffffc0b06c27 [tun]
 #15 [ffffa65531497d38] tun_recvmsg at ffffffffc0b06e34 [tun]
 #16 [ffffa65531497d68] handle_rx at ffffffffc0c5d682 [vhost_net]
 #17 [ffffa65531497ed0] vhost_worker at ffffffffc0c644dc [vhost]
 #18 [ffffa65531497f10] kthread at ffffffff892d2e72
 #19 [ffffa65531497f50] ret_from_fork at ffffffff89c0022f

Fixes: ef3db4a ("tun: avoid BUG, dump packet on GSO errors")
Signed-off-by: Lei Chen <lei.chen@smartx.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Link: https://lore.kernel.org/r/20240415020247.2207781-1-lei.chen@smartx.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
amboar pushed a commit that referenced this pull request Apr 29, 2024
commit 9e985cb upstream.

Drop support for virtualizing adaptive PEBS, as KVM's implementation is
architecturally broken without an obvious/easy path forward, and because
exposing adaptive PEBS can leak host LBRs to the guest, i.e. can leak
host kernel addresses to the guest.

Bug #1 is that KVM doesn't account for the upper 32 bits of
IA32_FIXED_CTR_CTRL when (re)programming fixed counters, e.g
fixed_ctrl_field() drops the upper bits, reprogram_fixed_counters()
stores local variables as u8s and truncates the upper bits too, etc.

Bug #2 is that, because KVM _always_ sets precise_ip to a non-zero value
for PEBS events, perf will _always_ generate an adaptive record, even if
the guest requested a basic record.  Note, KVM will also enable adaptive
PEBS in individual *counter*, even if adaptive PEBS isn't exposed to the
guest, but this is benign as MSR_PEBS_DATA_CFG is guaranteed to be zero,
i.e. the guest will only ever see Basic records.

Bug #3 is in perf.  intel_pmu_disable_fixed() doesn't clear the upper
bits either, i.e. leaves ICL_FIXED_0_ADAPTIVE set, and
intel_pmu_enable_fixed() effectively doesn't clear ICL_FIXED_0_ADAPTIVE
either.  I.e. perf _always_ enables ADAPTIVE counters, regardless of what
KVM requests.

Bug #4 is that adaptive PEBS *might* effectively bypass event filters set
by the host, as "Updated Memory Access Info Group" records information
that might be disallowed by userspace via KVM_SET_PMU_EVENT_FILTER.

Bug #5 is that KVM doesn't ensure LBR MSRs hold guest values (or at least
zeros) when entering a vCPU with adaptive PEBS, which allows the guest
to read host LBRs, i.e. host RIPs/addresses, by enabling "LBR Entries"
records.

Disable adaptive PEBS support as an immediate fix due to the severity of
the LBR leak in particular, and because fixing all of the bugs will be
non-trivial, e.g. not suitable for backporting to stable kernels.

Note!  This will break live migration, but trying to make KVM play nice
with live migration would be quite complicated, wouldn't be guaranteed to
work (i.e. KVM might still kill/confuse the guest), and it's not clear
that there are any publicly available VMMs that support adaptive PEBS,
let alone live migrate VMs that support adaptive PEBS, e.g. QEMU doesn't
support PEBS in any capacity.

Link: https://lore.kernel.org/all/20240306230153.786365-1-seanjc@google.com
Link: https://lore.kernel.org/all/ZeepGjHCeSfadANM@google.com
Fixes: c59a1f1 ("KVM: x86/pmu: Add IA32_PEBS_ENABLE MSR emulation for extended PEBS")
Cc: stable@vger.kernel.org
Cc: Like Xu <like.xu.linux@gmail.com>
Cc: Mingwei Zhang <mizhang@google.com>
Cc: Zhenyu Wang <zhenyuw@linux.intel.com>
Cc: Zhang Xiong <xiong.y.zhang@intel.com>
Cc: Lv Zhiyuan <zhiyuan.lv@intel.com>
Cc: Dapeng Mi <dapeng1.mi@intel.com>
Cc: Jim Mattson <jmattson@google.com>
Acked-by: Like Xu <likexu@tencent.com>
Link: https://lore.kernel.org/r/20240307005833.827147-1-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
amboar pushed a commit that referenced this pull request Apr 29, 2024
commit 89f9a1e upstream.

On the time to free xbc memory in xbc_exit(), memblock may has handed
over memory to buddy allocator. So it doesn't make sense to free memory
back to memblock. memblock_free() called by xbc_exit() even causes UAF bugs
on architectures with CONFIG_ARCH_KEEP_MEMBLOCK disabled like x86.
Following KASAN logs shows this case.

This patch fixes the xbc memory free problem by calling memblock_free()
in early xbc init error rewind path and calling memblock_free_late() in
xbc exit path to free memory to buddy allocator.

[    9.410890] ==================================================================
[    9.418962] BUG: KASAN: use-after-free in memblock_isolate_range+0x12d/0x260
[    9.426850] Read of size 8 at addr ffff88845dd30000 by task swapper/0/1

[    9.435901] CPU: 9 PID: 1 Comm: swapper/0 Tainted: G     U             6.9.0-rc3-00208-g586b5dfb51b9 #5
[    9.446403] Hardware name: Intel Corporation RPLP LP5 (CPU:RaptorLake)/RPLP LP5 (ID:13), BIOS IRPPN02.01.01.00.00.19.015.D-00000000 Dec 28 2023
[    9.460789] Call Trace:
[    9.463518]  <TASK>
[    9.465859]  dump_stack_lvl+0x53/0x70
[    9.469949]  print_report+0xce/0x610
[    9.473944]  ? __virt_addr_valid+0xf5/0x1b0
[    9.478619]  ? memblock_isolate_range+0x12d/0x260
[    9.483877]  kasan_report+0xc6/0x100
[    9.487870]  ? memblock_isolate_range+0x12d/0x260
[    9.493125]  memblock_isolate_range+0x12d/0x260
[    9.498187]  memblock_phys_free+0xb4/0x160
[    9.502762]  ? __pfx_memblock_phys_free+0x10/0x10
[    9.508021]  ? mutex_unlock+0x7e/0xd0
[    9.512111]  ? __pfx_mutex_unlock+0x10/0x10
[    9.516786]  ? kernel_init_freeable+0x2d4/0x430
[    9.521850]  ? __pfx_kernel_init+0x10/0x10
[    9.526426]  xbc_exit+0x17/0x70
[    9.529935]  kernel_init+0x38/0x1e0
[    9.533829]  ? _raw_spin_unlock_irq+0xd/0x30
[    9.538601]  ret_from_fork+0x2c/0x50
[    9.542596]  ? __pfx_kernel_init+0x10/0x10
[    9.547170]  ret_from_fork_asm+0x1a/0x30
[    9.551552]  </TASK>

[    9.555649] The buggy address belongs to the physical page:
[    9.561875] page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x1 pfn:0x45dd30
[    9.570821] flags: 0x200000000000000(node=0|zone=2)
[    9.576271] page_type: 0xffffffff()
[    9.580167] raw: 0200000000000000 ffffea0011774c48 ffffea0012ba1848 0000000000000000
[    9.588823] raw: 0000000000000001 0000000000000000 00000000ffffffff 0000000000000000
[    9.597476] page dumped because: kasan: bad access detected

[    9.605362] Memory state around the buggy address:
[    9.610714]  ffff88845dd2ff00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[    9.618786]  ffff88845dd2ff80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[    9.626857] >ffff88845dd30000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
[    9.634930]                    ^
[    9.638534]  ffff88845dd30080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
[    9.646605]  ffff88845dd30100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
[    9.654675] ==================================================================

Link: https://lore.kernel.org/all/20240414114944.1012359-1-qiang4.zhang@linux.intel.com/

Fixes: 40caa12 ("init: bootconfig: Remove all bootconfig data when the init memory is removed")
Cc: Stable@vger.kernel.org
Signed-off-by: Qiang Zhang <qiang4.zhang@intel.com>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
amboar pushed a commit to amboar/linux that referenced this pull request May 1, 2024
…git/netfilter/nf

Pablo Neira Ayuso says:

====================
Netfilter fixes for net

The following patchset contains Netfilter fixes for net:

Patch openbmc#1 unlike early commit path stage which triggers a call to abort,
         an explicit release of the batch is required on abort, otherwise
         mutex is released and commit_list remains in place.

Patch openbmc#2 release mutex after nft_gc_seq_end() in commit path, otherwise
         async GC worker could collect expired objects.

Patch openbmc#3 flush pending destroy work in module removal path, otherwise UaF
         is possible.

Patch openbmc#4 and openbmc#6 restrict the table dormant flag with basechain updates
	 to fix state inconsistency in the hook registration.

Patch openbmc#5 adds missing RCU read side lock to flowtable type to avoid races
	 with module removal.

* tag 'nf-24-04-04' of git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf:
  netfilter: nf_tables: discard table flag update with pending basechain deletion
  netfilter: nf_tables: Fix potential data-race in __nft_flowtable_type_get()
  netfilter: nf_tables: reject new basechain after table flag update
  netfilter: nf_tables: flush pending destroy work before exit_net release
  netfilter: nf_tables: release mutex after nft_gc_seq_end from abort path
  netfilter: nf_tables: release batch on table validation from abort path
====================

Link: https://lore.kernel.org/r/20240404104334.1627-1-pablo@netfilter.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
amboar pushed a commit to amboar/linux that referenced this pull request May 1, 2024
Drop support for virtualizing adaptive PEBS, as KVM's implementation is
architecturally broken without an obvious/easy path forward, and because
exposing adaptive PEBS can leak host LBRs to the guest, i.e. can leak
host kernel addresses to the guest.

Bug openbmc#1 is that KVM doesn't account for the upper 32 bits of
IA32_FIXED_CTR_CTRL when (re)programming fixed counters, e.g
fixed_ctrl_field() drops the upper bits, reprogram_fixed_counters()
stores local variables as u8s and truncates the upper bits too, etc.

Bug openbmc#2 is that, because KVM _always_ sets precise_ip to a non-zero value
for PEBS events, perf will _always_ generate an adaptive record, even if
the guest requested a basic record.  Note, KVM will also enable adaptive
PEBS in individual *counter*, even if adaptive PEBS isn't exposed to the
guest, but this is benign as MSR_PEBS_DATA_CFG is guaranteed to be zero,
i.e. the guest will only ever see Basic records.

