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DRM: totally broken VOP output mode selector rk3288 #10

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mcerveny opened this issue Apr 16, 2017 · 11 comments
Closed

DRM: totally broken VOP output mode selector rk3288 #10

mcerveny opened this issue Apr 16, 2017 · 11 comments

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@mcerveny
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Hello.

There is totally broken VOP for rk3288 platforms (TinkerBoard, ...). It usually boots only to 800x600 resolution that pass both errors (see also http://tinkerboarding.co.uk/forum/showthread.php?tid=61&pid=323#pid323).
I identified 2 issues in rockchip DRM/kernel but unable to correct:

1) nearly all output modes are blocked for DMT/VESA modes

Problem is in new validity checking (commit 7e3e0c5) and/or modification of "dclk_vop" clock driver (commit d072a98 maybe other). Due to strictly checking available clock in vop_crtc_mode_valid() (see https://github.com/rockchip-linux/kernel/blob/release-4.4/drivers/gpu/drm/rockchip/rockchip_drm_vop.c#L1443) and some modification in "dclk_vop" clock driver it is not possible to set even basic DMT/VESA modes. Mode validation fails with MODE_CLOCK_RANGE. Example (compare clock != request_clock from code):

Modeline 100:"1280x1024" 75 135000 1280 1296 1440 1688 1024 1025 1028 1066 0x40 0x5
clock error: 133333 != 135000
Modeline 80:"1280x1024" 60 108000 1280 1328 1440 1688 1024 1025 1028 1066 0x48 0x5
clock error: 100000 != 108000
Modeline 88:"1024x768" 75 78800 1024 1040 1136 1312 768 769 772 800 0x40 0x5
clock error: 74250 != 78800
Modeline 90:"1024x768" 60 65000 1024 1048 1184 1344 768 771 777 806 0x40 0xa
clock error: 62500 != 65000

2) check modes to "fail-safe" framebuffer size (1024x768) and not to maximum available

The problem is in late hdmi start (state "connected"). Framebuffer is already set do "1024x768" default but new modes are validated to this resolution and not to maximum available (8192x8192?). Mode validation fails with MODE_VIRTUAL_X. Sample from dmesg (XXXX is inside drm_mode_validate_size() "DRM_DEBUG_KMS("XXXX %dx%d %dx%d\n", mode->hdisplay, mode->vdisplay, maxX, maxY);" and "dump_stack()" shows call from drm_fb_helper_hotplug_event() (https://github.com/rockchip-linux/kernel/blob/release-4.4/drivers/gpu/drm/drm_fb_helper.c#L2161) and from rockchip_drm_output_poll_changed() (https://github.com/rockchip-linux/kernel/blob/release-4.4/drivers/gpu/drm/rockchip/rockchip_drm_fb.c#L220)):

[    1.440674] [drm:drm_helper_probe_single_connector_modes_merge_bits] [CONNECTOR:78:HDMI-A-1] disconnected
[    1.440693] rockchip-drm display-subsystem: No connectors reported connected with modes
[    1.448764] [drm:drm_setup_crtcs] 
[    1.448795] [drm:drm_sysfs_hotplug_event] generating hotplug event
[    1.448849] [drm:drm_enable_connectors] connector 78 enabled? no
[    1.448865] [drm:drm_setup_crtcs] picking CRTCs for 8192x8192 config
[    1.448881] [drm:drm_fb_helper_single_fb_probe] Cannot find any crtc or sizes - going 1024x768
[    1.462950] [drm:rockchip_gem_get_pages] rockchip_gem_get_pages, 201, end = 768, n_pages = 768
[    1.467034] [drm:rockchip_drm_fbdev_create] FB [1024x768]-24 kvaddr=f0921000 offset=0 size=3145728
....
[    4.246398] [drm:drm_helper_hpd_irq_event] [CONNECTOR:78:HDMI-A-1] status updated from disconnected to connected
[    4.246411] [drm:drm_sysfs_hotplug_event] generating hotplug event
[    4.246451] [drm:drm_fb_helper_hotplug_event] 
[    4.246467] [drm:drm_helper_probe_single_connector_modes_merge_bits] [CONNECTOR:78:HDMI-A-1]
....
[    4.572432] [drm:drm_mode_validate_size] XXXX 1280x1024 1024x768

Are there any new patches to resolve this issues ?

Thanks, Martin

@wzyy2
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wzyy2 commented Apr 17, 2017

@yueshu

@mcerveny
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mcerveny commented Apr 17, 2017

Tested with release-20170417, not resolved (dmesg with "drm.debug=0x4" on linux cmdline).

[    3.570313] [drm:drm_mode_debug_printmodeline] Modeline 81:"1280x1024" 60 108000 1280 1328 1440 1688 1024 1025 1028 1066 0x48 0x5
[    3.570319] [drm:drm_mode_prune_invalid] Not using 1280x1024 mode: VIRTUAL_X
[    3.570333] [drm:drm_mode_debug_printmodeline] Modeline 83:"640x480" 0 31500 640 656 720 840 480 481 484 500 0x40 0xa
[    3.570339] [drm:drm_mode_prune_invalid] Not using 640x480 mode: CLOCK_RANGE
[    3.570351] [drm:drm_mode_debug_printmodeline] Modeline 84:"640x480" 0 31500 640 664 704 832 480 489 491 520 0x40 0xa
[    3.570357] [drm:drm_mode_prune_invalid] Not using 640x480 mode: CLOCK_RANGE
[    3.570368] [drm:drm_mode_debug_printmodeline] Modeline 85:"640x480" 0 25200 640 656 752 800 480 490 492 525 0x40 0xa
[    3.570374] [drm:drm_mode_prune_invalid] Not using 640x480 mode: CLOCK_RANGE
[    3.570385] [drm:drm_mode_debug_printmodeline] Modeline 86:"720x400" 0 28320 720 738 846 900 400 412 414 449 0x40 0x6
[    3.570390] [drm:drm_mode_prune_invalid] Not using 720x400 mode: CLOCK_RANGE
[    3.570402] [drm:drm_mode_debug_printmodeline] Modeline 87:"1280x1024" 0 135000 1280 1296 1440 1688 1024 1025 1028 1066 0x40 0x5
[    3.570407] [drm:drm_mode_prune_invalid] Not using 1280x1024 mode: VIRTUAL_X
[    3.570418] [drm:drm_mode_debug_printmodeline] Modeline 88:"1024x768" 0 78800 1024 1040 1136 1312 768 769 772 800 0x40 0x5
[    3.570424] [drm:drm_mode_prune_invalid] Not using 1024x768 mode: CLOCK_RANGE
[    3.570435] [drm:drm_mode_debug_printmodeline] Modeline 89:"1024x768" 0 75000 1024 1048 1184 1328 768 771 777 806 0x40 0xa
[    3.570441] [drm:drm_mode_prune_invalid] Not using 1024x768 mode: CLOCK_RANGE
[    3.570452] [drm:drm_mode_debug_printmodeline] Modeline 90:"1024x768" 0 65000 1024 1048 1184 1344 768 771 777 806 0x40 0xa
[    3.570458] [drm:drm_mode_prune_invalid] Not using 1024x768 mode: CLOCK_RANGE
[    3.570469] [drm:drm_mode_debug_printmodeline] Modeline 91:"832x624" 0 57284 832 864 928 1152 624 625 628 667 0x40 0xa
[    3.570474] [drm:drm_mode_prune_invalid] Not using 832x624 mode: CLOCK_RANGE
[    3.570486] [drm:drm_mode_debug_printmodeline] Modeline 94:"1152x864" 0 108000 1152 1216 1344 1600 864 865 868 900 0x40 0x5
[    3.570492] [drm:drm_mode_prune_invalid] Not using 1152x864 mode: VIRTUAL_X
[    3.570502] [drm:drm_helper_probe_single_connector_modes_merge_bits] [CONNECTOR:78:HDMI-A-1] probed modes :
[    3.570513] [drm:drm_mode_debug_printmodeline] Modeline 92:"800x600" 75 49500 800 816 896 1056 600 601 604 625 0x40 0x5
[    3.570524] [drm:drm_mode_debug_printmodeline] Modeline 93:"800x600" 72 50000 800 856 976 1040 600 637 643 666 0x40 0x5
[    3.570535] [drm:drm_mode_debug_printmodeline] Modeline 82:"800x600" 60 40000 800 840 968 1056 600 601 605 628 0x40 0x5
[    3.570552] [drm:drm_setup_crtcs] 
[    3.570560] [drm:drm_enable_connectors] connector 78 enabled? yes
[    3.570567] [drm:drm_target_preferred] looking for cmdline mode on connector 78
[    3.570573] [drm:drm_target_preferred] looking for preferred mode on connector 78 0
[    3.570578] [drm:drm_target_preferred] found mode 800x600

Kwiboo referenced this issue in Kwiboo/linux-rockchip May 2, 2017
mipsxx_pmu_handle_shared_irq() calls irq_work_run() while holding the
pmuint_rwlock for read.  irq_work_run() can, via perf_pending_event(),
call try_to_wake_up() which can try to take rq->lock.

However, perf can also call perf_pmu_enable() (and thus take the
pmuint_rwlock for write) while holding the rq->lock, from
finish_task_switch() via perf_event_context_sched_in().

This leads to an ABBA deadlock:

 PID: 3855   TASK: 8f7ce288  CPU: 2   COMMAND: "process"
  #0 [89c39ac8] __delay at 803b5be4
  #1 [89c39ac8] do_raw_spin_lock at 8008fdcc
  #2 [89c39af8] try_to_wake_up at 8006e47c
  #3 [89c39b38] pollwake at 8018eab0
  #4 [89c39b68] __wake_up_common at 800879f4
  #5 [89c39b98] __wake_up at 800880e4
  #6 [89c39bc8] perf_event_wakeup at 8012109c
  #7 [89c39be8] perf_pending_event at 80121184
  #8 [89c39c08] irq_work_run_list at 801151f0
  #9 [89c39c38] irq_work_run at 80115274
 #10 [89c39c50] mipsxx_pmu_handle_shared_irq at 8002cc7c

 PID: 1481   TASK: 8eaac6a8  CPU: 3   COMMAND: "process"
  #0 [8de7f900] do_raw_write_lock at 800900e0
  #1 [8de7f918] perf_event_context_sched_in at 80122310
  #2 [8de7f938] __perf_event_task_sched_in at 80122608
  #3 [8de7f958] finish_task_switch at 8006b8a4
  #4 [8de7f998] __schedule at 805e4dc4
  #5 [8de7f9f8] schedule at 805e5558
  #6 [8de7fa10] schedule_hrtimeout_range_clock at 805e9984
  #7 [8de7fa70] poll_schedule_timeout at 8018e8f8
  #8 [8de7fa88] do_select at 8018f338
  #9 [8de7fd88] core_sys_select at 8018f5cc
 #10 [8de7fee0] sys_select at 8018f854
 #11 [8de7ff28] syscall_common at 80028fc8

The lock seems to be there to protect the hardware counters so there is
no need to hold it across irq_work_run().

Signed-off-by: Rabin Vincent <rabinv@axis.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
wzyy2 pushed a commit that referenced this issue May 24, 2017
[ Upstream commit 45caeaa ]

As Eric Dumazet pointed out this also needs to be fixed in IPv6.
v2: Contains the IPv6 tcp/Ipv6 dccp patches as well.

We have seen a few incidents lately where a dst_enty has been freed
with a dangling TCP socket reference (sk->sk_dst_cache) pointing to that
dst_entry. If the conditions/timings are right a crash then ensues when the
freed dst_entry is referenced later on. A Common crashing back trace is:

 #8 [] page_fault at ffffffff8163e648
    [exception RIP: __tcp_ack_snd_check+74]
.
.
 #9 [] tcp_rcv_established at ffffffff81580b64
#10 [] tcp_v4_do_rcv at ffffffff8158b54a
#11 [] tcp_v4_rcv at ffffffff8158cd02
#12 [] ip_local_deliver_finish at ffffffff815668f4
#13 [] ip_local_deliver at ffffffff81566bd9
#14 [] ip_rcv_finish at ffffffff8156656d
#15 [] ip_rcv at ffffffff81566f06
#16 [] __netif_receive_skb_core at ffffffff8152b3a2
#17 [] __netif_receive_skb at ffffffff8152b608
#18 [] netif_receive_skb at ffffffff8152b690
#19 [] vmxnet3_rq_rx_complete at ffffffffa015eeaf [vmxnet3]
#20 [] vmxnet3_poll_rx_only at ffffffffa015f32a [vmxnet3]
#21 [] net_rx_action at ffffffff8152bac2
#22 [] __do_softirq at ffffffff81084b4f
#23 [] call_softirq at ffffffff8164845c
#24 [] do_softirq at ffffffff81016fc5
#25 [] irq_exit at ffffffff81084ee5
#26 [] do_IRQ at ffffffff81648ff8

Of course it may happen with other NIC drivers as well.