Bug openbmc#3 is in perf.  intel_pmu_disable_fixed() doesn't clear the upper
bits either, i.e. leaves ICL_FIXED_0_ADAPTIVE set, and
intel_pmu_enable_fixed() effectively doesn't clear ICL_FIXED_0_ADAPTIVE
either.  I.e. perf _always_ enables ADAPTIVE counters, regardless of what
KVM requests.

Bug openbmc#4 is that adaptive PEBS *might* effectively bypass event filters set
by the host, as "Updated Memory Access Info Group" records information
that might be disallowed by userspace via KVM_SET_PMU_EVENT_FILTER.

Bug openbmc#5 is that KVM doesn't ensure LBR MSRs hold guest values (or at least
zeros) when entering a vCPU with adaptive PEBS, which allows the guest
to read host LBRs, i.e. host RIPs/addresses, by enabling "LBR Entries"
records.

Disable adaptive PEBS support as an immediate fix due to the severity of
the LBR leak in particular, and because fixing all of the bugs will be
non-trivial, e.g. not suitable for backporting to stable kernels.

Note!  This will break live migration, but trying to make KVM play nice
with live migration would be quite complicated, wouldn't be guaranteed to
work (i.e. KVM might still kill/confuse the guest), and it's not clear
that there are any publicly available VMMs that support adaptive PEBS,
let alone live migrate VMs that support adaptive PEBS, e.g. QEMU doesn't
support PEBS in any capacity.

Link: https://lore.kernel.org/all/20240306230153.786365-1-seanjc@google.com
Link: https://lore.kernel.org/all/ZeepGjHCeSfadANM@google.com
Fixes: c59a1f1 ("KVM: x86/pmu: Add IA32_PEBS_ENABLE MSR emulation for extended PEBS")
Cc: stable@vger.kernel.org
Cc: Like Xu <like.xu.linux@gmail.com>
Cc: Mingwei Zhang <mizhang@google.com>
Cc: Zhenyu Wang <zhenyuw@linux.intel.com>
Cc: Zhang Xiong <xiong.y.zhang@intel.com>
Cc: Lv Zhiyuan <zhiyuan.lv@intel.com>
Cc: Dapeng Mi <dapeng1.mi@intel.com>
Cc: Jim Mattson <jmattson@google.com>
Acked-by: Like Xu <likexu@tencent.com>
Link: https://lore.kernel.org/r/20240307005833.827147-1-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
amboar pushed a commit to amboar/linux that referenced this pull request May 1, 2024
…git/netfilter/nf

netfilter pull request 24-04-11

Pablo Neira Ayuso says:

====================
Netfilter fixes for net

The following patchset contains Netfilter fixes for net:

Patches openbmc#1 and openbmc#2 add missing rcu read side lock when iterating over
expression and object type list which could race with module removal.

Patch openbmc#3 prevents promisc packet from visiting the bridge/input hook
	 to amend a recent fix to address conntrack confirmation race
	 in br_netfilter and nf_conntrack_bridge.

Patch openbmc#4 adds and uses iterate decorator type to fetch the current
	 pipapo set backend datastructure view when netlink dumps the
	 set elements.

Patch openbmc#5 fixes removal of duplicate elements in the pipapo set backend.

Patch openbmc#6 flowtable validates pppoe header before accessing it.

Patch openbmc#7 fixes flowtable datapath for pppoe packets, otherwise lookup
         fails and pppoe packets follow classic path.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
amboar pushed a commit to amboar/linux that referenced this pull request May 1, 2024
On the time to free xbc memory in xbc_exit(), memblock may has handed
over memory to buddy allocator. So it doesn't make sense to free memory
back to memblock. memblock_free() called by xbc_exit() even causes UAF bugs
on architectures with CONFIG_ARCH_KEEP_MEMBLOCK disabled like x86.
Following KASAN logs shows this case.

This patch fixes the xbc memory free problem by calling memblock_free()
in early xbc init error rewind path and calling memblock_free_late() in
xbc exit path to free memory to buddy allocator.

[    9.410890] ==================================================================
[    9.418962] BUG: KASAN: use-after-free in memblock_isolate_range+0x12d/0x260
[    9.426850] Read of size 8 at addr ffff88845dd30000 by task swapper/0/1

[    9.435901] CPU: 9 PID: 1 Comm: swapper/0 Tainted: G     U             6.9.0-rc3-00208-g586b5dfb51b9 openbmc#5
[    9.446403] Hardware name: Intel Corporation RPLP LP5 (CPU:RaptorLake)/RPLP LP5 (ID:13), BIOS IRPPN02.01.01.00.00.19.015.D-00000000 Dec 28 2023
[    9.460789] Call Trace:
[    9.463518]  <TASK>
[    9.465859]  dump_stack_lvl+0x53/0x70
[    9.469949]  print_report+0xce/0x610
[    9.473944]  ? __virt_addr_valid+0xf5/0x1b0
[    9.478619]  ? memblock_isolate_range+0x12d/0x260
[    9.483877]  kasan_report+0xc6/0x100
[    9.487870]  ? memblock_isolate_range+0x12d/0x260
[    9.493125]  memblock_isolate_range+0x12d/0x260
[    9.498187]  memblock_phys_free+0xb4/0x160
[    9.502762]  ? __pfx_memblock_phys_free+0x10/0x10
[    9.508021]  ? mutex_unlock+0x7e/0xd0
[    9.512111]  ? __pfx_mutex_unlock+0x10/0x10
[    9.516786]  ? kernel_init_freeable+0x2d4/0x430
[    9.521850]  ? __pfx_kernel_init+0x10/0x10
[    9.526426]  xbc_exit+0x17/0x70
[    9.529935]  kernel_init+0x38/0x1e0
[    9.533829]  ? _raw_spin_unlock_irq+0xd/0x30
[    9.538601]  ret_from_fork+0x2c/0x50
[    9.542596]  ? __pfx_kernel_init+0x10/0x10
[    9.547170]  ret_from_fork_asm+0x1a/0x30
[    9.551552]  </TASK>

[    9.555649] The buggy address belongs to the physical page:
[    9.561875] page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x1 pfn:0x45dd30
[    9.570821] flags: 0x200000000000000(node=0|zone=2)
[    9.576271] page_type: 0xffffffff()
[    9.580167] raw: 0200000000000000 ffffea0011774c48 ffffea0012ba1848 0000000000000000
[    9.588823] raw: 0000000000000001 0000000000000000 00000000ffffffff 0000000000000000
[    9.597476] page dumped because: kasan: bad access detected

[    9.605362] Memory state around the buggy address:
[    9.610714]  ffff88845dd2ff00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[    9.618786]  ffff88845dd2ff80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[    9.626857] >ffff88845dd30000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
[    9.634930]                    ^
[    9.638534]  ffff88845dd30080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
[    9.646605]  ffff88845dd30100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
[    9.654675] ==================================================================

Link: https://lore.kernel.org/all/20240414114944.1012359-1-qiang4.zhang@linux.intel.com/

Fixes: 40caa12 ("init: bootconfig: Remove all bootconfig data when the init memory is removed")
Cc: Stable@vger.kernel.org
Signed-off-by: Qiang Zhang <qiang4.zhang@intel.com>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
amboar pushed a commit to amboar/linux that referenced this pull request May 1, 2024
vhost_worker will call tun call backs to receive packets. If too many
illegal packets arrives, tun_do_read will keep dumping packet contents.
When console is enabled, it will costs much more cpu time to dump
packet and soft lockup will be detected.

net_ratelimit mechanism can be used to limit the dumping rate.

PID: 33036    TASK: ffff949da6f20000  CPU: 23   COMMAND: "vhost-32980"
 #0 [fffffe00003fce50] crash_nmi_callback at ffffffff89249253
 openbmc#1 [fffffe00003fce58] nmi_handle at ffffffff89225fa3
 openbmc#2 [fffffe00003fceb0] default_do_nmi at ffffffff8922642e
 openbmc#3 [fffffe00003fced0] do_nmi at ffffffff8922660d
 openbmc#4 [fffffe00003fcef0] end_repeat_nmi at ffffffff89c01663
    [exception RIP: io_serial_in+20]
    RIP: ffffffff89792594  RSP: ffffa655314979e8  RFLAGS: 00000002
    RAX: ffffffff89792500  RBX: ffffffff8af428a0  RCX: 0000000000000000
    RDX: 00000000000003fd  RSI: 0000000000000005  RDI: ffffffff8af428a0
    RBP: 0000000000002710   R8: 0000000000000004   R9: 000000000000000f
    R10: 0000000000000000  R11: ffffffff8acbf64f  R12: 0000000000000020
    R13: ffffffff8acbf698  R14: 0000000000000058  R15: 0000000000000000
    ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0018
 openbmc#5 [ffffa655314979e8] io_serial_in at ffffffff89792594
 openbmc#6 [ffffa655314979e8] wait_for_xmitr at ffffffff89793470
 openbmc#7 [ffffa65531497a08] serial8250_console_putchar at ffffffff897934f6
 openbmc#8 [ffffa65531497a20] uart_console_write at ffffffff8978b605
 openbmc#9 [ffffa65531497a48] serial8250_console_write at ffffffff89796558
 openbmc#10 [ffffa65531497ac8] console_unlock at ffffffff89316124
 openbmc#11 [ffffa65531497b10] vprintk_emit at ffffffff89317c07
 openbmc#12 [ffffa65531497b68] printk at ffffffff89318306
 openbmc#13 [ffffa65531497bc8] print_hex_dump at ffffffff89650765
 openbmc#14 [ffffa65531497ca8] tun_do_read at ffffffffc0b06c27 [tun]
 openbmc#15 [ffffa65531497d38] tun_recvmsg at ffffffffc0b06e34 [tun]
 openbmc#16 [ffffa65531497d68] handle_rx at ffffffffc0c5d682 [vhost_net]
 openbmc#17 [ffffa65531497ed0] vhost_worker at ffffffffc0c644dc [vhost]
 openbmc#18 [ffffa65531497f10] kthread at ffffffff892d2e72
 openbmc#19 [ffffa65531497f50] ret_from_fork at ffffffff89c0022f

Fixes: ef3db4a ("tun: avoid BUG, dump packet on GSO errors")
Signed-off-by: Lei Chen <lei.chen@smartx.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Link: https://lore.kernel.org/r/20240415020247.2207781-1-lei.chen@smartx.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
amboar pushed a commit to amboar/linux that referenced this pull request May 1, 2024
The rehash delayed work migrates filters from one region to another
according to the number of available credits.

The migrated from region is destroyed at the end of the work if the
number of credits is non-negative as the assumption is that this is
indicative of migration being complete. This assumption is incorrect as
a non-negative number of credits can also be the result of a failed
migration.

The destruction of a region that still has filters referencing it can
result in a use-after-free [1].

Fix by not destroying the region if migration failed.

[1]
BUG: KASAN: slab-use-after-free in mlxsw_sp_acl_ctcam_region_entry_remove+0x21d/0x230
Read of size 8 at addr ffff8881735319e8 by task kworker/0:31/3858

CPU: 0 PID: 3858 Comm: kworker/0:31 Tainted: G        W          6.9.0-rc2-custom-00782-gf2275c2157d8 openbmc#5
Hardware name: Mellanox Technologies Ltd. MSN3700/VMOD0005, BIOS 5.11 01/06/2019
Workqueue: mlxsw_core mlxsw_sp_acl_tcam_vregion_rehash_work
Call Trace:
 <TASK>
 dump_stack_lvl+0xc6/0x120
 print_report+0xce/0x670
 kasan_report+0xd7/0x110
 mlxsw_sp_acl_ctcam_region_entry_remove+0x21d/0x230
 mlxsw_sp_acl_ctcam_entry_del+0x2e/0x70
 mlxsw_sp_acl_atcam_entry_del+0x81/0x210
 mlxsw_sp_acl_tcam_vchunk_migrate_all+0x3cd/0xb50
 mlxsw_sp_acl_tcam_vregion_rehash_work+0x157/0x1300
 process_one_work+0x8eb/0x19b0
 worker_thread+0x6c9/0xf70
 kthread+0x2c9/0x3b0
 ret_from_fork+0x4d/0x80
 ret_from_fork_asm+0x1a/0x30
 </TASK>

Allocated by task 174:
 kasan_save_stack+0x33/0x60
 kasan_save_track+0x14/0x30
 __kasan_kmalloc+0x8f/0xa0
 __kmalloc+0x19c/0x360
 mlxsw_sp_acl_tcam_region_create+0xdf/0x9c0
 mlxsw_sp_acl_tcam_vregion_rehash_work+0x954/0x1300
 process_one_work+0x8eb/0x19b0
 worker_thread+0x6c9/0xf70
 kthread+0x2c9/0x3b0
 ret_from_fork+0x4d/0x80
 ret_from_fork_asm+0x1a/0x30

Freed by task 7:
 kasan_save_stack+0x33/0x60
 kasan_save_track+0x14/0x30
 kasan_save_free_info+0x3b/0x60
 poison_slab_object+0x102/0x170
 __kasan_slab_free+0x14/0x30
 kfree+0xc1/0x290
 mlxsw_sp_acl_tcam_region_destroy+0x272/0x310
 mlxsw_sp_acl_tcam_vregion_rehash_work+0x731/0x1300
 process_one_work+0x8eb/0x19b0
 worker_thread+0x6c9/0xf70
 kthread+0x2c9/0x3b0
 ret_from_fork+0x4d/0x80
 ret_from_fork_asm+0x1a/0x30

Fixes: c9c9af9 ("mlxsw: spectrum_acl: Allow to interrupt/continue rehash work")
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Tested-by: Alexander Zubkov <green@qrator.net>
Reviewed-by: Petr Machata <petrm@nvidia.com>
Signed-off-by: Petr Machata <petrm@nvidia.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://lore.kernel.org/r/3e412b5659ec2310c5c615760dfe5eac18dd7ebd.1713797103.git.petrm@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
amboar pushed a commit that referenced this pull request May 3, 2024
[ Upstream commit 5422598 ]

The rehash delayed work migrates filters from one region to another
according to the number of available credits.

The migrated from region is destroyed at the end of the work if the
number of credits is non-negative as the assumption is that this is
indicative of migration being complete. This assumption is incorrect as
a non-negative number of credits can also be the result of a failed
migration.

The destruction of a region that still has filters referencing it can
result in a use-after-free [1].

Fix by not destroying the region if migration failed.

[1]
BUG: KASAN: slab-use-after-free in mlxsw_sp_acl_ctcam_region_entry_remove+0x21d/0x230
Read of size 8 at addr ffff8881735319e8 by task kworker/0:31/3858

CPU: 0 PID: 3858 Comm: kworker/0:31 Tainted: G        W          6.9.0-rc2-custom-00782-gf2275c2157d8 #5
Hardware name: Mellanox Technologies Ltd. MSN3700/VMOD0005, BIOS 5.11 01/06/2019
Workqueue: mlxsw_core mlxsw_sp_acl_tcam_vregion_rehash_work
Call Trace:
 <TASK>
 dump_stack_lvl+0xc6/0x120
 print_report+0xce/0x670
 kasan_report+0xd7/0x110
 mlxsw_sp_acl_ctcam_region_entry_remove+0x21d/0x230
 mlxsw_sp_acl_ctcam_entry_del+0x2e/0x70
 mlxsw_sp_acl_atcam_entry_del+0x81/0x210
 mlxsw_sp_acl_tcam_vchunk_migrate_all+0x3cd/0xb50
 mlxsw_sp_acl_tcam_vregion_rehash_work+0x157/0x1300
 process_one_work+0x8eb/0x19b0
 worker_thread+0x6c9/0xf70
 kthread+0x2c9/0x3b0
 ret_from_fork+0x4d/0x80
 ret_from_fork_asm+0x1a/0x30
 </TASK>

Allocated by task 174:
 kasan_save_stack+0x33/0x60
 kasan_save_track+0x14/0x30
 __kasan_kmalloc+0x8f/0xa0
 __kmalloc+0x19c/0x360
 mlxsw_sp_acl_tcam_region_create+0xdf/0x9c0
 mlxsw_sp_acl_tcam_vregion_rehash_work+0x954/0x1300
 process_one_work+0x8eb/0x19b0
 worker_thread+0x6c9/0xf70
 kthread+0x2c9/0x3b0
 ret_from_fork+0x4d/0x80
 ret_from_fork_asm+0x1a/0x30

Freed by task 7:
 kasan_save_stack+0x33/0x60
 kasan_save_track+0x14/0x30
 kasan_save_free_info+0x3b/0x60
 poison_slab_object+0x102/0x170
 __kasan_slab_free+0x14/0x30
 kfree+0xc1/0x290
 mlxsw_sp_acl_tcam_region_destroy+0x272/0x310
 mlxsw_sp_acl_tcam_vregion_rehash_work+0x731/0x1300
 process_one_work+0x8eb/0x19b0
 worker_thread+0x6c9/0xf70
 kthread+0x2c9/0x3b0
 ret_from_fork+0x4d/0x80
 ret_from_fork_asm+0x1a/0x30

Fixes: c9c9af9 ("mlxsw: spectrum_acl: Allow to interrupt/continue rehash work")
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Tested-by: Alexander Zubkov <green@qrator.net>
Reviewed-by: Petr Machata <petrm@nvidia.com>
Signed-off-by: Petr Machata <petrm@nvidia.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://lore.kernel.org/r/3e412b5659ec2310c5c615760dfe5eac18dd7ebd.1713797103.git.petrm@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
dkodihal pushed a commit to NVIDIA/linux that referenced this pull request May 7, 2024
Use memset_io() for DMA_MEMORY_IO mappings which are mapped as I/O
memory, and regular memset() for DMA_MEMORY_MAP mappings.

This fixes the below alignment fault on arm64 for DMA_MEMORY_IO
mappings, where memset() uses the DC ZVA instruction which is invalid on
device memory.

   Unhandled fault: alignment fault (0x96000061) at 0xffffff8000380000
   Internal error: : 96000061 [openbmc#1] PREEMPT SMP
   Modules linked in: hdlcd(+) clk_scpi
   CPU: 4 PID: 1355 Comm: systemd-udevd Not tainted 4.4.0-rc1+ openbmc#5
   Hardware name: ARM Juno development board (r0) (DT)
   task: ffffffc9763eee00 ti: ffffffc9758c4000 task.ti: ffffffc9758c4000
   PC is at __efistub_memset+0x1ac/0x200
   LR is at dma_alloc_from_coherent+0xb0/0x120
   pc : [<ffffffc00030ff2c>] lr : [<ffffffc00042a918>] pstate: 400001c5
   sp : ffffffc9758c79a0
   x29: ffffffc9758c79a0 x28: ffffffc000635cd0
   x27: 0000000000000124 x26: ffffffc000119ef4
   x25: 0000000000010000 x24: 0000000000000140
   x23: ffffffc07e9ac3a8 x22: ffffffc9758c7a58
   x21: ffffffc9758c7a68 x20: 0000000000000004
   x19: ffffffc07e9ac380 x18: 0000000000000001
   x17: 0000007fae1bbba8 x16: ffffffc0001b2d1c
   x15: ffffffffffffffff x14: 0ffffffffffffffe
   x13: 0000000000000010 x12: ffffff800837ffff
   x11: ffffff800837ffff x10: 0000000040000000
   x9 : 0000000000000000 x8 : ffffff8000380000
   x7 : 0000000000000000 x6 : 000000000000003f
   x5 : 0000000000000040 x4 : 0000000000000000
   x3 : 0000000000000004 x2 : 000000000000ffc0
   x1 : 0000000000000000 x0 : ffffff8000380000

Signed-off-by: Brian Starkey <brian.starkey@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
dkodihal pushed a commit to NVIDIA/linux that referenced this pull request May 7, 2024
…eservation

Even if isochronous resources reservation fails, error code doesn't return
in pcm.hw_params callback.

Cc: <stable@vger.kernel.org> openbmc#5.3+
Fixes: 4f380d0 ("ALSA: oxfw: configure packet format in pcm.hw_params callback")
Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Link: https://lore.kernel.org/r/20191209151655.GA8090@workstation
Signed-off-by: Takashi Iwai <tiwai@suse.de>
dkodihal pushed a commit to NVIDIA/linux that referenced this pull request May 7, 2024
…es reservation

Even if isochronous resources reservation fails, error code doesn't return
in pcm.hw_params callback.