It's found the freed dst_entry here:

 224 static bool tcp_in_quickack_mode(struct sock *sk)↩
 225 {↩
 226 ▹       const struct inet_connection_sock *icsk = inet_csk(sk);↩
 227 ▹       const struct dst_entry *dst = __sk_dst_get(sk);↩
 228 ↩
 229 ▹       return (dst && dst_metric(dst, RTAX_QUICKACK)) ||↩
 230 ▹       ▹       (icsk->icsk_ack.quick && !icsk->icsk_ack.pingpong);↩
 231 }↩

But there are other backtraces attributed to the same freed dst_entry in
netfilter code as well.

All the vmcores showed 2 significant clues:

- Remote hosts behind the default gateway had always been redirected to a
different gateway. A rtable/dst_entry will be added for that host. Making
more dst_entrys with lower reference counts. Making this more probable.

- All vmcores showed a postitive LockDroppedIcmps value, e.g:

LockDroppedIcmps                  267

A closer look at the tcp_v4_err() handler revealed that do_redirect() will run
regardless of whether user space has the socket locked. This can result in a
race condition where the same dst_entry cached in sk->sk_dst_entry can be
decremented twice for the same socket via:

do_redirect()->__sk_dst_check()-> dst_release().

Which leads to the dst_entry being prematurely freed with another socket
pointing to it via sk->sk_dst_cache and a subsequent crash.

To fix this skip do_redirect() if usespace has the socket locked. Instead let
the redirect take place later when user space does not have the socket
locked.

The dccp/IPv6 code is very similar in this respect, so fixing it there too.

As Eric Garver pointed out the following commit now invalidates routes. Which
can set the dst->obsolete flag so that ipv4_dst_check() returns null and
triggers the dst_release().

Fixes: ceb3320 ("ipv4: Kill routes during PMTU/redirect updates.")
Cc: Eric Garver <egarver@redhat.com>
Cc: Hannes Sowa <hsowa@redhat.com>
Signed-off-by: Jon Maxwell <jmaxwell37@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
wzyy2 pushed a commit that referenced this issue May 24, 2017
commit 4dfce57 upstream.

There have been several reports over the years of NULL pointer
dereferences in xfs_trans_log_inode during xfs_fsr processes,
when the process is doing an fput and tearing down extents
on the temporary inode, something like:

BUG: unable to handle kernel NULL pointer dereference at 0000000000000018
PID: 29439  TASK: ffff880550584fa0  CPU: 6   COMMAND: "xfs_fsr"
    [exception RIP: xfs_trans_log_inode+0x10]
 #9 [ffff8800a57bbbe0] xfs_bunmapi at ffffffffa037398e [xfs]
#10 [ffff8800a57bbce8] xfs_itruncate_extents at ffffffffa0391b29 [xfs]
#11 [ffff8800a57bbd88] xfs_inactive_truncate at ffffffffa0391d0c [xfs]
#12 [ffff8800a57bbdb8] xfs_inactive at ffffffffa0392508 [xfs]
#13 [ffff8800a57bbdd8] xfs_fs_evict_inode at ffffffffa035907e [xfs]
#14 [ffff8800a57bbe00] evict at ffffffff811e1b67
#15 [ffff8800a57bbe28] iput at ffffffff811e23a5
#16 [ffff8800a57bbe58] dentry_kill at ffffffff811dcfc8
#17 [ffff8800a57bbe88] dput at ffffffff811dd06c
#18 [ffff8800a57bbea8] __fput at ffffffff811c823b
#19 [ffff8800a57bbef0] ____fput at ffffffff811c846e
#20 [ffff8800a57bbf00] task_work_run at ffffffff81093b27
#21 [ffff8800a57bbf30] do_notify_resume at ffffffff81013b0c
#22 [ffff8800a57bbf50] int_signal at ffffffff8161405d

As it turns out, this is because the i_itemp pointer, along
with the d_ops pointer, has been overwritten with zeros
when we tear down the extents during truncate.  When the in-core
inode fork on the temporary inode used by xfs_fsr was originally
set up during the extent swap, we mistakenly looked at di_nextents
to determine whether all extents fit inline, but this misses extents
generated by speculative preallocation; we should be using if_bytes
instead.

This mistake corrupts the in-memory inode, and code in
xfs_iext_remove_inline eventually gets bad inputs, causing
it to memmove and memset incorrect ranges; this became apparent
because the two values in ifp->if_u2.if_inline_ext[1] contained
what should have been in d_ops and i_itemp; they were memmoved due
to incorrect array indexing and then the original locations
were zeroed with memset, again due to an array overrun.

Fix this by properly using i_df.if_bytes to determine the number
of extents, not di_nextents.

Thanks to dchinner for looking at this with me and spotting the
root cause.

[nborisov: backported to 4.4]

Cc: stable@vger.kernel.org
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
--
 fs/xfs/xfs_bmap_util.c |    7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)
@mcerveny
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mcerveny commented Jul 7, 2017

Ping.
Do you have patch for that ?
Is anyone working on it ?

@markyzq
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markyzq commented Jul 10, 2017

  1. nearly all output modes are blocked for DMT/VESA modes
    seems rk3288 need a similar modify to commit d072a98, get accurate clock for hdmi.
    commit d072a98 is for rk3368

  2. check modes to "fail-safe" framebuffer size (1024x768) and not to maximum available
    the problem is drm framework limit, when there is no connector plug, drm framework hard code to use 1024x768 framebuffer size.
    drivers/gpu/drm/drm_fb_helper.c
    sizes.fb_width = sizes.surface_width = 1024;
    sizes.fb_height = sizes.surface_height = 768;
    You can custom modify it for you product, or if we can solved issue 1), this problem would disappear.

@mcerveny
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mcerveny commented Jul 10, 2017

I tried this:

diff --git a/drivers/clk/rockchip/clk-rk3288.c b/drivers/clk/rockchip/clk-rk3288.c
index 7ceee5c..47352ef 100644
--- a/drivers/clk/rockchip/clk-rk3288.c
+++ b/drivers/clk/rockchip/clk-rk3288.c
@@ -179,6 +179,7 @@ PNAME(mux_aclk_cpu_src_p)   = { "cpll_aclk_cpu", "gpll_aclk_cpu" };
 PNAME(mux_pll_src_cpll_gpll_p)         = { "cpll", "gpll" };
 PNAME(mux_pll_src_npll_cpll_gpll_p)    = { "npll", "cpll", "gpll" };
 PNAME(mux_pll_src_cpll_gpll_npll_p)    = { "cpll", "gpll", "npll" };
+PNAME(mux_pll_src_dmycpll_dmygpll_npll_p)      = { "dummy_cpll", "dummy_gpll", "npll" };
 PNAME(mux_pll_src_cpll_gpll_usb480m_p) = { "cpll", "gpll", "usbphy480m_src" };
 PNAME(mux_pll_src_cpll_gll_usb_npll_p) = { "cpll", "gpll", "usbphy480m_src", "npll" };
 
@@ -428,7 +429,7 @@ static struct rockchip_clk_branch rk3288_clk_branches[] __initdata = {
                        RK3288_CLKSEL_CON(30), 14, 2, MFLAGS, 8, 5, DFLAGS,
                        RK3288_CLKGATE_CON(3), 4, GFLAGS),
 
-       COMPOSITE(DCLK_VOP0, "dclk_vop0", mux_pll_src_cpll_gpll_npll_p, 0,
+       COMPOSITE(DCLK_VOP0, "dclk_vop0", mux_pll_src_dmycpll_dmygpll_npll_p, CLK_SET_RATE_PARENT,
                        RK3288_CLKSEL_CON(27), 0, 2, MFLAGS, 8, 8, DFLAGS,
                        RK3288_CLKGATE_CON(3), 1, GFLAGS),
        COMPOSITE(DCLK_VOP1, "dclk_vop1", mux_pll_src_cpll_gpll_npll_p, 0,

But kernel crash:

[    3.377843] Unable to handle kernel NULL pointer dereference at virtual address 00000000
...
[    3.377912] PC is at clk_hw_round_rate+0x28/0x54
...
[    3.379627] [<c08bb8cc>] (clk_hw_round_rate) from [<c08c0c5c>] (divider_round_rate+0x280/0x3b0)
[    3.379640] [<c08c0c5c>] (divider_round_rate) from [<c08c0e20>] (clk_divider_round_rate+0x94/0x9c)
[    3.379653] [<c08c0e20>] (clk_divider_round_rate) from [<c08c1d4c>] (clk_composite_determine_rate+0x128/0x1ec)
[    3.379667] [<c08c1d4c>] (clk_composite_determine_rate) from [<c08bb818>] (clk_core_round_rate_nolock+0x58/0xb4)
[    3.379680] [<c08bb818>] (clk_core_round_rate_nolock) from [<c08bdc74>] (clk_round_rate+0x48/0x68)
[    3.379697] [<c08bdc74>] (clk_round_rate) from [<c04d34d0>] (vop_crtc_mode_valid+0x50/0x80)
[    3.379716] [<c04d34d0>] (vop_crtc_mode_valid) from [<c04c983c>] (dw_hdmi_rockchip_mode_valid+0x138/0x15c)
[    3.379732] [<c04c983c>] (dw_hdmi_rockchip_mode_valid) from [<c04e26c8>] (dw_hdmi_connector_mode_valid+0x28/0x34)
[    3.379750] [<c04e26c8>] (dw_hdmi_connector_mode_valid) from [<c04998d4>] (drm_helper_probe_single_connector_modes_merge_bits+0x36c/0x448)
[    3.379767] [<c04998d4>] (drm_helper_probe_single_connector_modes_merge_bits) from [<c04999cc>] (drm_helper_probe_single_connector_modes+0x1c/0x20)
[    3.379781] [<c04999cc>] (drm_helper_probe_single_connector_modes) from [<c04a2164>] (drm_fb_helper_probe_connector_modes+0x58/0x68)
[    3.379794] [<c04a2164>] (drm_fb_helper_probe_connector_modes) from [<c04a4540>] (drm_fb_helper_hotplug_event+0x9c/0xe8)
[    3.379807] [<c04a4540>] (drm_fb_helper_hotplug_event) from [<c04d0684>] (rockchip_drm_output_poll_changed+0x28/0x2c)
[    3.379821] [<c04d0684>] (rockchip_drm_output_poll_changed) from [<c0499288>] (drm_kms_helper_hotplug_event+0x34/0x38)
[    3.379835] [<c0499288>] (drm_kms_helper_hotplug_event) from [<c0499bc4>] (drm_helper_hpd_irq_event+0x128/0x15c)
[    3.379847] [<c0499bc4>] (drm_helper_hpd_irq_event) from [<c04e2d40>] (repo_hpd_event+0x24/0x28)
[    3.379859] [<c04e2d40>] (repo_hpd_event) from [<c01347b4>] (process_one_work+0x234/0x418)
[    3.379872] [<c01347b4>] (process_one_work) from [<c0135558>] (worker_thread+0x2cc/0x40c)
[    3.379884] [<c0135558>] (worker_thread) from [<c013a0e8>] (kthread+0x100/0x118)
[    3.379898] [<c013a0e8>] (kthread) from [<c0107378>] (ret_from_fork+0x14/0x3c)

@mcerveny
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I temporary resolve this issue by workaround - https://tinkerboarding.co.uk/forum/thread-321-post-1350.html#pid1350

@markyzq
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markyzq commented Jul 11, 2017

apply attach patch, and assigned dclk on dtsi, then may solved your problem

assigned-clocks = <&cru DCLK_VOP0>;
assigned-clock-parents = <&cru PLL_NPLL>;

@markyzq
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markyzq commented Jul 11, 2017

mcerveny added a commit to mcerveny/rockchip-linux that referenced this issue Jul 11, 2017
Attach DCLK_VOP0 to NPPL and allow set rate
to allow free change monitor resolution.
WARNING: Not final fix - some frequences does not work.
test_fix: rockchip-linux#10
@mcerveny
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Thanks, but partially working.
Some resolution (NPLL/DCLK_VOP0 clock) does not work at all (blank output) or blinking (few seconds show and then resync - probably PLL lost sync ?).
Working NPLL clocks:
65000 kHz
78750 kHz
135000 kHz
NOT working NPLL clocks:
1080000 kHz (this works in my workaround perfectly eg. NPLL 216000000 and divide by 2 to get DCLK_VOP0)
75000 kHz
I suppose that PLL should use some frequency that is multiply of requested DCLK_VOP0.
I cannot view problem on TMDS clock pins with my oscilloscope to verify problem - try to test clock in your HW lab.