Cc: <stable@vger.kernel.org> openbmc#5.3+
Fixes: 55162d2 ("ALSA: fireface: reserve/release isochronous resources in pcm.hw_params/hw_free callbacks")
Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Link: https://lore.kernel.org/r/20191209151655.GA8090@workstation
Signed-off-by: Takashi Iwai <tiwai@suse.de>
amboar pushed a commit that referenced this pull request Jun 13, 2024
commit c2274b9 upstream.

The reader code in rb_get_reader_page() swaps a new reader page into the
ring buffer by doing cmpxchg on old->list.prev->next to point it to the
new page. Following that, if the operation is successful,
old->list.next->prev gets updated too. This means the underlying
doubly-linked list is temporarily inconsistent, page->prev->next or
page->next->prev might not be equal back to page for some page in the
ring buffer.

The resize operation in ring_buffer_resize() can be invoked in parallel.
It calls rb_check_pages() which can detect the described inconsistency
and stop further tracing:

[  190.271762] ------------[ cut here ]------------
[  190.271771] WARNING: CPU: 1 PID: 6186 at kernel/trace/ring_buffer.c:1467 rb_check_pages.isra.0+0x6a/0xa0
[  190.271789] Modules linked in: [...]
[  190.271991] Unloaded tainted modules: intel_uncore_frequency(E):1 skx_edac(E):1
[  190.272002] CPU: 1 PID: 6186 Comm: cmd.sh Kdump: loaded Tainted: G            E      6.9.0-rc6-default #5 158d3e1e6d0b091c34c3b96bfd99a1c58306d79f
[  190.272011] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.16.0-0-gd239552c-rebuilt.opensuse.org 04/01/2014
[  190.272015] RIP: 0010:rb_check_pages.isra.0+0x6a/0xa0
[  190.272023] Code: [...]
[  190.272028] RSP: 0018:ffff9c37463abb70 EFLAGS: 00010206
[  190.272034] RAX: ffff8eba04b6cb80 RBX: 0000000000000007 RCX: ffff8eba01f13d80
[  190.272038] RDX: ffff8eba01f130c0 RSI: ffff8eba04b6cd00 RDI: ffff8eba0004c700
[  190.272042] RBP: ffff8eba0004c700 R08: 0000000000010002 R09: 0000000000000000
[  190.272045] R10: 00000000ffff7f52 R11: ffff8eba7f600000 R12: ffff8eba0004c720
[  190.272049] R13: ffff8eba00223a00 R14: 0000000000000008 R15: ffff8eba067a8000
[  190.272053] FS:  00007f1bd64752c0(0000) GS:ffff8eba7f680000(0000) knlGS:0000000000000000
[  190.272057] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  190.272061] CR2: 00007f1bd6662590 CR3: 000000010291e001 CR4: 0000000000370ef0
[  190.272070] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[  190.272073] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[  190.272077] Call Trace:
[  190.272098]  <TASK>
[  190.272189]  ring_buffer_resize+0x2ab/0x460
[  190.272199]  __tracing_resize_ring_buffer.part.0+0x23/0xa0
[  190.272206]  tracing_resize_ring_buffer+0x65/0x90
[  190.272216]  tracing_entries_write+0x74/0xc0
[  190.272225]  vfs_write+0xf5/0x420
[  190.272248]  ksys_write+0x67/0xe0
[  190.272256]  do_syscall_64+0x82/0x170
[  190.272363]  entry_SYSCALL_64_after_hwframe+0x76/0x7e
[  190.272373] RIP: 0033:0x7f1bd657d263
[  190.272381] Code: [...]
[  190.272385] RSP: 002b:00007ffe72b643f8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
[  190.272391] RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 00007f1bd657d263
[  190.272395] RDX: 0000000000000002 RSI: 0000555a6eb538e0 RDI: 0000000000000001
[  190.272398] RBP: 0000555a6eb538e0 R08: 000000000000000a R09: 0000000000000000
[  190.272401] R10: 0000555a6eb55190 R11: 0000000000000246 R12: 00007f1bd6662500
[  190.272404] R13: 0000000000000002 R14: 00007f1bd6667c00 R15: 0000000000000002
[  190.272412]  </TASK>
[  190.272414] ---[ end trace 0000000000000000 ]---

Note that ring_buffer_resize() calls rb_check_pages() only if the parent
trace_buffer has recording disabled. Recent commit d78ab79
("tracing: Stop current tracer when resizing buffer") causes that it is
now always the case which makes it more likely to experience this issue.

The window to hit this race is nonetheless very small. To help
reproducing it, one can add a delay loop in rb_get_reader_page():

 ret = rb_head_page_replace(reader, cpu_buffer->reader_page);
 if (!ret)
 	goto spin;
 for (unsigned i = 0; i < 1U << 26; i++)  /* inserted delay loop */
 	__asm__ __volatile__ ("" : : : "memory");
 rb_list_head(reader->list.next)->prev = &cpu_buffer->reader_page->list;

.. and then run the following commands on the target system:

 echo 1 > /sys/kernel/tracing/events/sched/sched_switch/enable
 while true; do
 	echo 16 > /sys/kernel/tracing/buffer_size_kb; sleep 0.1
 	echo 8 > /sys/kernel/tracing/buffer_size_kb; sleep 0.1
 done &
 while true; do
 	for i in /sys/kernel/tracing/per_cpu/*; do
 		timeout 0.1 cat $i/trace_pipe; sleep 0.2
 	done
 done

To fix the problem, make sure ring_buffer_resize() doesn't invoke
rb_check_pages() concurrently with a reader operating on the same
ring_buffer_per_cpu by taking its cpu_buffer->reader_lock.

Link: https://lore.kernel.org/linux-trace-kernel/20240517134008.24529-3-petr.pavlu@suse.com

Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Fixes: 659f451 ("ring-buffer: Add integrity check at end of iter read")
Signed-off-by: Petr Pavlu <petr.pavlu@suse.com>
[ Fixed whitespace ]
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
amboar pushed a commit that referenced this pull request Jun 13, 2024
[ Upstream commit 88ce010 ]

The session has a header in it which contains a perf env with
bpf_progs. The bpf_progs are accessed by the sideband thread and so
the sideband thread must be stopped before the session is deleted, to
avoid a use after free.  This error was detected by AddressSanitizer
in the following:

  ==2054673==ERROR: AddressSanitizer: heap-use-after-free on address 0x61d000161e00 at pc 0x55769289de54 bp 0x7f9df36d4ab0 sp 0x7f9df36d4aa8
  READ of size 8 at 0x61d000161e00 thread T1
      #0 0x55769289de53 in __perf_env__insert_bpf_prog_info util/env.c:42
      #1 0x55769289dbb1 in perf_env__insert_bpf_prog_info util/env.c:29
      #2 0x557692bbae29 in perf_env__add_bpf_info util/bpf-event.c:483
      #3 0x557692bbb01a in bpf_event__sb_cb util/bpf-event.c:512
      #4 0x5576928b75f4 in perf_evlist__poll_thread util/sideband_evlist.c:68
      #5 0x7f9df96a63eb in start_thread nptl/pthread_create.c:444
      #6 0x7f9df9726a4b in clone3 ../sysdeps/unix/sysv/linux/x86_64/clone3.S:81

  0x61d000161e00 is located 384 bytes inside of 2136-byte region [0x61d000161c80,0x61d0001624d8)
  freed by thread T0 here:
      #0 0x7f9dfa6d7288 in __interceptor_free libsanitizer/asan/asan_malloc_linux.cpp:52
      #1 0x557692978d50 in perf_session__delete util/session.c:319
      #2 0x557692673959 in __cmd_record tools/perf/builtin-record.c:2884
      #3 0x55769267a9f0 in cmd_record tools/perf/builtin-record.c:4259
      #4 0x55769286710c in run_builtin tools/perf/perf.c:349
      #5 0x557692867678 in handle_internal_command tools/perf/perf.c:402
      #6 0x557692867a40 in run_argv tools/perf/perf.c:446
      #7 0x557692867fae in main tools/perf/perf.c:562
      #8 0x7f9df96456c9 in __libc_start_call_main ../sysdeps/nptl/libc_start_call_main.h:58

Fixes: 657ee55 ("perf evlist: Introduce side band thread")
Signed-off-by: Ian Rogers <irogers@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Disha Goel <disgoel@linux.ibm.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Clark <james.clark@arm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kajol Jain <kjain@linux.ibm.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: K Prateek Nayak <kprateek.nayak@amd.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Song Liu <songliubraving@fb.com>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Yicong Yang <yangyicong@hisilicon.com>
Link: https://lore.kernel.org/r/20240301074639.2260708-1-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
amboar pushed a commit that referenced this pull request Jun 13, 2024
[ Upstream commit 769e6a1 ]

ui_browser__show() is capturing the input title that is stack allocated
memory in hist_browser__run().

Avoid a use after return by strdup-ing the string.

Committer notes:

Further explanation from Ian Rogers:

My command line using tui is:
$ sudo bash -c 'rm /tmp/asan.log*; export
ASAN_OPTIONS="log_path=/tmp/asan.log"; /tmp/perf/perf mem record -a
sleep 1; /tmp/perf/perf mem report'
I then go to the perf annotate view and quit. This triggers the asan
error (from the log file):
```
==1254591==ERROR: AddressSanitizer: stack-use-after-return on address
0x7f2813331920 at pc 0x7f28180
65991 bp 0x7fff0a21c750 sp 0x7fff0a21bf10
READ of size 80 at 0x7f2813331920 thread T0
    #0 0x7f2818065990 in __interceptor_strlen
../../../../src/libsanitizer/sanitizer_common/sanitizer_common_interceptors.inc:461
    #1 0x7f2817698251 in SLsmg_write_wrapped_string
(/lib/x86_64-linux-gnu/libslang.so.2+0x98251)
    #2 0x7f28176984b9 in SLsmg_write_nstring
(/lib/x86_64-linux-gnu/libslang.so.2+0x984b9)
    #3 0x55c94045b365 in ui_browser__write_nstring ui/browser.c:60
    #4 0x55c94045c558 in __ui_browser__show_title ui/browser.c:266
    #5 0x55c94045c776 in ui_browser__show ui/browser.c:288
    #6 0x55c94045c06d in ui_browser__handle_resize ui/browser.c:206
    #7 0x55c94047979b in do_annotate ui/browsers/hists.c:2458
    #8 0x55c94047fb17 in evsel__hists_browse ui/browsers/hists.c:3412
    #9 0x55c940480a0c in perf_evsel_menu__run ui/browsers/hists.c:3527
    #10 0x55c940481108 in __evlist__tui_browse_hists ui/browsers/hists.c:3613
    #11 0x55c9404813f7 in evlist__tui_browse_hists ui/browsers/hists.c:3661
    #12 0x55c93ffa253f in report__browse_hists tools/perf/builtin-report.c:671
    #13 0x55c93ffa58ca in __cmd_report tools/perf/builtin-report.c:1141
    #14 0x55c93ffaf159 in cmd_report tools/perf/builtin-report.c:1805
    #15 0x55c94000c05c in report_events tools/perf/builtin-mem.c:374
    #16 0x55c94000d96d in cmd_mem tools/perf/builtin-mem.c:516
    #17 0x55c9400e44ee in run_builtin tools/perf/perf.c:350
    #18 0x55c9400e4a5a in handle_internal_command tools/perf/perf.c:403
    #19 0x55c9400e4e22 in run_argv tools/perf/perf.c:447
    #20 0x55c9400e53ad in main tools/perf/perf.c:561
    #21 0x7f28170456c9 in __libc_start_call_main
../sysdeps/nptl/libc_start_call_main.h:58
    #22 0x7f2817045784 in __libc_start_main_impl ../csu/libc-start.c:360
    #23 0x55c93ff544c0 in _start (/tmp/perf/perf+0x19a4c0) (BuildId:
84899b0e8c7d3a3eaa67b2eb35e3d8b2f8cd4c93)

Address 0x7f2813331920 is located in stack of thread T0 at offset 32 in frame
    #0 0x55c94046e85e in hist_browser__run ui/browsers/hists.c:746

  This frame has 1 object(s):
    [32, 192) 'title' (line 747) <== Memory access at offset 32 is
inside this variable
HINT: this may be a false positive if your program uses some custom
stack unwind mechanism, swapcontext or vfork
```
hist_browser__run isn't on the stack so the asan error looks legit.
There's no clean init/exit on struct ui_browser so I may be trading a
use-after-return for a memory leak, but that seems look a good trade
anyway.

Fixes: 05e8b08 ("perf ui browser: Stop using 'self'")
Signed-off-by: Ian Rogers <irogers@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
Cc: Ben Gainey <ben.gainey@arm.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Clark <james.clark@arm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kajol Jain <kjain@linux.ibm.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: K Prateek Nayak <kprateek.nayak@amd.com>
Cc: Li Dong <lidong@vivo.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Oliver Upton <oliver.upton@linux.dev>
Cc: Paran Lee <p4ranlee@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@amd.com>
Cc: Sun Haiyong <sunhaiyong@loongson.cn>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Yanteng Si <siyanteng@loongson.cn>
Cc: Yicong Yang <yangyicong@hisilicon.com>
Link: https://lore.kernel.org/r/20240507183545.1236093-2-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
amboar pushed a commit that referenced this pull request Jun 17, 2024
commit 9d274c1 upstream.

We have been seeing crashes on duplicate keys in
btrfs_set_item_key_safe():

  BTRFS critical (device vdb): slot 4 key (450 108 8192) new key (450 108 8192)
  ------------[ cut here ]------------
  kernel BUG at fs/btrfs/ctree.c:2620!
  invalid opcode: 0000 [#1] PREEMPT SMP PTI
  CPU: 0 PID: 3139 Comm: xfs_io Kdump: loaded Not tainted 6.9.0 #6
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-2.fc40 04/01/2014
  RIP: 0010:btrfs_set_item_key_safe+0x11f/0x290 [btrfs]

With the following stack trace:

  #0  btrfs_set_item_key_safe (fs/btrfs/ctree.c:2620:4)
  #1  btrfs_drop_extents (fs/btrfs/file.c:411:4)
  #2  log_one_extent (fs/btrfs/tree-log.c:4732:9)
  #3  btrfs_log_changed_extents (fs/btrfs/tree-log.c:4955:9)
  #4  btrfs_log_inode (fs/btrfs/tree-log.c:6626:9)
  #5  btrfs_log_inode_parent (fs/btrfs/tree-log.c:7070:8)
  #6  btrfs_log_dentry_safe (fs/btrfs/tree-log.c:7171:8)
  #7  btrfs_sync_file (fs/btrfs/file.c:1933:8)
  #8  vfs_fsync_range (fs/sync.c:188:9)
  #9  vfs_fsync (fs/sync.c:202:9)
  #10 do_fsync (fs/sync.c:212:9)
  #11 __do_sys_fdatasync (fs/sync.c:225:9)
  #12 __se_sys_fdatasync (fs/sync.c:223:1)
  #13 __x64_sys_fdatasync (fs/sync.c:223:1)
  #14 do_syscall_x64 (arch/x86/entry/common.c:52:14)
  #15 do_syscall_64 (arch/x86/entry/common.c:83:7)
  #16 entry_SYSCALL_64+0xaf/0x14c (arch/x86/entry/entry_64.S:121)

So we're logging a changed extent from fsync, which is splitting an
extent in the log tree. But this split part already exists in the tree,
triggering the BUG().

This is the state of the log tree at the time of the crash, dumped with
drgn (https://github.com/osandov/drgn/blob/main/contrib/btrfs_tree.py)
to get more details than btrfs_print_leaf() gives us:

  >>> print_extent_buffer(prog.crashed_thread().stack_trace()[0]["eb"])
  leaf 33439744 level 0 items 72 generation 9 owner 18446744073709551610
  leaf 33439744 flags 0x100000000000000
  fs uuid e5bd3946-400c-4223-8923-190ef1f18677
  chunk uuid d58cb17e-6d02-494a-829a-18b7d8a399da
          item 0 key (450 INODE_ITEM 0) itemoff 16123 itemsize 160
                  generation 7 transid 9 size 8192 nbytes 8473563889606862198
                  block group 0 mode 100600 links 1 uid 0 gid 0 rdev 0
                  sequence 204 flags 0x10(PREALLOC)
                  atime 1716417703.220000000 (2024-05-22 15:41:43)
                  ctime 1716417704.983333333 (2024-05-22 15:41:44)
                  mtime 1716417704.983333333 (2024-05-22 15:41:44)
                  otime 17592186044416.000000000 (559444-03-08 01:40:16)
          item 1 key (450 INODE_REF 256) itemoff 16110 itemsize 13
                  index 195 namelen 3 name: 193
          item 2 key (450 XATTR_ITEM 1640047104) itemoff 16073 itemsize 37
                  location key (0 UNKNOWN.0 0) type XATTR
                  transid 7 data_len 1 name_len 6
                  name: user.a
                  data a
          item 3 key (450 EXTENT_DATA 0) itemoff 16020 itemsize 53
                  generation 9 type 1 (regular)
                  extent data disk byte 303144960 nr 12288
                  extent data offset 0 nr 4096 ram 12288
                  extent compression 0 (none)
          item 4 key (450 EXTENT_DATA 4096) itemoff 15967 itemsize 53
                  generation 9 type 2 (prealloc)
                  prealloc data disk byte 303144960 nr 12288
                  prealloc data offset 4096 nr 8192
          item 5 key (450 EXTENT_DATA 8192) itemoff 15914 itemsize 53
                  generation 9 type 2 (prealloc)
                  prealloc data disk byte 303144960 nr 12288
                  prealloc data offset 8192 nr 4096
  ...

So the real problem happened earlier: notice that items 4 (4k-12k) and 5
(8k-12k) overlap. Both are prealloc extents. Item 4 straddles i_size and
item 5 starts at i_size.

Here is the state of the filesystem tree at the time of the crash:

  >>> root = prog.crashed_thread().stack_trace()[2]["inode"].root
  >>> ret, nodes, slots = btrfs_search_slot(root, BtrfsKey(450, 0, 0))
  >>> print_extent_buffer(nodes[0])
  leaf 30425088 level 0 items 184 generation 9 owner 5
  leaf 30425088 flags 0x100000000000000
  fs uuid e5bd3946-400c-4223-8923-190ef1f18677
  chunk uuid d58cb17e-6d02-494a-829a-18b7d8a399da
  	...
          item 179 key (450 INODE_ITEM 0) itemoff 4907 itemsize 160
                  generation 7 transid 7 size 4096 nbytes 12288
                  block group 0 mode 100600 links 1 uid 0 gid 0 rdev 0
                  sequence 6 flags 0x10(PREALLOC)
                  atime 1716417703.220000000 (2024-05-22 15:41:43)
                  ctime 1716417703.220000000 (2024-05-22 15:41:43)
                  mtime 1716417703.220000000 (2024-05-22 15:41:43)
                  otime 1716417703.220000000 (2024-05-22 15:41:43)
          item 180 key (450 INODE_REF 256) itemoff 4894 itemsize 13
                  index 195 namelen 3 name: 193
          item 181 key (450 XATTR_ITEM 1640047104) itemoff 4857 itemsize 37
                  location key (0 UNKNOWN.0 0) type XATTR
                  transid 7 data_len 1 name_len 6
                  name: user.a
                  data a
          item 182 key (450 EXTENT_DATA 0) itemoff 4804 itemsize 53
                  generation 9 type 1 (regular)
                  extent data disk byte 303144960 nr 12288
                  extent data offset 0 nr 8192 ram 12288
                  extent compression 0 (none)
          item 183 key (450 EXTENT_DATA 8192) itemoff 4751 itemsize 53
                  generation 9 type 2 (prealloc)
                  prealloc data disk byte 303144960 nr 12288
                  prealloc data offset 8192 nr 4096

Item 5 in the log tree corresponds to item 183 in the filesystem tree,
but nothing matches item 4. Furthermore, item 183 is the last item in
the leaf.

btrfs_log_prealloc_extents() is responsible for logging prealloc extents
beyond i_size. It first truncates any previously logged prealloc extents
that start beyond i_size. Then, it walks the filesystem tree and copies
the prealloc extent items to the log tree.