Test:

# egrep  'npll|dclk_vop0' /sys/kernel/debug/clk/clk_summary
    pll_npll                              1            1   108000000          0 0  
       npll                               1            1   108000000          0 0  
          dclk_vop0                       2            3   108000000          0 0  

wzyy2 pushed a commit that referenced this issue Jul 18, 2017
commit 5165da5 upstream.

Since v4.9 i2c-tiny-usb generates the below call trace
and longer works, since it can't communicate with the
USB device. The reason is, that since v4.9 the USB
stack checks, that the buffer it should transfer is DMA
capable. This was a requirement since v2.2 days, but it
usually worked nevertheless.

[   17.504959] ------------[ cut here ]------------
[   17.505488] WARNING: CPU: 0 PID: 93 at drivers/usb/core/hcd.c:1587 usb_hcd_map_urb_for_dma+0x37c/0x570
[   17.506545] transfer buffer not dma capable
[   17.507022] Modules linked in:
[   17.507370] CPU: 0 PID: 93 Comm: i2cdetect Not tainted 4.11.0-rc8+ #10
[   17.508103] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014
[   17.509039] Call Trace:
[   17.509320]  ? dump_stack+0x5c/0x78
[   17.509714]  ? __warn+0xbe/0xe0
[   17.510073]  ? warn_slowpath_fmt+0x5a/0x80
[   17.510532]  ? nommu_map_sg+0xb0/0xb0
[   17.510949]  ? usb_hcd_map_urb_for_dma+0x37c/0x570
[   17.511482]  ? usb_hcd_submit_urb+0x336/0xab0
[   17.511976]  ? wait_for_completion_timeout+0x12f/0x1a0
[   17.512549]  ? wait_for_completion_timeout+0x65/0x1a0
[   17.513125]  ? usb_start_wait_urb+0x65/0x160
[   17.513604]  ? usb_control_msg+0xdc/0x130
[   17.514061]  ? usb_xfer+0xa4/0x2a0
[   17.514445]  ? __i2c_transfer+0x108/0x3c0
[   17.514899]  ? i2c_transfer+0x57/0xb0
[   17.515310]  ? i2c_smbus_xfer_emulated+0x12f/0x590
[   17.515851]  ? _raw_spin_unlock_irqrestore+0x11/0x20
[   17.516408]  ? i2c_smbus_xfer+0x125/0x330
[   17.516876]  ? i2c_smbus_xfer+0x125/0x330
[   17.517329]  ? i2cdev_ioctl_smbus+0x1c1/0x2b0
[   17.517824]  ? i2cdev_ioctl+0x75/0x1c0
[   17.518248]  ? do_vfs_ioctl+0x9f/0x600
[   17.518671]  ? vfs_write+0x144/0x190
[   17.519078]  ? SyS_ioctl+0x74/0x80
[   17.519463]  ? entry_SYSCALL_64_fastpath+0x1e/0xad
[   17.519959] ---[ end trace d047c04982f5ac50 ]---

Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.co.uk>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Till Harbaum <till@harbaum.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
@mcerveny
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Author

Kwiboo/linux-rockchip@580da0d fixes rk3328 platform for me (not using rk3288 any more).

@mcerveny
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Author

Closing the issue due to lost confidence in Rockchip solution.

wzyy2 pushed a commit that referenced this issue Jan 30, 2018
[ Upstream commit ad0a45f ]

If a given cpu is not in cpu_present and cpu hotplug
is disabled, arch can skip setting up the cpu_dev.

Arch cpuidle driver should pass correct cpu mask
for registration, but failing to do so by the driver
causes error to propagate and crash like this:

[   30.076045] Unable to handle kernel paging request for data at address 0x00000048
[   30.076100] Faulting instruction address: 0xc0000000007b2f30
cpu 0x4d: Vector: 300 (Data Access) at [c000003feb18b670]
    pc: c0000000007b2f30: kobject_get+0x20/0x70
    lr: c0000000007b3c94: kobject_add_internal+0x54/0x3f0
    sp: c000003feb18b8f0
   msr: 9000000000009033
   dar: 48
 dsisr: 40000000
  current = 0xc000003fd2ed8300
  paca    = 0xc00000000fbab500   softe: 0        irq_happened: 0x01
    pid   = 1, comm = swapper/0
Linux version 4.11.0-rc2-svaidy+ (sv@sagarika) (gcc version 6.2.0
20161005 (Ubuntu 6.2.0-5ubuntu12) ) #10 SMP Sun Mar 19 00:08:09 IST 2017
enter ? for help
[c000003feb18b960] c0000000007b3c94 kobject_add_internal+0x54/0x3f0
[c000003feb18b9f0] c0000000007b43a4 kobject_init_and_add+0x64/0xa0
[c000003feb18ba70] c000000000e284f4 cpuidle_add_sysfs+0xb4/0x130
[c000003feb18baf0] c000000000e26038 cpuidle_register_device+0x118/0x1c0
[c000003feb18bb30] c000000000e26c48 cpuidle_register+0x78/0x120
[c000003feb18bbc0] c00000000168fd9c powernv_processor_idle_init+0x110/0x1c4
[c000003feb18bc40] c00000000000cff8 do_one_initcall+0x68/0x1d0
[c000003feb18bd00] c0000000016242f4 kernel_init_freeable+0x280/0x360
[c000003feb18bdc0] c00000000000d864 kernel_init+0x24/0x160
[c000003feb18be30] c00000000000b4e8 ret_from_kernel_thread+0x5c/0x74

Validating cpu_dev fixes the crash and reports correct error message like:

[   30.163506] Failed to register cpuidle device for cpu136
[   30.173329] Registration of powernv driver failed.

Signed-off-by: Vaidyanathan Srinivasan <svaidy@linux.vnet.ibm.com>
[ rjw: Comment massage ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
rkchrome pushed a commit that referenced this issue Jul 19, 2018
[ Upstream commit 2c0aa08 ]

Scenario:
1. Port down and do fail over
2. Ap do rds_bind syscall

PID: 47039  TASK: ffff89887e2fe640  CPU: 47  COMMAND: "kworker/u:6"
 #0 [ffff898e35f159f0] machine_kexec at ffffffff8103abf9
 #1 [ffff898e35f15a60] crash_kexec at ffffffff810b96e3
 #2 [ffff898e35f15b30] oops_end at ffffffff8150f518
 #3 [ffff898e35f15b60] no_context at ffffffff8104854c
 #4 [ffff898e35f15ba0] __bad_area_nosemaphore at ffffffff81048675
 #5 [ffff898e35f15bf0] bad_area_nosemaphore at ffffffff810487d3
 #6 [ffff898e35f15c00] do_page_fault at ffffffff815120b8
 #7 [ffff898e35f15d10] page_fault at ffffffff8150ea95
    [exception RIP: unknown or invalid address]
    RIP: 0000000000000000  RSP: ffff898e35f15dc8  RFLAGS: 00010282
    RAX: 00000000fffffffe  RBX: ffff889b77f6fc00  RCX:ffffffff81c99d88
    RDX: 0000000000000000  RSI: ffff896019ee08e8  RDI:ffff889b77f6fc00
    RBP: ffff898e35f15df0   R8: ffff896019ee08c8  R9:0000000000000000
    R10: 0000000000000400  R11: 0000000000000000  R12:ffff896019ee08c0
    R13: ffff889b77f6fe68  R14: ffffffff81c99d80  R15: ffffffffa022a1e0
    ORIG_RAX: ffffffffffffffff  CS: 0010 SS: 0018
 #8 [ffff898e35f15dc8] cma_ndev_work_handler at ffffffffa022a228 [rdma_cm]
 #9 [ffff898e35f15df8] process_one_work at ffffffff8108a7c6
 #10 [ffff898e35f15e58] worker_thread at ffffffff8108bda0
 #11 [ffff898e35f15ee8] kthread at ffffffff81090fe6

PID: 45659  TASK: ffff880d313d2500  CPU: 31  COMMAND: "oracle_45659_ap"
 #0 [ffff881024ccfc98] __schedule at ffffffff8150bac4
 #1 [ffff881024ccfd40] schedule at ffffffff8150c2cf
 #2 [ffff881024ccfd50] __mutex_lock_slowpath at ffffffff8150cee7
 #3 [ffff881024ccfdc0] mutex_lock at ffffffff8150cdeb
 #4 [ffff881024ccfde0] rdma_destroy_id at ffffffffa022a027 [rdma_cm]
 #5 [ffff881024ccfe10] rds_ib_laddr_check at ffffffffa0357857 [rds_rdma]
 #6 [ffff881024ccfe50] rds_trans_get_preferred at ffffffffa0324c2a [rds]
 #7 [ffff881024ccfe80] rds_bind at ffffffffa031d690 [rds]
 #8 [ffff881024ccfeb0] sys_bind at ffffffff8142a670

PID: 45659                          PID: 47039
rds_ib_laddr_check
  /* create id_priv with a null event_handler */
  rdma_create_id
  rdma_bind_addr
    cma_acquire_dev
      /* add id_priv to cma_dev->id_list */
      cma_attach_to_dev
                                    cma_ndev_work_handler
                                      /* event_hanlder is null */
                                      id_priv->id.event_handler

Signed-off-by: Guanglei Li <guanglei.li@oracle.com>
Signed-off-by: Honglei Wang <honglei.wang@oracle.com>
Reviewed-by: Junxiao Bi <junxiao.bi@oracle.com>
Reviewed-by: Yanjun Zhu <yanjun.zhu@oracle.com>
Reviewed-by: Leon Romanovsky <leonro@mellanox.com>
Acked-by: Santosh Shilimkar <santosh.shilimkar@oracle.com>
Acked-by: Doug Ledford <dledford@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
rkchrome pushed a commit that referenced this issue Jul 19, 2018
[ Upstream commit 2bbea6e ]

when mounting an ISO filesystem sometimes (very rarely)
the system hangs because of a race condition between two tasks.

PID: 6766   TASK: ffff88007b2a6dd0  CPU: 0   COMMAND: "mount"
 #0 [ffff880078447ae0] __schedule at ffffffff8168d605
 #1 [ffff880078447b48] schedule_preempt_disabled at ffffffff8168ed49
 #2 [ffff880078447b58] __mutex_lock_slowpath at ffffffff8168c995
 #3 [ffff880078447bb8] mutex_lock at ffffffff8168bdef
 #4 [ffff880078447bd0] sr_block_ioctl at ffffffffa00b6818 [sr_mod]
 #5 [ffff880078447c10] blkdev_ioctl at ffffffff812fea50
 #6 [ffff880078447c70] ioctl_by_bdev at ffffffff8123a8b3
 #7 [ffff880078447c90] isofs_fill_super at ffffffffa04fb1e1 [isofs]
 #8 [ffff880078447da8] mount_bdev at ffffffff81202570
 #9 [ffff880078447e18] isofs_mount at ffffffffa04f9828 [isofs]
#10 [ffff880078447e28] mount_fs at ffffffff81202d09
#11 [ffff880078447e70] vfs_kern_mount at ffffffff8121ea8f
#12 [ffff880078447ea8] do_mount at ffffffff81220fee
#13 [ffff880078447f28] sys_mount at ffffffff812218d6
#14 [ffff880078447f80] system_call_fastpath at ffffffff81698c49
    RIP: 00007fd9ea914e9a  RSP: 00007ffd5d9bf648  RFLAGS: 00010246
    RAX: 00000000000000a5  RBX: ffffffff81698c49  RCX: 0000000000000010
    RDX: 00007fd9ec2bc210  RSI: 00007fd9ec2bc290  RDI: 00007fd9ec2bcf30
    RBP: 0000000000000000   R8: 0000000000000000   R9: 0000000000000010
    R10: 00000000c0ed0001  R11: 0000000000000206  R12: 00007fd9ec2bc040
    R13: 00007fd9eb6b2380  R14: 00007fd9ec2bc210  R15: 00007fd9ec2bcf30
    ORIG_RAX: 00000000000000a5  CS: 0033  SS: 002b

This task was trying to mount the cdrom.  It allocated and configured a
super_block struct and owned the write-lock for the super_block->s_umount
rwsem. While exclusively owning the s_umount lock, it called
sr_block_ioctl and waited to acquire the global sr_mutex lock.

PID: 6785   TASK: ffff880078720fb0  CPU: 0   COMMAND: "systemd-udevd"
 #0 [ffff880078417898] __schedule at ffffffff8168d605
 #1 [ffff880078417900] schedule at ffffffff8168dc59
 #2 [ffff880078417910] rwsem_down_read_failed at ffffffff8168f605
 #3 [ffff880078417980] call_rwsem_down_read_failed at ffffffff81328838
 #4 [ffff8800784179d0] down_read at ffffffff8168cde0
 #5 [ffff8800784179e8] get_super at ffffffff81201cc7
 #6 [ffff880078417a10] __invalidate_device at ffffffff8123a8de
 #7 [ffff880078417a40] flush_disk at ffffffff8123a94b
 #8 [ffff880078417a88] check_disk_change at ffffffff8123ab50
 #9 [ffff880078417ab0] cdrom_open at ffffffffa00a29e1 [cdrom]
#10 [ffff880078417b68] sr_block_open at ffffffffa00b6f9b [sr_mod]
#11 [ffff880078417b98] __blkdev_get at ffffffff8123ba86
#12 [ffff880078417bf0] blkdev_get at ffffffff8123bd65
#13 [ffff880078417c78] blkdev_open at ffffffff8123bf9b
#14 [ffff880078417c90] do_dentry_open at ffffffff811fc7f7
#15 [ffff880078417cd8] vfs_open at ffffffff811fc9cf
#16 [ffff880078417d00] do_last at ffffffff8120d53d
#17 [ffff880078417db0] path_openat at ffffffff8120e6b2
#18 [ffff880078417e48] do_filp_open at ffffffff8121082b
#19 [ffff880078417f18] do_sys_open at ffffffff811fdd33
#20 [ffff880078417f70] sys_open at ffffffff811fde4e
#21 [ffff880078417f80] system_call_fastpath at ffffffff81698c49
    RIP: 00007f29438b0c20  RSP: 00007ffc76624b78  RFLAGS: 00010246
    RAX: 0000000000000002  RBX: ffffffff81698c49  RCX: 0000000000000000
    RDX: 00007f2944a5fa70  RSI: 00000000000a0800  RDI: 00007f2944a5fa70
    RBP: 00007f2944a5f540   R8: 0000000000000000   R9: 0000000000000020
    R10: 00007f2943614c40  R11: 0000000000000246  R12: ffffffff811fde4e
    R13: ffff880078417f78  R14: 000000000000000c  R15: 00007f2944a4b010
    ORIG_RAX: 0000000000000002  CS: 0033  SS: 002b

This task tried to open the cdrom device, the sr_block_open function
acquired the global sr_mutex lock. The call to check_disk_change()
then saw an event flag indicating a possible media change and tried
to flush any cached data for the device.
As part of the flush, it tried to acquire the super_block->s_umount
lock associated with the cdrom device.
This was the same super_block as created and locked by the previous task.

The first task acquires the s_umount lock and then the sr_mutex_lock;
the second task acquires the sr_mutex_lock and then the s_umount lock.

This patch fixes the issue by moving check_disk_change() out of
cdrom_open() and let the caller take care of it.

Signed-off-by: Maurizio Lombardi <mlombard@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
rkchrome pushed a commit that referenced this issue Sep 26, 2018
[ Upstream commit 2c0aa08 ]

Scenario:
1. Port down and do fail over
2. Ap do rds_bind syscall

PID: 47039  TASK: ffff89887e2fe640  CPU: 47  COMMAND: "kworker/u:6"
 #0 [ffff898e35f159f0] machine_kexec at ffffffff8103abf9
 #1 [ffff898e35f15a60] crash_kexec at ffffffff810b96e3
 #2 [ffff898e35f15b30] oops_end at ffffffff8150f518
 #3 [ffff898e35f15b60] no_context at ffffffff8104854c
 #4 [ffff898e35f15ba0] __bad_area_nosemaphore at ffffffff81048675
 #5 [ffff898e35f15bf0] bad_area_nosemaphore at ffffffff810487d3
 #6 [ffff898e35f15c00] do_page_fault at ffffffff815120b8
 #7 [ffff898e35f15d10] page_fault at ffffffff8150ea95
    [exception RIP: unknown or invalid address]
    RIP: 0000000000000000  RSP: ffff898e35f15dc8  RFLAGS: 00010282
    RAX: 00000000fffffffe  RBX: ffff889b77f6fc00  RCX:ffffffff81c99d88
    RDX: 0000000000000000  RSI: ffff896019ee08e8  RDI:ffff889b77f6fc00
    RBP: ffff898e35f15df0   R8: ffff896019ee08c8  R9:0000000000000000
    R10: 0000000000000400  R11: 0000000000000000  R12:ffff896019ee08c0
    R13: ffff889b77f6fe68  R14: ffffffff81c99d80  R15: ffffffffa022a1e0
    ORIG_RAX: ffffffffffffffff  CS: 0010 SS: 0018
 #8 [ffff898e35f15dc8] cma_ndev_work_handler at ffffffffa022a228 [rdma_cm]
 #9 [ffff898e35f15df8] process_one_work at ffffffff8108a7c6
 #10 [ffff898e35f15e58] worker_thread at ffffffff8108bda0
 #11 [ffff898e35f15ee8] kthread at ffffffff81090fe6

PID: 45659  TASK: ffff880d313d2500  CPU: 31  COMMAND: "oracle_45659_ap"
 #0 [ffff881024ccfc98] __schedule at ffffffff8150bac4
 #1 [ffff881024ccfd40] schedule at ffffffff8150c2cf
 #2 [ffff881024ccfd50] __mutex_lock_slowpath at ffffffff8150cee7
 #3 [ffff881024ccfdc0] mutex_lock at ffffffff8150cdeb
 #4 [ffff881024ccfde0] rdma_destroy_id at ffffffffa022a027 [rdma_cm]
 #5 [ffff881024ccfe10] rds_ib_laddr_check at ffffffffa0357857 [rds_rdma]
 #6 [ffff881024ccfe50] rds_trans_get_preferred at ffffffffa0324c2a [rds]
 #7 [ffff881024ccfe80] rds_bind at ffffffffa031d690 [rds]
 #8 [ffff881024ccfeb0] sys_bind at ffffffff8142a670

PID: 45659                          PID: 47039
rds_ib_laddr_check
  /* create id_priv with a null event_handler */
  rdma_create_id
  rdma_bind_addr
    cma_acquire_dev
      /* add id_priv to cma_dev->id_list */
      cma_attach_to_dev
                                    cma_ndev_work_handler
                                      /* event_hanlder is null */
                                      id_priv->id.event_handler

Signed-off-by: Guanglei Li <guanglei.li@oracle.com>
Signed-off-by: Honglei Wang <honglei.wang@oracle.com>
Reviewed-by: Junxiao Bi <junxiao.bi@oracle.com>
Reviewed-by: Yanjun Zhu <yanjun.zhu@oracle.com>
Reviewed-by: Leon Romanovsky <leonro@mellanox.com>
Acked-by: Santosh Shilimkar <santosh.shilimkar@oracle.com>
Acked-by: Doug Ledford <dledford@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
rkchrome pushed a commit that referenced this issue Sep 26, 2018
[ Upstream commit 2bbea6e ]

when mounting an ISO filesystem sometimes (very rarely)
the system hangs because of a race condition between two tasks.

PID: 6766   TASK: ffff88007b2a6dd0  CPU: 0   COMMAND: "mount"
 #0 [ffff880078447ae0] __schedule at ffffffff8168d605
 #1 [ffff880078447b48] schedule_preempt_disabled at ffffffff8168ed49
 #2 [ffff880078447b58] __mutex_lock_slowpath at ffffffff8168c995
 #3 [ffff880078447bb8] mutex_lock at ffffffff8168bdef
 #4 [ffff880078447bd0] sr_block_ioctl at ffffffffa00b6818 [sr_mod]
 #5 [ffff880078447c10] blkdev_ioctl at ffffffff812fea50
 #6 [ffff880078447c70] ioctl_by_bdev at ffffffff8123a8b3
 #7 [ffff880078447c90] isofs_fill_super at ffffffffa04fb1e1 [isofs]
 #8 [ffff880078447da8] mount_bdev at ffffffff81202570
 #9 [ffff880078447e18] isofs_mount at ffffffffa04f9828 [isofs]
#10 [ffff880078447e28] mount_fs at ffffffff81202d09
#11 [ffff880078447e70] vfs_kern_mount at ffffffff8121ea8f
#12 [ffff880078447ea8] do_mount at ffffffff81220fee
#13 [ffff880078447f28] sys_mount at ffffffff812218d6
#14 [ffff880078447f80] system_call_fastpath at ffffffff81698c49
    RIP: 00007fd9ea914e9a  RSP: 00007ffd5d9bf648  RFLAGS: 00010246
    RAX: 00000000000000a5  RBX: ffffffff81698c49  RCX: 0000000000000010
    RDX: 00007fd9ec2bc210  RSI: 00007fd9ec2bc290  RDI: 00007fd9ec2bcf30
    RBP: 0000000000000000   R8: 0000000000000000   R9: 0000000000000010
    R10: 00000000c0ed0001  R11: 0000000000000206  R12: 00007fd9ec2bc040
    R13: 00007fd9eb6b2380  R14: 00007fd9ec2bc210  R15: 00007fd9ec2bcf30
    ORIG_RAX: 00000000000000a5  CS: 0033  SS: 002b

This task was trying to mount the cdrom.  It allocated and configured a
super_block struct and owned the write-lock for the super_block->s_umount
rwsem. While exclusively owning the s_umount lock, it called
sr_block_ioctl and waited to acquire the global sr_mutex lock.

PID: 6785   TASK: ffff880078720fb0  CPU: 0   COMMAND: "systemd-udevd"
 #0 [ffff880078417898] __schedule at ffffffff8168d605
 #1 [ffff880078417900] schedule at ffffffff8168dc59
 #2 [ffff880078417910] rwsem_down_read_failed at ffffffff8168f605
 #3 [ffff880078417980] call_rwsem_down_read_failed at ffffffff81328838
 #4 [ffff8800784179d0] down_read at ffffffff8168cde0
 #5 [ffff8800784179e8] get_super at ffffffff81201cc7
 #6 [ffff880078417a10] __invalidate_device at ffffffff8123a8de
 #7 [ffff880078417a40] flush_disk at ffffffff8123a94b
 #8 [ffff880078417a88] check_disk_change at ffffffff8123ab50
 #9 [ffff880078417ab0] cdrom_open at ffffffffa00a29e1 [cdrom]
#10 [ffff880078417b68] sr_block_open at ffffffffa00b6f9b [sr_mod]
#11 [ffff880078417b98] __blkdev_get at ffffffff8123ba86
#12 [ffff880078417bf0] blkdev_get at ffffffff8123bd65
#13 [ffff880078417c78] blkdev_open at ffffffff8123bf9b
#14 [ffff880078417c90] do_dentry_open at ffffffff811fc7f7
#15 [ffff880078417cd8] vfs_open at ffffffff811fc9cf
#16 [ffff880078417d00] do_last at ffffffff8120d53d
#17 [ffff880078417db0] path_openat at ffffffff8120e6b2
#18 [ffff880078417e48] do_filp_open at ffffffff8121082b
#19 [ffff880078417f18] do_sys_open at ffffffff811fdd33
#20 [ffff880078417f70] sys_open at ffffffff811fde4e
#21 [ffff880078417f80] system_call_fastpath at ffffffff81698c49
    RIP: 00007f29438b0c20  RSP: 00007ffc76624b78  RFLAGS: 00010246
    RAX: 0000000000000002  RBX: ffffffff81698c49  RCX: 0000000000000000
    RDX: 00007f2944a5fa70  RSI: 00000000000a0800  RDI: 00007f2944a5fa70
    RBP: 00007f2944a5f540   R8: 0000000000000000   R9: 0000000000000020
    R10: 00007f2943614c40  R11: 0000000000000246  R12: ffffffff811fde4e
    R13: ffff880078417f78  R14: 000000000000000c  R15: 00007f2944a4b010
    ORIG_RAX: 0000000000000002  CS: 0033  SS: 002b

This task tried to open the cdrom device, the sr_block_open function
acquired the global sr_mutex lock. The call to check_disk_change()
then saw an event flag indicating a possible media change and tried
to flush any cached data for the device.
As part of the flush, it tried to acquire the super_block->s_umount
lock associated with the cdrom device.
This was the same super_block as created and locked by the previous task.