If it hits the end of a leaf, then it calls btrfs_next_leaf(), which
unlocks the tree and does another search. However, while the filesystem
tree is unlocked, an ordered extent completion may modify the tree. In
particular, it may insert an extent item that overlaps with an extent
item that was already copied to the log tree.

This may manifest in several ways depending on the exact scenario,
including an EEXIST error that is silently translated to a full sync,
overlapping items in the log tree, or this crash. This particular crash
is triggered by the following sequence of events:

- Initially, the file has i_size=4k, a regular extent from 0-4k, and a
  prealloc extent beyond i_size from 4k-12k. The prealloc extent item is
  the last item in its B-tree leaf.
- The file is fsync'd, which copies its inode item and both extent items
  to the log tree.
- An xattr is set on the file, which sets the
  BTRFS_INODE_COPY_EVERYTHING flag.
- The range 4k-8k in the file is written using direct I/O. i_size is
  extended to 8k, but the ordered extent is still in flight.
- The file is fsync'd. Since BTRFS_INODE_COPY_EVERYTHING is set, this
  calls copy_inode_items_to_log(), which calls
  btrfs_log_prealloc_extents().
- btrfs_log_prealloc_extents() finds the 4k-12k prealloc extent in the
  filesystem tree. Since it starts before i_size, it skips it. Since it
  is the last item in its B-tree leaf, it calls btrfs_next_leaf().
- btrfs_next_leaf() unlocks the path.
- The ordered extent completion runs, which converts the 4k-8k part of
  the prealloc extent to written and inserts the remaining prealloc part
  from 8k-12k.
- btrfs_next_leaf() does a search and finds the new prealloc extent
  8k-12k.
- btrfs_log_prealloc_extents() copies the 8k-12k prealloc extent into
  the log tree. Note that it overlaps with the 4k-12k prealloc extent
  that was copied to the log tree by the first fsync.
- fsync calls btrfs_log_changed_extents(), which tries to log the 4k-8k
  extent that was written.
- This tries to drop the range 4k-8k in the log tree, which requires
  adjusting the start of the 4k-12k prealloc extent in the log tree to
  8k.
- btrfs_set_item_key_safe() sees that there is already an extent
  starting at 8k in the log tree and calls BUG().

Fix this by detecting when we're about to insert an overlapping file
extent item in the log tree and truncating the part that would overlap.

CC: stable@vger.kernel.org # 6.1+
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
amboar pushed a commit that referenced this pull request Jun 24, 2024
commit 22f0081 upstream.

The syzbot fuzzer found that the interrupt-URB completion callback in
the cdc-wdm driver was taking too long, and the driver's immediate
resubmission of interrupt URBs with -EPROTO status combined with the
dummy-hcd emulation to cause a CPU lockup:

cdc_wdm 1-1:1.0: nonzero urb status received: -71
cdc_wdm 1-1:1.0: wdm_int_callback - 0 bytes
watchdog: BUG: soft lockup - CPU#0 stuck for 26s! [syz-executor782:6625]
CPU#0 Utilization every 4s during lockup:
	#1:  98% system,	  0% softirq,	  3% hardirq,	  0% idle
	#2:  98% system,	  0% softirq,	  3% hardirq,	  0% idle
	#3:  98% system,	  0% softirq,	  3% hardirq,	  0% idle
	#4:  98% system,	  0% softirq,	  3% hardirq,	  0% idle
	#5:  98% system,	  1% softirq,	  3% hardirq,	  0% idle
Modules linked in:
irq event stamp: 73096
hardirqs last  enabled at (73095): [<ffff80008037bc00>] console_emit_next_record kernel/printk/printk.c:2935 [inline]
hardirqs last  enabled at (73095): [<ffff80008037bc00>] console_flush_all+0x650/0xb74 kernel/printk/printk.c:2994
hardirqs last disabled at (73096): [<ffff80008af10b00>] __el1_irq arch/arm64/kernel/entry-common.c:533 [inline]
hardirqs last disabled at (73096): [<ffff80008af10b00>] el1_interrupt+0x24/0x68 arch/arm64/kernel/entry-common.c:551
softirqs last  enabled at (73048): [<ffff8000801ea530>] softirq_handle_end kernel/softirq.c:400 [inline]
softirqs last  enabled at (73048): [<ffff8000801ea530>] handle_softirqs+0xa60/0xc34 kernel/softirq.c:582
softirqs last disabled at (73043): [<ffff800080020de8>] __do_softirq+0x14/0x20 kernel/softirq.c:588
CPU: 0 PID: 6625 Comm: syz-executor782 Tainted: G        W          6.10.0-rc2-syzkaller-g8867bbd4a056 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024

Testing showed that the problem did not occur if the two error
messages -- the first two lines above -- were removed; apparently adding
material to the kernel log takes a surprisingly large amount of time.

In any case, the best approach for preventing these lockups and to
avoid spamming the log with thousands of error messages per second is
to ratelimit the two dev_err() calls.  Therefore we replace them with
dev_err_ratelimited().

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Suggested-by: Greg KH <gregkh@linuxfoundation.org>
Reported-and-tested-by: syzbot+5f996b83575ef4058638@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/linux-usb/00000000000073d54b061a6a1c65@google.com/
Reported-and-tested-by: syzbot+1b2abad17596ad03dcff@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/linux-usb/000000000000f45085061aa9b37e@google.com/
Fixes: 9908a32 ("USB: remove err() macro from usb class drivers")
Link: https://lore.kernel.org/linux-usb/40dfa45b-5f21-4eef-a8c1-51a2f320e267@rowland.harvard.edu/
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/29855215-52f5-4385-b058-91f42c2bee18@rowland.harvard.edu
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
amboar pushed a commit that referenced this pull request Jul 10, 2024
…play

[ Upstream commit d182575 ]

During inode logging (and log replay too), we are holding a transaction
handle and we often need to call btrfs_iget(), which will read an inode
from its subvolume btree if it's not loaded in memory and that results in
allocating an inode with GFP_KERNEL semantics at the btrfs_alloc_inode()
callback - and this may recurse into the filesystem in case we are under
memory pressure and attempt to commit the current transaction, resulting
in a deadlock since the logging (or log replay) task is holding a
transaction handle open.

Syzbot reported this with the following stack traces:

  WARNING: possible circular locking dependency detected
  6.10.0-rc2-syzkaller-00361-g061d1af7b030 #0 Not tainted
  ------------------------------------------------------
  syz-executor.1/9919 is trying to acquire lock:
  ffffffff8dd3aac0 (fs_reclaim){+.+.}-{0:0}, at: might_alloc include/linux/sched/mm.h:334 [inline]
  ffffffff8dd3aac0 (fs_reclaim){+.+.}-{0:0}, at: slab_pre_alloc_hook mm/slub.c:3891 [inline]
  ffffffff8dd3aac0 (fs_reclaim){+.+.}-{0:0}, at: slab_alloc_node mm/slub.c:3981 [inline]
  ffffffff8dd3aac0 (fs_reclaim){+.+.}-{0:0}, at: kmem_cache_alloc_lru_noprof+0x58/0x2f0 mm/slub.c:4020

  but task is already holding lock:
  ffff88804b569358 (&ei->log_mutex){+.+.}-{3:3}, at: btrfs_log_inode+0x39c/0x4660 fs/btrfs/tree-log.c:6481

  which lock already depends on the new lock.

  the existing dependency chain (in reverse order) is:

  -> #3 (&ei->log_mutex){+.+.}-{3:3}:
         __mutex_lock_common kernel/locking/mutex.c:608 [inline]
         __mutex_lock+0x175/0x9c0 kernel/locking/mutex.c:752
         btrfs_log_inode+0x39c/0x4660 fs/btrfs/tree-log.c:6481
         btrfs_log_inode_parent+0x8cb/0x2a90 fs/btrfs/tree-log.c:7079
         btrfs_log_dentry_safe+0x59/0x80 fs/btrfs/tree-log.c:7180
         btrfs_sync_file+0x9c1/0xe10 fs/btrfs/file.c:1959
         vfs_fsync_range+0x141/0x230 fs/sync.c:188
         generic_write_sync include/linux/fs.h:2794 [inline]
         btrfs_do_write_iter+0x584/0x10c0 fs/btrfs/file.c:1705
         new_sync_write fs/read_write.c:497 [inline]
         vfs_write+0x6b6/0x1140 fs/read_write.c:590
         ksys_write+0x12f/0x260 fs/read_write.c:643
         do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline]
         __do_fast_syscall_32+0x73/0x120 arch/x86/entry/common.c:386
         do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411
         entry_SYSENTER_compat_after_hwframe+0x84/0x8e

  -> #2 (btrfs_trans_num_extwriters){++++}-{0:0}:
         join_transaction+0x164/0xf40 fs/btrfs/transaction.c:315
         start_transaction+0x427/0x1a70 fs/btrfs/transaction.c:700
         btrfs_commit_super+0xa1/0x110 fs/btrfs/disk-io.c:4170
         close_ctree+0xcb0/0xf90 fs/btrfs/disk-io.c:4324
         generic_shutdown_super+0x159/0x3d0 fs/super.c:642
         kill_anon_super+0x3a/0x60 fs/super.c:1226
         btrfs_kill_super+0x3b/0x50 fs/btrfs/super.c:2096
         deactivate_locked_super+0xbe/0x1a0 fs/super.c:473
         deactivate_super+0xde/0x100 fs/super.c:506
         cleanup_mnt+0x222/0x450 fs/namespace.c:1267
         task_work_run+0x14e/0x250 kernel/task_work.c:180
         resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
         exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
         exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
         __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
         syscall_exit_to_user_mode+0x278/0x2a0 kernel/entry/common.c:218
         __do_fast_syscall_32+0x80/0x120 arch/x86/entry/common.c:389
         do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411
         entry_SYSENTER_compat_after_hwframe+0x84/0x8e