The first task acquires the s_umount lock and then the sr_mutex_lock;
the second task acquires the sr_mutex_lock and then the s_umount lock.

This patch fixes the issue by moving check_disk_change() out of
cdrom_open() and let the caller take care of it.

Signed-off-by: Maurizio Lombardi <mlombard@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
0lvin referenced this issue in free-z4u/roc-rk3328-cc-official Jan 12, 2019
…rive

This patch fixes Machine Check "Data Write PLB Error" which happens
when libata-sff's ata_sff_dev_select is trying to write into the
device_addr in order to select a drive. However, SATA has no master
or slave devices like the old ATA Bus, therefore selecting a
different drive is kind of pointless.

Data Write PLB Error
Oops: Machine check, sig: 7 [FireflyTeam#1]
PowerPC 44x Platform
Modules linked in:
CPU: 0 PID: 508 Comm: scsi_eh_0 Not tainted 4.6.0-rc3-next-20160412+ FireflyTeam#10
[...]
NIP [c027e820] ata_sff_dev_select+0x3c/0x44
LR [c027e810] ata_sff_dev_select+0x2c/0x44
Call Trace:
[cec31cd0] [c027da00] ata_sff_postreset+0x40/0xb4 (unreliable)
[cec31ce0] [c027a03c] ata_eh_reset+0x5cc/0x928
[cec31d60] [c027a840] ata_eh_recover+0x330/0x10bc
[cec31df0] [c027bae0] ata_do_eh+0x4c/0xa4
[...]

Signed-off-by: Christian Lamparter <chunkeey@googlemail.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
0lvin referenced this issue in free-z4u/roc-rk3328-cc-official Feb 2, 2019
Don't free the object until the file handle has been closed.  Fixes
use-after-free bug which occurs when I disconnect my DVB-S received
while VDR is running.

This is a crash dump of such a use-after-free:

    general protection fault: 0000 [FireflyTeam#1] SMP
    CPU: 0 PID: 2541 Comm: CI adapter on d Not tainted 4.7.0-rc1-hosting+ rockchip-linux#49
    Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
    task: ffff880027d7ce00 ti: ffff88003d8f8000 task.ti: ffff88003d8f8000
    RIP: 0010:[<ffffffff812f3d1f>]  [<ffffffff812f3d1f>] dvb_ca_en50221_io_read_condition.isra.7+0x6f/0x150
    RSP: 0018:ffff88003d8fba98  EFLAGS: 00010206
    RAX: 0000000059534255 RBX: 000000753d470f90 RCX: ffff88003c74d181
    RDX: 00000001bea04ba9 RSI: ffff88003d8fbaf4 RDI: 3a3030a56d763fc0
    RBP: ffff88003d8fbae0 R08: ffff88003c74d180 R09: 0000000000000000
    R10: 0000000000000001 R11: 0000000000000000 R12: ffff88003c480e00
    R13: 00000000ffffffff R14: 0000000059534255 R15: 0000000000000000
    FS:  00007fb4209b4700(0000) GS:ffff88003fc00000(0000) knlGS:0000000000000000
    CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
    CR2: 00007f06445f4078 CR3: 000000003c55b000 CR4: 00000000000006b0
    Stack:
     ffff88003d8fbaf4 000000003c2170c0 0000000000004000 0000000000000000
     ffff88003c480e00 ffff88003d8fbc80 ffff88003c74d180 ffff88003d8fbb8c
     0000000000000000 ffff88003d8fbb10 ffffffff812f3e37 ffff88003d8fbb00
    Call Trace:
     [<ffffffff812f3e37>] dvb_ca_en50221_io_poll+0x37/0xa0
     [<ffffffff8113109b>] do_sys_poll+0x2db/0x520

This is a backtrace of the kernel attempting to lock a freed mutex:

    #0  0xffffffff81083d40 in rep_nop () at ./arch/x86/include/asm/processor.h:569
    FireflyTeam#1  cpu_relax () at ./arch/x86/include/asm/processor.h:574
    FireflyTeam#2  virt_spin_lock (lock=<optimized out>) at ./arch/x86/include/asm/qspinlock.h:57
    FireflyTeam#3  native_queued_spin_lock_slowpath (lock=0xffff88003c480e90, val=761492029) at kernel/locking/qspinlock.c:304
    FireflyTeam#4  0xffffffff810d1a06 in pv_queued_spin_lock_slowpath (val=<optimized out>, lock=<optimized out>) at ./arch/x86/include/asm/paravirt.h:669
    FireflyTeam#5  queued_spin_lock_slowpath (val=<optimized out>, lock=<optimized out>) at ./arch/x86/include/asm/qspinlock.h:28
    FireflyTeam#6  queued_spin_lock (lock=<optimized out>) at include/asm-generic/qspinlock.h:107
    FireflyTeam#7  __mutex_lock_common (use_ww_ctx=<optimized out>, ww_ctx=<optimized out>, ip=<optimized out>, nest_lock=<optimized out>, subclass=<optimized out>,
        state=<optimized out>, lock=<optimized out>) at kernel/locking/mutex.c:526
    FireflyTeam#8  mutex_lock_interruptible_nested (lock=0xffff88003c480e88, subclass=<optimized out>) at kernel/locking/mutex.c:647
    FireflyTeam#9  0xffffffff812f49fe in dvb_ca_en50221_io_do_ioctl (file=<optimized out>, cmd=761492029, parg=0x1 <irq_stack_union+1>)
        at drivers/media/dvb-core/dvb_ca_en50221.c:1210
    FireflyTeam#10 0xffffffff812ee660 in dvb_usercopy (file=<optimized out>, cmd=761492029, arg=<optimized out>, func=<optimized out>) at drivers/media/dvb-core/dvbdev.c:883
    FireflyTeam#11 0xffffffff812f3410 in dvb_ca_en50221_io_ioctl (file=<optimized out>, cmd=<optimized out>, arg=<optimized out>) at drivers/media/dvb-core/dvb_ca_en50221.c:1284
    FireflyTeam#12 0xffffffff8112eddd in vfs_ioctl (arg=<optimized out>, cmd=<optimized out>, filp=<optimized out>) at fs/ioctl.c:43
    FireflyTeam#13 do_vfs_ioctl (filp=0xffff88003c480e90, fd=<optimized out>, cmd=<optimized out>, arg=<optimized out>) at fs/ioctl.c:674
    FireflyTeam#14 0xffffffff8112f30c in SYSC_ioctl (arg=<optimized out>, cmd=<optimized out>, fd=<optimized out>) at fs/ioctl.c:689
    FireflyTeam#15 SyS_ioctl (fd=6, cmd=2148298626, arg=140734533693696) at fs/ioctl.c:680
    FireflyTeam#16 0xffffffff8103feb2 in entry_SYSCALL_64 () at arch/x86/entry/entry_64.S:207

Signed-off-by: Max Kellermann <max@duempel.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
0lvin referenced this issue in free-z4u/roc-rk3328-cc-official Feb 9, 2019
Saeed Mahameed says:

====================
Mellanox 100G SRIOV E-Switch offload and VF representors

We are happy to announce SRIOV E-Switch offload and VF netdev representors.

Or Gerlitz says:

Currently, the way SR-IOV embedded switches are dealt with in Linux is limited
in its expressiveness and flexibility, but this is not necessarily due to
hardware limitations. The kernel software model for controlling the SR-IOV
switch simply does not allow the configuration of anything more complex than
MAC/VLAN based forwarding.

Hence the benefits brought by SRIOV come at a price of management flexibility,
when compared to software virtual switches which are used in Para-Virtual (PV)
schemes and allow implementing complex policies and virtual topologies. Such
SW switching typically involved a complex per-packet processing within the host
kernel using subsystems such as TC, Bridge, Netfilter and Open-vswitch.

We'd like to change that and get the best of both worlds: the performance of SR-IOV
with the management flexibility of software switches. This will eventually include
a richer model for controlling the SR-IOV switch for flow-based switching and
tunneling. Under this model, the e-switch is configured dynamically and a fallback
to software exists in case the hardware is unable to offload all required flows.

This series from Hadar Hen-Zion and myself, is the 1st step in that direction,
specfically, it provides full control on the SRIOV embedded switching by host
software and paves the way to offload switching rules and polices with downstream
patches.

To allow for host based SW control on the SRIOV HW switch, we introduce per VF
representor host netdevice. The VF representor plays the same role as TAP devices
in PV setup. A packet send through the VF representor on the host arrives to
the VF, and a packet sent through the VF is received by its representor. The
administrator can hook the representor netdev into a kernel switching component.
Once they do that, packets from the VF are subject to steering (matching and
actions) of that software component."

Doing so indeed hurts the performance benefits of SRIOV as it forces all the
traffic to go through the hypervisor. However, this SW representation is what
would eventually allow us to introduce hybrid model, where we offload steering
for some of the VF/VM traffic to the HW while keeping other VM traffic to go
through the hypervisor. Examples for the latter are first packet of flows which
are needed for SW switches learning and/or matching against policy database or
types of traffic for which offloading is not desired or not supported by the
current HW eswitch generation.

The embedded switch is managed through a PCI device driver. As such, we introduce
a devlink/pci based scheme for setting the mode of the e-switch. The current mode
(where steering is done based on mac/vlan, etc) is referred to as "legacy" and the
new mode as "offloads".

For the mlx5 driver / ConnectX4 HW case, the VF representors implement a functional
subset of mlx5e Ethernet netdevices using their own profile. This design buys us robust
implementation with code reuse and sharing.

The representors are created by the host PCI driver when (1) in SRIOV and (2) the
e-switch is set to offloads mode. Currently, in mlx5 the e-switch management is done
through the PF vport (0) and hence the VF representors along with the existing PF
netdev which represents the uplink share the PCI PF device instance.

The series is built from two major components, the first relates to the e-switch
management and the second to VF representors.

We start with a refactoring that treats the existing SRIOV e-switch code as of operating
in legacy mode. Next, we add the code for the offloads mode which programs the e-switch
to operate in a way which serves for software based switching:

1. miss rule which matches all packets that do not match any HW other switching rule
and forwards them to the e-switch management port (0) for further processing.

2. infrastructure for send-to-vport rules which conceptually bypass other "normal"
steering rules which present at the e-switch datapath. Such rules apply only for packets
that originate in the e-switch manager vport (0).

Since all the VF reps run over the same e-switch port, we use more logic in the host PCI
driver to do HW steering of missed packets into the HW queue opened by a the respective VF
representor. Finally here, we add the devlink APIs to configure the e-switch mode.

The second part from Hadar starts with some refactoring work which allow for multiple
mlx5e NIC instances to be created over the same PCI function, use common resources
and avoid wrong loopbacks.

Next comes the heart of the change which is a profile definition which allow to practically
have both "conventional" mlx5e NIC use cases such as native mode (non SRIOV), VF, PF and VF
representor to share the Ethernet driver code. This is done by a small surgery that ended up
with few internal callbacks that should be implemented by a profile instance. The profile
for the conventional NIC is implemented, to preserve the existing functionality.

The last two patches add e-switch registration API for the VF representors and the
implementation of the VF representors netdevice profile. Being an mlx5e instance, the
VF representor uses HW send/recv queues, completions queues and such. It currently doesn't
support NIC offloads but some of them could be added later on. The VF representor has
switchdev ops, where currently the only supported API is the one to the HW ID,
which is needed to identify multiple representors belonging to the same e-switch.

The architecture + solution (software and firmware) work were done by a team consisting
of Ilya Lesokhin, Haggai Eran, Rony Efraim, Tal Anker, Natan Oppenheimer, Saeed Mahameed,
Hadar and Or, thanks you all!

v1 --> v2 fixes:
* removed unneeded variable (patch FireflyTeam#3)
* removed unused value DEVLINK_ESWITCH_MODE_NONE (patch FireflyTeam#8)
* changed the devlink mode name from "offloads" to "switchdev" which
   better describes what are we referring here, using a known concept (patch FireflyTeam#8)
* correctly refer to devlink e-switch modes (patch FireflyTeam#10)
* use the correct mlx5e way to define the VF rep statistics  (patch FireflyTeam#16)

v2 --> v3 fixes:
* Rebased on top 6fde0e6 'be2net: signedness bug in be_msix_enable()'
* Handled compilation error introduced by rebase on top "f5074d0ce2f8 Merge branch 'mlx5-100G-fixes'"
* This series applies perfectly even with 'mlx5 resiliency and xmit path fixes' merged to net-next
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
0lvin referenced this issue in free-z4u/roc-rk3328-cc-official Mar 10, 2019
First loop in wait_for_xmitr could also trigger NMI
watchdog in case reading from the port is slow:

  PID: 0      TASK: ffffffff819c1460  CPU: 0   COMMAND: "swapper/0"
   #0 [ffff88019f405e58] crash_nmi_callback at ffffffff8104d382
   FireflyTeam#1 [ffff88019f405e68] nmi_handle at ffffffff8168ead9
   FireflyTeam#2 [ffff88019f405eb0] do_nmi at ffffffff8168ec53
   FireflyTeam#3 [ffff88019f405ef0] end_repeat_nmi at ffffffff8168df13
      [exception RIP: delay_tsc+50]
      RIP: ffffffff81325642  RSP: ffff88019f403bb0  RFLAGS: 00000083
      RAX: 00000000000005c8  RBX: ffffffff81f83000  RCX: 0000024e4fb88a8b
      RDX: 0000024e4fb89053  RSI: 0000000000000000  RDI: 00000000000007d1
      RBP: ffff88019f403bb0   R8: 000000000000000a   R9: 0000000000000000
      R10: 0000000000000000  R11: ffff88019f403ad6  R12: 000000000000250f
      R13: 0000000000000020  R14: ffffffff81d360c7  R15: 0000000000000047
      ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0018
  --- <NMI exception stack> ---
   FireflyTeam#4 [ffff88019f403bb0] delay_tsc at ffffffff81325642
   FireflyTeam#5 [ffff88019f403bb8] __const_udelay at ffffffff813255a8
   FireflyTeam#6 [ffff88019f403bc8] wait_for_xmitr at ffffffff81404390
   FireflyTeam#7 [ffff88019f403bf0] serial8250_console_putchar at ffffffff8140455c
   FireflyTeam#8 [ffff88019f403c10] uart_console_write at ffffffff813ff00a
   FireflyTeam#9 [ffff88019f403c40] serial8250_console_write at ffffffff814044ae
  FireflyTeam#10 [ffff88019f403c88] call_console_drivers.constprop.15 at ffffffff81086b01
  FireflyTeam#11 [ffff88019f403cb0] console_unlock at ffffffff8108842f
  FireflyTeam#12 [ffff88019f403ce8] vprintk_emit at ffffffff81088834
  FireflyTeam#13 [ffff88019f403d58] vprintk_default at ffffffff81088ba9
  FireflyTeam#14 [ffff88019f403d68] printk at ffffffff8167f034

Adding touch_nmi_watchdog call to the first loop as well.

Reported-by: Chunyu Hu <chuhu@redhat.com>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
0lvin referenced this issue in free-z4u/roc-rk3328-cc-official Apr 14, 2019
Fixed the following checkpatch warnings (task FireflyTeam#10 of eudyptula challenge):
- NULL comparison rewritten to use '!' operator

Signed-off-by: Carlos Palminha <palminha@synopsys.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
0lvin referenced this issue in free-z4u/roc-rk3328-cc-official Apr 27, 2019
Function ib_create_qp() was failing to return an error when
rdma_rw_init_mrs() fails, causing a crash further down in ib_create_qp()
when trying to dereferece the qp pointer which was actually a negative
errno.

The crash:

crash> log|grep BUG
[  136.458121] BUG: unable to handle kernel NULL pointer dereference at 0000000000000098
crash> bt
PID: 3736   TASK: ffff8808543215c0  CPU: 2   COMMAND: "kworker/u64:2"
 #0 [ffff88084d323340] machine_kexec at ffffffff8105fbb0
 FireflyTeam#1 [ffff88084d3233b0] __crash_kexec at ffffffff81116758
 FireflyTeam#2 [ffff88084d323480] crash_kexec at ffffffff8111682d
 FireflyTeam#3 [ffff88084d3234b0] oops_end at ffffffff81032bd6
 FireflyTeam#4 [ffff88084d3234e0] no_context at ffffffff8106e431
 FireflyTeam#5 [ffff88084d323530] __bad_area_nosemaphore at ffffffff8106e610
 FireflyTeam#6 [ffff88084d323590] bad_area_nosemaphore at ffffffff8106e6f4
 FireflyTeam#7 [ffff88084d3235a0] __do_page_fault at ffffffff8106ebdc
 FireflyTeam#8 [ffff88084d323620] do_page_fault at ffffffff8106f057
 FireflyTeam#9 [ffff88084d323660] page_fault at ffffffff816e3148
    [exception RIP: ib_create_qp+427]
    RIP: ffffffffa02554fb  RSP: ffff88084d323718  RFLAGS: 00010246
    RAX: 0000000000000004  RBX: fffffffffffffff4  RCX: 000000018020001f
    RDX: ffff880830997fc0  RSI: 0000000000000001  RDI: ffff88085f407200
    RBP: ffff88084d323778   R8: 0000000000000001   R9: ffffea0020bae210
    R10: ffffea0020bae218  R11: 0000000000000001  R12: ffff88084d3237c8
    R13: 00000000fffffff4  R14: ffff880859fa5000  R15: ffff88082eb89800
    ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0018
FireflyTeam#10 [ffff88084d323780] rdma_create_qp at ffffffffa0782681 [rdma_cm]
FireflyTeam#11 [ffff88084d3237b0] nvmet_rdma_create_queue_ib at ffffffffa07c43f3 [nvmet_rdma]
FireflyTeam#12 [ffff88084d323860] nvmet_rdma_alloc_queue at ffffffffa07c5ba9 [nvmet_rdma]
FireflyTeam#13 [ffff88084d323900] nvmet_rdma_queue_connect at ffffffffa07c5c96 [nvmet_rdma]
FireflyTeam#14 [ffff88084d323980] nvmet_rdma_cm_handler at ffffffffa07c6450 [nvmet_rdma]
FireflyTeam#15 [ffff88084d3239b0] iw_conn_req_handler at ffffffffa0787480 [rdma_cm]
FireflyTeam#16 [ffff88084d323a60] cm_conn_req_handler at ffffffffa0775f06 [iw_cm]
rockchip-linux#17 [ffff88084d323ab0] process_event at ffffffffa0776019 [iw_cm]
rockchip-linux#18 [ffff88084d323af0] cm_work_handler at ffffffffa0776170 [iw_cm]
rockchip-linux#19 [ffff88084d323cb0] process_one_work at ffffffff810a1483
rockchip-linux#20 [ffff88084d323d90] worker_thread at ffffffff810a211d
rockchip-linux#21 [ffff88084d323ec0] kthread at ffffffff810a6c5c
rockchip-linux#22 [ffff88084d323f50] ret_from_fork at ffffffff816e1ebf

Fixes: 632bc3f ("IB/core, RDMA RW API: Do not exceed QP SGE send limit")
Signed-off-by: Steve Wise <swise@opengridcomputing.com>
Cc: stable@vger.kernel.org
Reviewed-by: Bart Van Assche <bart.vanassche@sandisk.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
0lvin referenced this issue in free-z4u/roc-rk3328-cc-official May 9, 2019
Yuval Mintz says:

====================
qed*: Add XDP support

This patch series is intended to add XDP to the qede driver, although
it contains quite a bit of cleanups, refactorings and infrastructure
changes as well.

The content of this series can be roughly divided into:

 - Datapath improvements - mostly focused on having the datapath utilize
parameters which can be more tightly contained in cachelines.
Patches FireflyTeam#1, FireflyTeam#2, FireflyTeam#8, FireflyTeam#9 belong to this group.

 - Refactoring - done mostly in favour of XDP. Patches FireflyTeam#3, FireflyTeam#4, FireflyTeam#5, FireflyTeam#9.

 - Infrastructure changes - done in favour of XDP. Paches FireflyTeam#6 and FireflyTeam#7 belong
to this category [FireflyTeam#7 being by far the biggest patch in the series].

 - Actual XDP support - last two patches [FireflyTeam#10, FireflyTeam#11].
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
0lvin referenced this issue in free-z4u/roc-rk3328-cc-official Jun 2, 2019
The HID report buffers that are initially allocated on i2c_hid_probe()
might not be big enough to hold the HID reports from a specific device,
in which case they will be freed and new ones will be allocated in
i2c_hid_start(), at point which the device's report size is known. But
at this point ihid->irq is already running, and may call
i2c_hid_get_input() which passes ihid->inbuf to i2c_master_recv(). Since
this handler runs in a separate thread, ihid->inbuf may be freed at this
very moment, and i2c_master_recv() will write on memory which may be
already owned by a different part of the kernel, corrupting its data.

This problem has been observed on an Asus UX360UA laptop which has an
I2C touchpad, and results in a complete system freeze or an unusable
slowness with a lof of "BUG: unable to handle kernel paging request at
<address>" warnings. Enabling SLUB debugging shows a use-after-free
warning on memory allocated in i2c_hid_alloc_buffers() and freed in
i2c_hid_free_buffers():