  -> #1 (btrfs_trans_num_writers){++++}-{0:0}:
         __lock_release kernel/locking/lockdep.c:5468 [inline]
         lock_release+0x33e/0x6c0 kernel/locking/lockdep.c:5774
         percpu_up_read include/linux/percpu-rwsem.h:99 [inline]
         __sb_end_write include/linux/fs.h:1650 [inline]
         sb_end_intwrite include/linux/fs.h:1767 [inline]
         __btrfs_end_transaction+0x5ca/0x920 fs/btrfs/transaction.c:1071
         btrfs_commit_inode_delayed_inode+0x228/0x330 fs/btrfs/delayed-inode.c:1301
         btrfs_evict_inode+0x960/0xe80 fs/btrfs/inode.c:5291
         evict+0x2ed/0x6c0 fs/inode.c:667
         iput_final fs/inode.c:1741 [inline]
         iput.part.0+0x5a8/0x7f0 fs/inode.c:1767
         iput+0x5c/0x80 fs/inode.c:1757
         dentry_unlink_inode+0x295/0x480 fs/dcache.c:400
         __dentry_kill+0x1d0/0x600 fs/dcache.c:603
         dput.part.0+0x4b1/0x9b0 fs/dcache.c:845
         dput+0x1f/0x30 fs/dcache.c:835
         ovl_stack_put+0x60/0x90 fs/overlayfs/util.c:132
         ovl_destroy_inode+0xc6/0x190 fs/overlayfs/super.c:182
         destroy_inode+0xc4/0x1b0 fs/inode.c:311
         iput_final fs/inode.c:1741 [inline]
         iput.part.0+0x5a8/0x7f0 fs/inode.c:1767
         iput+0x5c/0x80 fs/inode.c:1757
         dentry_unlink_inode+0x295/0x480 fs/dcache.c:400
         __dentry_kill+0x1d0/0x600 fs/dcache.c:603
         shrink_kill fs/dcache.c:1048 [inline]
         shrink_dentry_list+0x140/0x5d0 fs/dcache.c:1075
         prune_dcache_sb+0xeb/0x150 fs/dcache.c:1156
         super_cache_scan+0x32a/0x550 fs/super.c:221
         do_shrink_slab+0x44f/0x11c0 mm/shrinker.c:435
         shrink_slab_memcg mm/shrinker.c:548 [inline]
         shrink_slab+0xa87/0x1310 mm/shrinker.c:626
         shrink_one+0x493/0x7c0 mm/vmscan.c:4790
         shrink_many mm/vmscan.c:4851 [inline]
         lru_gen_shrink_node+0x89f/0x1750 mm/vmscan.c:4951
         shrink_node mm/vmscan.c:5910 [inline]
         kswapd_shrink_node mm/vmscan.c:6720 [inline]
         balance_pgdat+0x1105/0x1970 mm/vmscan.c:6911
         kswapd+0x5ea/0xbf0 mm/vmscan.c:7180
         kthread+0x2c1/0x3a0 kernel/kthread.c:389
         ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
         ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

  -> #0 (fs_reclaim){+.+.}-{0:0}:
         check_prev_add kernel/locking/lockdep.c:3134 [inline]
         check_prevs_add kernel/locking/lockdep.c:3253 [inline]
         validate_chain kernel/locking/lockdep.c:3869 [inline]
         __lock_acquire+0x2478/0x3b30 kernel/locking/lockdep.c:5137
         lock_acquire kernel/locking/lockdep.c:5754 [inline]
         lock_acquire+0x1b1/0x560 kernel/locking/lockdep.c:5719
         __fs_reclaim_acquire mm/page_alloc.c:3801 [inline]
         fs_reclaim_acquire+0x102/0x160 mm/page_alloc.c:3815
         might_alloc include/linux/sched/mm.h:334 [inline]
         slab_pre_alloc_hook mm/slub.c:3891 [inline]
         slab_alloc_node mm/slub.c:3981 [inline]
         kmem_cache_alloc_lru_noprof+0x58/0x2f0 mm/slub.c:4020
         btrfs_alloc_inode+0x118/0xb20 fs/btrfs/inode.c:8411
         alloc_inode+0x5d/0x230 fs/inode.c:261
         iget5_locked fs/inode.c:1235 [inline]
         iget5_locked+0x1c9/0x2c0 fs/inode.c:1228
         btrfs_iget_locked fs/btrfs/inode.c:5590 [inline]
         btrfs_iget_path fs/btrfs/inode.c:5607 [inline]
         btrfs_iget+0xfb/0x230 fs/btrfs/inode.c:5636
         add_conflicting_inode fs/btrfs/tree-log.c:5657 [inline]
         copy_inode_items_to_log+0x1039/0x1e30 fs/btrfs/tree-log.c:5928
         btrfs_log_inode+0xa48/0x4660 fs/btrfs/tree-log.c:6592
         log_new_delayed_dentries fs/btrfs/tree-log.c:6363 [inline]
         btrfs_log_inode+0x27dd/0x4660 fs/btrfs/tree-log.c:6718
         btrfs_log_all_parents fs/btrfs/tree-log.c:6833 [inline]
         btrfs_log_inode_parent+0x22ba/0x2a90 fs/btrfs/tree-log.c:7141
         btrfs_log_dentry_safe+0x59/0x80 fs/btrfs/tree-log.c:7180
         btrfs_sync_file+0x9c1/0xe10 fs/btrfs/file.c:1959
         vfs_fsync_range+0x141/0x230 fs/sync.c:188
         generic_write_sync include/linux/fs.h:2794 [inline]
         btrfs_do_write_iter+0x584/0x10c0 fs/btrfs/file.c:1705
         do_iter_readv_writev+0x504/0x780 fs/read_write.c:741
         vfs_writev+0x36f/0xde0 fs/read_write.c:971
         do_pwritev+0x1b2/0x260 fs/read_write.c:1072
         __do_compat_sys_pwritev2 fs/read_write.c:1218 [inline]
         __se_compat_sys_pwritev2 fs/read_write.c:1210 [inline]
         __ia32_compat_sys_pwritev2+0x121/0x1b0 fs/read_write.c:1210
         do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline]
         __do_fast_syscall_32+0x73/0x120 arch/x86/entry/common.c:386
         do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411
         entry_SYSENTER_compat_after_hwframe+0x84/0x8e

  other info that might help us debug this:

  Chain exists of:
    fs_reclaim --> btrfs_trans_num_extwriters --> &ei->log_mutex

   Possible unsafe locking scenario:

         CPU0                    CPU1
         ----                    ----
    lock(&ei->log_mutex);
                                 lock(btrfs_trans_num_extwriters);
                                 lock(&ei->log_mutex);
    lock(fs_reclaim);

   *** DEADLOCK ***

  7 locks held by syz-executor.1/9919:
   #0: ffff88802be20420 (sb_writers#23){.+.+}-{0:0}, at: do_pwritev+0x1b2/0x260 fs/read_write.c:1072
   #1: ffff888065c0f8f0 (&sb->s_type->i_mutex_key#33){++++}-{3:3}, at: inode_lock include/linux/fs.h:791 [inline]
   #1: ffff888065c0f8f0 (&sb->s_type->i_mutex_key#33){++++}-{3:3}, at: btrfs_inode_lock+0xc8/0x110 fs/btrfs/inode.c:385
   #2: ffff888065c0f778 (&ei->i_mmap_lock){++++}-{3:3}, at: btrfs_inode_lock+0xee/0x110 fs/btrfs/inode.c:388
   #3: ffff88802be20610 (sb_internal#4){.+.+}-{0:0}, at: btrfs_sync_file+0x95b/0xe10 fs/btrfs/file.c:1952
   #4: ffff8880546323f0 (btrfs_trans_num_writers){++++}-{0:0}, at: join_transaction+0x430/0xf40 fs/btrfs/transaction.c:290
   #5: ffff888054632418 (btrfs_trans_num_extwriters){++++}-{0:0}, at: join_transaction+0x430/0xf40 fs/btrfs/transaction.c:290
   #6: ffff88804b569358 (&ei->log_mutex){+.+.}-{3:3}, at: btrfs_log_inode+0x39c/0x4660 fs/btrfs/tree-log.c:6481

  stack backtrace:
  CPU: 2 PID: 9919 Comm: syz-executor.1 Not tainted 6.10.0-rc2-syzkaller-00361-g061d1af7b030 #0
  Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
  Call Trace:
   <TASK>
   __dump_stack lib/dump_stack.c:88 [inline]
   dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:114
   check_noncircular+0x31a/0x400 kernel/locking/lockdep.c:2187
   check_prev_add kernel/locking/lockdep.c:3134 [inline]
   check_prevs_add kernel/locking/lockdep.c:3253 [inline]
   validate_chain kernel/locking/lockdep.c:3869 [inline]
   __lock_acquire+0x2478/0x3b30 kernel/locking/lockdep.c:5137
   lock_acquire kernel/locking/lockdep.c:5754 [inline]
   lock_acquire+0x1b1/0x560 kernel/locking/lockdep.c:5719
   __fs_reclaim_acquire mm/page_alloc.c:3801 [inline]
   fs_reclaim_acquire+0x102/0x160 mm/page_alloc.c:3815
   might_alloc include/linux/sched/mm.h:334 [inline]
   slab_pre_alloc_hook mm/slub.c:3891 [inline]
   slab_alloc_node mm/slub.c:3981 [inline]
   kmem_cache_alloc_lru_noprof+0x58/0x2f0 mm/slub.c:4020
   btrfs_alloc_inode+0x118/0xb20 fs/btrfs/inode.c:8411
   alloc_inode+0x5d/0x230 fs/inode.c:261
   iget5_locked fs/inode.c:1235 [inline]
   iget5_locked+0x1c9/0x2c0 fs/inode.c:1228
   btrfs_iget_locked fs/btrfs/inode.c:5590 [inline]
   btrfs_iget_path fs/btrfs/inode.c:5607 [inline]
   btrfs_iget+0xfb/0x230 fs/btrfs/inode.c:5636
   add_conflicting_inode fs/btrfs/tree-log.c:5657 [inline]
   copy_inode_items_to_log+0x1039/0x1e30 fs/btrfs/tree-log.c:5928
   btrfs_log_inode+0xa48/0x4660 fs/btrfs/tree-log.c:6592
   log_new_delayed_dentries fs/btrfs/tree-log.c:6363 [inline]
   btrfs_log_inode+0x27dd/0x4660 fs/btrfs/tree-log.c:6718
   btrfs_log_all_parents fs/btrfs/tree-log.c:6833 [inline]
   btrfs_log_inode_parent+0x22ba/0x2a90 fs/btrfs/tree-log.c:7141
   btrfs_log_dentry_safe+0x59/0x80 fs/btrfs/tree-log.c:7180
   btrfs_sync_file+0x9c1/0xe10 fs/btrfs/file.c:1959
   vfs_fsync_range+0x141/0x230 fs/sync.c:188
   generic_write_sync include/linux/fs.h:2794 [inline]
   btrfs_do_write_iter+0x584/0x10c0 fs/btrfs/file.c:1705
   do_iter_readv_writev+0x504/0x780 fs/read_write.c:741
   vfs_writev+0x36f/0xde0 fs/read_write.c:971
   do_pwritev+0x1b2/0x260 fs/read_write.c:1072
   __do_compat_sys_pwritev2 fs/read_write.c:1218 [inline]
   __se_compat_sys_pwritev2 fs/read_write.c:1210 [inline]
   __ia32_compat_sys_pwritev2+0x121/0x1b0 fs/read_write.c:1210
   do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline]
   __do_fast_syscall_32+0x73/0x120 arch/x86/entry/common.c:386
   do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411
   entry_SYSENTER_compat_after_hwframe+0x84/0x8e
  RIP: 0023:0xf7334579
  Code: b8 01 10 06 03 (...)
  RSP: 002b:00000000f5f265ac EFLAGS: 00000292 ORIG_RAX: 000000000000017b
  RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 00000000200002c0
  RDX: 0000000000000001 RSI: 0000000000000000 RDI: 0000000000000000
  RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
  R10: 0000000000000000 R11: 0000000000000292 R12: 0000000000000000
  R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000

Fix this by ensuring we are under a NOFS scope whenever we call
btrfs_iget() during inode logging and log replay.