=============================================================================
BUG kmalloc-64 (Not tainted): Poison overwritten
-----------------------------------------------------------------------------
Disabling lock debugging due to kernel taint
INFO: 0xffff880264083273-0xffff88026408329e. first byte 0x0 instead of 0x6b
INFO: Allocated in i2c_hid_alloc_buffers+0x25/0xa0 [i2c_hid] age=35793 cpu=2 pid=430
	___slab_alloc+0x41e/0x460
	__slab_alloc+0x20/0x40
	__kmalloc+0x210/0x280
	i2c_hid_alloc_buffers+0x25/0xa0 [i2c_hid]
	i2c_hid_probe+0x12f/0x5e0 [i2c_hid]
	i2c_device_probe+0x10a/0x1b0
	driver_probe_device+0x220/0x4a0
	__device_attach_driver+0x71/0xa0
	bus_for_each_drv+0x67/0xb0
	__device_attach+0xdc/0x170
	device_initial_probe+0x13/0x20
	bus_probe_device+0x92/0xa0
	device_add+0x4aa/0x670
	device_register+0x1a/0x20
	i2c_new_device+0x18e/0x230
	acpi_i2c_add_device+0x1a0/0x210
INFO: Freed in i2c_hid_free_buffers+0x16/0x60 [i2c_hid] age=7552 cpu=1 pid=1473
	__slab_free+0x221/0x330
	kfree+0x139/0x160
	i2c_hid_free_buffers+0x16/0x60 [i2c_hid]
	i2c_hid_start+0x2a9/0x2df [i2c_hid]
	mt_probe+0x160/0x22e [hid_multitouch]
	hid_device_probe+0xd7/0x150 [hid]
	driver_probe_device+0x220/0x4a0
	__driver_attach+0x84/0x90
	bus_for_each_dev+0x6c/0xc0
	driver_attach+0x1e/0x20
	bus_add_driver+0x1c3/0x280
	driver_register+0x60/0xe0
	__hid_register_driver+0x53/0x90 [hid]
	0xffffffffc004f01e
	do_one_initcall+0xb3/0x1f0
	do_init_module+0x5f/0x1d0
INFO: Slab 0xffffea0009902080 objects=20 used=20 fp=0x          (null) flags=0x17fff8000004080
INFO: Object 0xffff880264083260 @offset=4704 fp=0x          (null)
Bytes b4 ffff880264083250: 8d e6 fe ff 00 00 00 00 5a 5a 5a 5a 5a 5a 5a 5a  ........ZZZZZZZZ
Object ffff880264083260: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b  kkkkkkkkkkkkkkkk
Object ffff880264083270: 6b 6b 6b 00 00 00 00 00 00 00 00 00 00 00 00 00  kkk.............
Object ffff880264083280: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
Object ffff880264083290: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
Redzone ffff8802640832a0: bb bb bb bb bb bb bb bb                          ........
Padding ffff8802640833e0: 5a 5a 5a 5a 5a 5a 5a 5a                          ZZZZZZZZ
CPU: 1 PID: 1503 Comm: python3 Tainted: G    B           4.4.21+ FireflyTeam#10
Hardware name: ASUSTeK COMPUTER INC. UX360UA/UX360UA, BIOS UX360UA.200 05/05/2016
 0000000000000086 00000000622d48a2 ffff88026061ba38 ffffffff813f6044
 ffff880264082010 ffff880264083260 ffff88026061ba78 ffffffff811e8eab
 0000000000000008 ffff880200000001 ffff88026408329f ffff88026a007700
Call Trace:
 [<ffffffff813f6044>] dump_stack+0x63/0x8f
 [<ffffffff811e8eab>] print_trailer+0x14b/0x1f0
 [<ffffffff811e94c1>] check_bytes_and_report+0xc1/0x100
 [<ffffffff811e96c4>] check_object+0x1c4/0x240
 [<ffffffff81293fde>] ? ext4_htree_store_dirent+0x3e/0x120
 [<ffffffff811e9b44>] alloc_debug_processing+0x104/0x180
 [<ffffffff811eb7be>] ___slab_alloc+0x41e/0x460
 [<ffffffff81293fde>] ? ext4_htree_store_dirent+0x3e/0x120
 [<ffffffff8124590b>] ? __getblk_gfp+0x2b/0x60
 [<ffffffff8129b969>] ? ext4_getblk+0xa9/0x190
 [<ffffffff811eb820>] __slab_alloc+0x20/0x40
 [<ffffffff811ed320>] __kmalloc+0x210/0x280
 [<ffffffff81293fde>] ? ext4_htree_store_dirent+0x3e/0x120
 [<ffffffff812c1602>] ? ext4fs_dirhash+0xc2/0x2a0
 [<ffffffff81293fde>] ext4_htree_store_dirent+0x3e/0x120
 [<ffffffff812a4f47>] htree_dirblock_to_tree+0x187/0x1b0
 [<ffffffff812a5fd2>] ext4_htree_fill_tree+0xb2/0x2e0
 [<ffffffff811ebb7a>] ? kmem_cache_alloc_trace+0x1fa/0x220
 [<ffffffff81293e45>] ? ext4_readdir+0x775/0x8b0
 [<ffffffff81293cb1>] ext4_readdir+0x5e1/0x8b0
 [<ffffffff81221c82>] iterate_dir+0x92/0x120
 [<ffffffff81222118>] SyS_getdents+0x98/0x110
 [<ffffffff81221d10>] ? iterate_dir+0x120/0x120
 [<ffffffff818157f2>] entry_SYSCALL_64_fastpath+0x16/0x71
FIX kmalloc-64: Restoring 0xffff880264083273-0xffff88026408329e=0x6b
FIX kmalloc-64: Marking all objects used

Signed-off-by: João Paulo Rechi Vita <jprvita@endlessm.com>
Reviewed-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
0lvin referenced this issue in free-z4u/roc-rk3328-cc-official Sep 28, 2019
__gre6_xmit() pushes GRE headers before handing over to ip6_tnl_xmit()
for generic IP-in-IP processing. However it doesn't make sure that there
is enough headroom to push the header to. That can lead to the panic
cited below. (Reproducer below that).

Fix by requesting either needed_headroom if already primed, or just the
bare minimum needed for the header otherwise.

[  158.576725] kernel BUG at net/core/skbuff.c:104!
[  158.581510] invalid opcode: 0000 [FireflyTeam#1] PREEMPT SMP KASAN PTI
[  158.587174] Modules linked in: act_mirred cls_matchall ip6_gre ip6_tunnel tunnel6 gre sch_ingress vrf veth x86_pkg_temp_thermal mlx_platform nfsd e1000e leds_mlxcpld
[  158.602268] CPU: 1 PID: 16 Comm: ksoftirqd/1 Not tainted 4.17.0-rc4-net_master-custom-139 FireflyTeam#10
[  158.610938] Hardware name: Mellanox Technologies Ltd. "MSN2410-CB2F"/"SA000874", BIOS 4.6.5 03/08/2016
[  158.620426] RIP: 0010:skb_panic+0xc3/0x100
[  158.624586] RSP: 0018:ffff8801d3f27110 EFLAGS: 00010286
[  158.629882] RAX: 0000000000000082 RBX: ffff8801c02cc040 RCX: 0000000000000000
[  158.637127] RDX: 0000000000000082 RSI: dffffc0000000000 RDI: ffffed003a7e4e18
[  158.644366] RBP: ffff8801bfec8020 R08: ffffed003aabce19 R09: ffffed003aabce19
[  158.651574] R10: 000000000000000b R11: ffffed003aabce18 R12: ffff8801c364de66
[  158.658786] R13: 000000000000002c R14: 00000000000000c0 R15: ffff8801c364de68
[  158.666007] FS:  0000000000000000(0000) GS:ffff8801d5400000(0000) knlGS:0000000000000000
[  158.674212] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  158.680036] CR2: 00007f4b3702dcd0 CR3: 0000000003228002 CR4: 00000000001606e0
[  158.687228] Call Trace:
[  158.689752]  ? __gre6_xmit+0x246/0xd80 [ip6_gre]
[  158.694475]  ? __gre6_xmit+0x246/0xd80 [ip6_gre]
[  158.699141]  skb_push+0x78/0x90
[  158.702344]  __gre6_xmit+0x246/0xd80 [ip6_gre]
[  158.706872]  ip6gre_tunnel_xmit+0x3bc/0x610 [ip6_gre]
[  158.711992]  ? __gre6_xmit+0xd80/0xd80 [ip6_gre]
[  158.716668]  ? debug_check_no_locks_freed+0x210/0x210
[  158.721761]  ? print_irqtrace_events+0x120/0x120
[  158.726461]  ? sched_clock_cpu+0x18/0x210
[  158.730572]  ? sched_clock_cpu+0x18/0x210
[  158.734692]  ? cyc2ns_read_end+0x10/0x10
[  158.738705]  ? skb_network_protocol+0x76/0x200
[  158.743216]  ? netif_skb_features+0x1b2/0x550
[  158.747648]  dev_hard_start_xmit+0x137/0x770
[  158.752010]  sch_direct_xmit+0x2ef/0x5d0
[  158.755992]  ? pfifo_fast_dequeue+0x3fa/0x670
[  158.760460]  ? pfifo_fast_change_tx_queue_len+0x810/0x810
[  158.765975]  ? __lock_is_held+0xa0/0x160
[  158.770002]  __qdisc_run+0x39e/0xfc0
[  158.773673]  ? _raw_spin_unlock+0x29/0x40
[  158.777781]  ? pfifo_fast_enqueue+0x24b/0x3e0
[  158.782191]  ? sch_direct_xmit+0x5d0/0x5d0
[  158.786372]  ? pfifo_fast_dequeue+0x670/0x670
[  158.790818]  ? __dev_queue_xmit+0x172/0x1770
[  158.795195]  ? preempt_count_sub+0xf/0xd0
[  158.799313]  __dev_queue_xmit+0x410/0x1770
[  158.803512]  ? ___slab_alloc+0x605/0x930
[  158.807525]  ? ___slab_alloc+0x605/0x930
[  158.811540]  ? memcpy+0x34/0x50
[  158.814768]  ? netdev_pick_tx+0x1c0/0x1c0
[  158.818895]  ? __skb_clone+0x2fd/0x3d0
[  158.822712]  ? __copy_skb_header+0x270/0x270
[  158.827079]  ? rcu_read_lock_sched_held+0x93/0xa0
[  158.831903]  ? kmem_cache_alloc+0x344/0x4d0
[  158.836199]  ? skb_clone+0x123/0x230
[  158.839869]  ? skb_split+0x820/0x820
[  158.843521]  ? tcf_mirred+0x554/0x930 [act_mirred]
[  158.848407]  tcf_mirred+0x554/0x930 [act_mirred]
[  158.853104]  ? tcf_mirred_act_wants_ingress.part.2+0x10/0x10 [act_mirred]
[  158.860005]  ? __lock_acquire+0x706/0x26e0
[  158.864162]  ? mark_lock+0x13d/0xb40
[  158.867832]  tcf_action_exec+0xcf/0x2a0
[  158.871736]  tcf_classify+0xfa/0x340
[  158.875402]  __netif_receive_skb_core+0x8e1/0x1c60
[  158.880334]  ? nf_ingress+0x500/0x500
[  158.884059]  ? process_backlog+0x347/0x4b0
[  158.888241]  ? lock_acquire+0xd8/0x320
[  158.892050]  ? process_backlog+0x1b6/0x4b0
[  158.896228]  ? process_backlog+0xc2/0x4b0
[  158.900291]  process_backlog+0xc2/0x4b0
[  158.904210]  net_rx_action+0x5cc/0x980
[  158.908047]  ? napi_complete_done+0x2c0/0x2c0
[  158.912525]  ? rcu_read_unlock+0x80/0x80
[  158.916534]  ? __lock_is_held+0x34/0x160
[  158.920541]  __do_softirq+0x1d4/0x9d2
[  158.924308]  ? trace_event_raw_event_irq_handler_exit+0x140/0x140
[  158.930515]  run_ksoftirqd+0x1d/0x40
[  158.934152]  smpboot_thread_fn+0x32b/0x690
[  158.938299]  ? sort_range+0x20/0x20
[  158.941842]  ? preempt_count_sub+0xf/0xd0
[  158.945940]  ? schedule+0x5b/0x140
[  158.949412]  kthread+0x206/0x300
[  158.952689]  ? sort_range+0x20/0x20
[  158.956249]  ? kthread_stop+0x570/0x570
[  158.960164]  ret_from_fork+0x3a/0x50
[  158.963823] Code: 14 3e ff 8b 4b 78 55 4d 89 f9 41 56 41 55 48 c7 c7 a0 cf db 82 41 54 44 8b 44 24 2c 48 8b 54 24 30 48 8b 74 24 20 e8 16 94 13 ff <0f> 0b 48 c7 c7 60 8e 1f 85 48 83 c4 20 e8 55 ef a6 ff 89 74 24
[  158.983235] RIP: skb_panic+0xc3/0x100 RSP: ffff8801d3f27110
[  158.988935] ---[ end trace 5af56ee845aa6cc8 ]---
[  158.993641] Kernel panic - not syncing: Fatal exception in interrupt
[  159.000176] Kernel Offset: disabled
[  159.003767] ---[ end Kernel panic - not syncing: Fatal exception in interrupt ]---

Reproducer:

	ip link add h1 type veth peer name swp1
	ip link add h3 type veth peer name swp3

	ip link set dev h1 up
	ip address add 192.0.2.1/28 dev h1

	ip link add dev vh3 type vrf table 20
	ip link set dev h3 master vh3
	ip link set dev vh3 up
	ip link set dev h3 up

	ip link set dev swp3 up
	ip address add dev swp3 2001:db8:2::1/64

	ip link set dev swp1 up
	tc qdisc add dev swp1 clsact

	ip link add name gt6 type ip6gretap \
		local 2001:db8:2::1 remote 2001:db8:2::2
	ip link set dev gt6 up

	sleep 1

	tc filter add dev swp1 ingress pref 1000 matchall skip_hw \
		action mirred egress mirror dev gt6
	ping -I h1 192.0.2.2

Fixes: c12b395 ("gre: Support GRE over IPv6")
Signed-off-by: Petr Machata <petrm@mellanox.com>
Acked-by: William Tu <u9012063@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
0lvin referenced this issue in free-z4u/roc-rk3328-cc-official Sep 28, 2019
dev->needed_headroom is not primed until ip6_tnl_xmit(), so it starts
out zero. Thus the call to skb_cow_head() fails to actually make sure
there's enough headroom to push the ERSPAN headers to. That can lead to
the panic cited below. (Reproducer below that).