Reported-by: syzbot+8576cfa84070dce4d59b@syzkaller.appspotmail.com
Link: https://lore.kernel.org/linux-btrfs/000000000000274a3a061abbd928@google.com/
Fixes: 712e36c ("btrfs: use GFP_KERNEL in btrfs_alloc_inode")
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
amboar pushed a commit that referenced this pull request Jul 10, 2024
commit be346c1 upstream.

The code in ocfs2_dio_end_io_write() estimates number of necessary
transaction credits using ocfs2_calc_extend_credits().  This however does
not take into account that the IO could be arbitrarily large and can
contain arbitrary number of extents.

Extent tree manipulations do often extend the current transaction but not
in all of the cases.  For example if we have only single block extents in
the tree, ocfs2_mark_extent_written() will end up calling
ocfs2_replace_extent_rec() all the time and we will never extend the
current transaction and eventually exhaust all the transaction credits if
the IO contains many single block extents.  Once that happens a
WARN_ON(jbd2_handle_buffer_credits(handle) <= 0) is triggered in
jbd2_journal_dirty_metadata() and subsequently OCFS2 aborts in response to
this error.  This was actually triggered by one of our customers on a
heavily fragmented OCFS2 filesystem.

To fix the issue make sure the transaction always has enough credits for
one extent insert before each call of ocfs2_mark_extent_written().

Heming Zhao said:

------
PANIC: "Kernel panic - not syncing: OCFS2: (device dm-1): panic forced after error"

PID: xxx  TASK: xxxx  CPU: 5  COMMAND: "SubmitThread-CA"
  #0 machine_kexec at ffffffff8c069932
  #1 __crash_kexec at ffffffff8c1338fa
  #2 panic at ffffffff8c1d69b9
  #3 ocfs2_handle_error at ffffffffc0c86c0c [ocfs2]
  #4 __ocfs2_abort at ffffffffc0c88387 [ocfs2]
  #5 ocfs2_journal_dirty at ffffffffc0c51e98 [ocfs2]
  #6 ocfs2_split_extent at ffffffffc0c27ea3 [ocfs2]
  #7 ocfs2_change_extent_flag at ffffffffc0c28053 [ocfs2]
  #8 ocfs2_mark_extent_written at ffffffffc0c28347 [ocfs2]
  #9 ocfs2_dio_end_io_write at ffffffffc0c2bef9 [ocfs2]
#10 ocfs2_dio_end_io at ffffffffc0c2c0f5 [ocfs2]
#11 dio_complete at ffffffff8c2b9fa7
#12 do_blockdev_direct_IO at ffffffff8c2bc09f
#13 ocfs2_direct_IO at ffffffffc0c2b653 [ocfs2]
#14 generic_file_direct_write at ffffffff8c1dcf14
#15 __generic_file_write_iter at ffffffff8c1dd07b
#16 ocfs2_file_write_iter at ffffffffc0c49f1f [ocfs2]
#17 aio_write at ffffffff8c2cc72e
#18 kmem_cache_alloc at ffffffff8c248dde
#19 do_io_submit at ffffffff8c2ccada
#20 do_syscall_64 at ffffffff8c004984
#21 entry_SYSCALL_64_after_hwframe at ffffffff8c8000ba

Link: https://lkml.kernel.org/r/20240617095543.6971-1-jack@suse.cz
Link: https://lkml.kernel.org/r/20240614145243.8837-1-jack@suse.cz
Fixes: c15471f ("ocfs2: fix sparse file & data ordering issue in direct io")
Signed-off-by: Jan Kara <jack@suse.cz>
Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Reviewed-by: Heming Zhao <heming.zhao@suse.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Changwei Ge <gechangwei@live.cn>
Cc: Gang He <ghe@suse.com>
Cc: Jun Piao <piaojun@huawei.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
amboar pushed a commit that referenced this pull request Jul 12, 2024
[ Upstream commit 3b3b84a ]

As reported by Jose E. Marchesi in off-list discussion, GCC and LLVM
generate slightly different code for dummy_st_ops_success/test_1():

  SEC("struct_ops/test_1")
  int BPF_PROG(test_1, struct bpf_dummy_ops_state *state)
  {
  	int ret;

  	if (!state)
  		return 0xf2f3f4f5;

  	ret = state->val;
  	state->val = 0x5a;
  	return ret;
  }

  GCC-generated                  LLVM-generated
  ----------------------------   ---------------------------
  0: r1 = *(u64 *)(r1 + 0x0)     0: w0 = -0xd0c0b0b
  1: if r1 == 0x0 goto 5f        1: r1 = *(u64 *)(r1 + 0x0)
  2: r0 = *(s32 *)(r1 + 0x0)     2: if r1 == 0x0 goto 6f
  3: *(u32 *)(r1 + 0x0) = 0x5a   3: r0 = *(u32 *)(r1 + 0x0)
  4: exit                        4: w2 = 0x5a
  5: r0 = -0xd0c0b0b             5: *(u32 *)(r1 + 0x0) = r2
  6: exit                        6: exit

If the 'state' argument is not marked as nullable in
net/bpf/bpf_dummy_struct_ops.c, the verifier would assume that
'r1 == 0x0' is never true:
- for the GCC version, this means that instructions #5-6 would be
  marked as dead and removed;
- for the LLVM version, all instructions would be marked as live.

The test dummy_st_ops/dummy_init_ret_value actually sets the 'state'
parameter to NULL.

Therefore, when the 'state' argument is not marked as nullable,
the GCC-generated version of the code would trigger a NULL pointer
dereference at instruction #3.

This patch updates the test_1() test case to always follow a shape
similar to the GCC-generated version above, in order to verify whether
the 'state' nullability is marked correctly.

Reported-by: Jose E. Marchesi <jemarch@gnu.org>
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20240424012821.595216-3-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
amboar pushed a commit that referenced this pull request Jul 12, 2024
… __netif_rx()

[ Upstream commit e15a5d8 ]

The following is emitted when using idxd (DSA) dmanegine as the data
mover for ntb_transport that ntb_netdev uses.

[74412.546922] BUG: using smp_processor_id() in preemptible [00000000] code: irq/52-idxd-por/14526
[74412.556784] caller is netif_rx_internal+0x42/0x130
[74412.562282] CPU: 6 PID: 14526 Comm: irq/52-idxd-por Not tainted 6.9.5 #5
[74412.569870] Hardware name: Intel Corporation ArcherCity/ArcherCity, BIOS EGSDCRB1.E9I.1752.P05.2402080856 02/08/2024
[74412.581699] Call Trace:
[74412.584514]  <TASK>
[74412.586933]  dump_stack_lvl+0x55/0x70
[74412.591129]  check_preemption_disabled+0xc8/0xf0
[74412.596374]  netif_rx_internal+0x42/0x130
[74412.600957]  __netif_rx+0x20/0xd0
[74412.604743]  ntb_netdev_rx_handler+0x66/0x150 [ntb_netdev]
[74412.610985]  ntb_complete_rxc+0xed/0x140 [ntb_transport]
[74412.617010]  ntb_rx_copy_callback+0x53/0x80 [ntb_transport]
[74412.623332]  idxd_dma_complete_txd+0xe3/0x160 [idxd]
[74412.628963]  idxd_wq_thread+0x1a6/0x2b0 [idxd]
[74412.634046]  irq_thread_fn+0x21/0x60
[74412.638134]  ? irq_thread+0xa8/0x290
[74412.642218]  irq_thread+0x1a0/0x290
[74412.646212]  ? __pfx_irq_thread_fn+0x10/0x10
[74412.651071]  ? __pfx_irq_thread_dtor+0x10/0x10
[74412.656117]  ? __pfx_irq_thread+0x10/0x10
[74412.660686]  kthread+0x100/0x130
[74412.664384]  ? __pfx_kthread+0x10/0x10
[74412.668639]  ret_from_fork+0x31/0x50
[74412.672716]  ? __pfx_kthread+0x10/0x10
[74412.676978]  ret_from_fork_asm+0x1a/0x30
[74412.681457]  </TASK>

The cause is due to the idxd driver interrupt completion handler uses
threaded interrupt and the threaded handler is not hard or soft interrupt
context. However __netif_rx() can only be called from interrupt context.
Change the call to netif_rx() in order to allow completion via normal
context for dmaengine drivers that utilize threaded irq handling.

While the following commit changed from netif_rx() to __netif_rx(),
baebdf4 ("net: dev: Makes sure netif_rx() can be invoked in any context."),
the change should've been a noop instead. However, the code precedes this
fix should've been using netif_rx_ni() or netif_rx_any_context().

Fixes: 548c237 ("net: Add support for NTB virtual ethernet device")
Reported-by: Jerry Dai <jerry.dai@intel.com>
Tested-by: Jerry Dai <jerry.dai@intel.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Link: https://patch.msgid.link/20240701181538.3799546-1-dave.jiang@intel.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
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