Fix by requesting either needed_headroom if already primed, or just the
bare minimum needed for the header otherwise.

[  190.703567] kernel BUG at net/core/skbuff.c:104!
[  190.708384] invalid opcode: 0000 [FireflyTeam#1] PREEMPT SMP KASAN PTI
[  190.714007] Modules linked in: act_mirred cls_matchall ip6_gre ip6_tunnel tunnel6 gre sch_ingress vrf veth x86_pkg_temp_thermal mlx_platform nfsd e1000e leds_mlxcpld
[  190.728975] CPU: 1 PID: 959 Comm: kworker/1:2 Not tainted 4.17.0-rc4-net_master-custom-139 FireflyTeam#10
[  190.737647] Hardware name: Mellanox Technologies Ltd. "MSN2410-CB2F"/"SA000874", BIOS 4.6.5 03/08/2016
[  190.747006] Workqueue: ipv6_addrconf addrconf_dad_work
[  190.752222] RIP: 0010:skb_panic+0xc3/0x100
[  190.756358] RSP: 0018:ffff8801d54072f0 EFLAGS: 00010282
[  190.761629] RAX: 0000000000000085 RBX: ffff8801c1a8ecc0 RCX: 0000000000000000
[  190.768830] RDX: 0000000000000085 RSI: dffffc0000000000 RDI: ffffed003aa80e54
[  190.776025] RBP: ffff8801bd1ec5a0 R08: ffffed003aabce19 R09: ffffed003aabce19
[  190.783226] R10: 0000000000000001 R11: ffffed003aabce18 R12: ffff8801bf695dbe
[  190.790418] R13: 0000000000000084 R14: 00000000000006c0 R15: ffff8801bf695dc8
[  190.797621] FS:  0000000000000000(0000) GS:ffff8801d5400000(0000) knlGS:0000000000000000
[  190.805786] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  190.811582] CR2: 000055fa929aced0 CR3: 0000000003228004 CR4: 00000000001606e0
[  190.818790] Call Trace:
[  190.821264]  <IRQ>
[  190.823314]  ? ip6erspan_tunnel_xmit+0x5e4/0x1982 [ip6_gre]
[  190.828940]  ? ip6erspan_tunnel_xmit+0x5e4/0x1982 [ip6_gre]
[  190.834562]  skb_push+0x78/0x90
[  190.837749]  ip6erspan_tunnel_xmit+0x5e4/0x1982 [ip6_gre]
[  190.843219]  ? ip6gre_tunnel_ioctl+0xd90/0xd90 [ip6_gre]
[  190.848577]  ? debug_check_no_locks_freed+0x210/0x210
[  190.853679]  ? debug_check_no_locks_freed+0x210/0x210
[  190.858783]  ? print_irqtrace_events+0x120/0x120
[  190.863451]  ? sched_clock_cpu+0x18/0x210
[  190.867496]  ? cyc2ns_read_end+0x10/0x10
[  190.871474]  ? skb_network_protocol+0x76/0x200
[  190.875977]  dev_hard_start_xmit+0x137/0x770
[  190.880317]  ? do_raw_spin_trylock+0x6d/0xa0
[  190.884624]  sch_direct_xmit+0x2ef/0x5d0
[  190.888589]  ? pfifo_fast_dequeue+0x3fa/0x670
[  190.892994]  ? pfifo_fast_change_tx_queue_len+0x810/0x810
[  190.898455]  ? __lock_is_held+0xa0/0x160
[  190.902422]  __qdisc_run+0x39e/0xfc0
[  190.906041]  ? _raw_spin_unlock+0x29/0x40
[  190.910090]  ? pfifo_fast_enqueue+0x24b/0x3e0
[  190.914501]  ? sch_direct_xmit+0x5d0/0x5d0
[  190.918658]  ? pfifo_fast_dequeue+0x670/0x670
[  190.923047]  ? __dev_queue_xmit+0x172/0x1770
[  190.927365]  ? preempt_count_sub+0xf/0xd0
[  190.931421]  __dev_queue_xmit+0x410/0x1770
[  190.935553]  ? ___slab_alloc+0x605/0x930
[  190.939524]  ? print_irqtrace_events+0x120/0x120
[  190.944186]  ? memcpy+0x34/0x50
[  190.947364]  ? netdev_pick_tx+0x1c0/0x1c0
[  190.951428]  ? __skb_clone+0x2fd/0x3d0
[  190.955218]  ? __copy_skb_header+0x270/0x270
[  190.959537]  ? rcu_read_lock_sched_held+0x93/0xa0
[  190.964282]  ? kmem_cache_alloc+0x344/0x4d0
[  190.968520]  ? cyc2ns_read_end+0x10/0x10
[  190.972495]  ? skb_clone+0x123/0x230
[  190.976112]  ? skb_split+0x820/0x820
[  190.979747]  ? tcf_mirred+0x554/0x930 [act_mirred]
[  190.984582]  tcf_mirred+0x554/0x930 [act_mirred]
[  190.989252]  ? tcf_mirred_act_wants_ingress.part.2+0x10/0x10 [act_mirred]
[  190.996109]  ? __lock_acquire+0x706/0x26e0
[  191.000239]  ? sched_clock_cpu+0x18/0x210
[  191.004294]  tcf_action_exec+0xcf/0x2a0
[  191.008179]  tcf_classify+0xfa/0x340
[  191.011794]  __netif_receive_skb_core+0x8e1/0x1c60
[  191.016630]  ? debug_check_no_locks_freed+0x210/0x210
[  191.021732]  ? nf_ingress+0x500/0x500
[  191.025458]  ? process_backlog+0x347/0x4b0
[  191.029619]  ? print_irqtrace_events+0x120/0x120
[  191.034302]  ? lock_acquire+0xd8/0x320
[  191.038089]  ? process_backlog+0x1b6/0x4b0
[  191.042246]  ? process_backlog+0xc2/0x4b0
[  191.046303]  process_backlog+0xc2/0x4b0
[  191.050189]  net_rx_action+0x5cc/0x980
[  191.053991]  ? napi_complete_done+0x2c0/0x2c0
[  191.058386]  ? mark_lock+0x13d/0xb40
[  191.062001]  ? clockevents_program_event+0x6b/0x1d0
[  191.066922]  ? print_irqtrace_events+0x120/0x120
[  191.071593]  ? __lock_is_held+0xa0/0x160
[  191.075566]  __do_softirq+0x1d4/0x9d2
[  191.079282]  ? ip6_finish_output2+0x524/0x1460
[  191.083771]  do_softirq_own_stack+0x2a/0x40
[  191.087994]  </IRQ>
[  191.090130]  do_softirq.part.13+0x38/0x40
[  191.094178]  __local_bh_enable_ip+0x135/0x190
[  191.098591]  ip6_finish_output2+0x54d/0x1460
[  191.102916]  ? ip6_forward_finish+0x2f0/0x2f0
[  191.107314]  ? ip6_mtu+0x3c/0x2c0
[  191.110674]  ? ip6_finish_output+0x2f8/0x650
[  191.114992]  ? ip6_output+0x12a/0x500
[  191.118696]  ip6_output+0x12a/0x500
[  191.122223]  ? ip6_route_dev_notify+0x5b0/0x5b0
[  191.126807]  ? ip6_finish_output+0x650/0x650
[  191.131120]  ? ip6_fragment+0x1a60/0x1a60
[  191.135182]  ? icmp6_dst_alloc+0x26e/0x470
[  191.139317]  mld_sendpack+0x672/0x830
[  191.143021]  ? igmp6_mcf_seq_next+0x2f0/0x2f0
[  191.147429]  ? __local_bh_enable_ip+0x77/0x190
[  191.151913]  ipv6_mc_dad_complete+0x47/0x90
[  191.156144]  addrconf_dad_completed+0x561/0x720
[  191.160731]  ? addrconf_rs_timer+0x3a0/0x3a0
[  191.165036]  ? mark_held_locks+0xc9/0x140
[  191.169095]  ? __local_bh_enable_ip+0x77/0x190
[  191.173570]  ? addrconf_dad_work+0x50d/0xa20
[  191.177886]  ? addrconf_dad_work+0x529/0xa20
[  191.182194]  addrconf_dad_work+0x529/0xa20
[  191.186342]  ? addrconf_dad_completed+0x720/0x720
[  191.191088]  ? __lock_is_held+0xa0/0x160
[  191.195059]  ? process_one_work+0x45d/0xe20
[  191.199302]  ? process_one_work+0x51e/0xe20
[  191.203531]  ? rcu_read_lock_sched_held+0x93/0xa0
[  191.208279]  process_one_work+0x51e/0xe20
[  191.212340]  ? pwq_dec_nr_in_flight+0x200/0x200
[  191.216912]  ? get_lock_stats+0x4b/0xf0
[  191.220788]  ? preempt_count_sub+0xf/0xd0
[  191.224844]  ? worker_thread+0x219/0x860
[  191.228823]  ? do_raw_spin_trylock+0x6d/0xa0
[  191.233142]  worker_thread+0xeb/0x860
[  191.236848]  ? process_one_work+0xe20/0xe20
[  191.241095]  kthread+0x206/0x300
[  191.244352]  ? process_one_work+0xe20/0xe20
[  191.248587]  ? kthread_stop+0x570/0x570
[  191.252459]  ret_from_fork+0x3a/0x50
[  191.256082] Code: 14 3e ff 8b 4b 78 55 4d 89 f9 41 56 41 55 48 c7 c7 a0 cf db 82 41 54 44 8b 44 24 2c 48 8b 54 24 30 48 8b 74 24 20 e8 16 94 13 ff <0f> 0b 48 c7 c7 60 8e 1f 85 48 83 c4 20 e8 55 ef a6 ff 89 74 24
[  191.275327] RIP: skb_panic+0xc3/0x100 RSP: ffff8801d54072f0
[  191.281024] ---[ end trace 7ea51094e099e006 ]---
[  191.285724] Kernel panic - not syncing: Fatal exception in interrupt
[  191.292168] Kernel Offset: disabled
[  191.295697] ---[ end Kernel panic - not syncing: Fatal exception in interrupt ]---

Reproducer:

	ip link add h1 type veth peer name swp1
	ip link add h3 type veth peer name swp3

	ip link set dev h1 up
	ip address add 192.0.2.1/28 dev h1

	ip link add dev vh3 type vrf table 20
	ip link set dev h3 master vh3
	ip link set dev vh3 up
	ip link set dev h3 up

	ip link set dev swp3 up
	ip address add dev swp3 2001:db8:2::1/64

	ip link set dev swp1 up
	tc qdisc add dev swp1 clsact

	ip link add name gt6 type ip6erspan \
		local 2001:db8:2::1 remote 2001:db8:2::2 oseq okey 123
	ip link set dev gt6 up

	sleep 1

	tc filter add dev swp1 ingress pref 1000 matchall skip_hw \
		action mirred egress mirror dev gt6
	ping -I h1 192.0.2.2

Fixes: e41c7c6 ("ip6erspan: make sure enough headroom at xmit.")
Signed-off-by: Petr Machata <petrm@mellanox.com>
Acked-by: William Tu <u9012063@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
0lvin referenced this issue in free-z4u/roc-rk3328-cc-official Sep 29, 2019
commit c952b35 upstream.

bpf/btf write_* functions need ff->ph->env.

With this missing, pipe-mode (perf record -o -)  would crash like:

Program terminated with signal SIGSEGV, Segmentation fault.

This patch assign proper ph value to ff.

Committer testing:

  (gdb) run record -o -
  Starting program: /root/bin/perf record -o -
  PERFILE2
  <SNIP start of perf.data headers>
  Thread 1 "perf" received signal SIGSEGV, Segmentation fault.
  __do_write_buf (size=4, buf=0x160, ff=0x7fffffff8f80) at util/header.c:126
  126		memcpy(ff->buf + ff->offset, buf, size);
  (gdb) bt
  #0  __do_write_buf (size=4, buf=0x160, ff=0x7fffffff8f80) at util/header.c:126
  FireflyTeam#1  do_write (ff=ff@entry=0x7fffffff8f80, buf=buf@entry=0x160, size=4) at util/header.c:137
  FireflyTeam#2  0x00000000004eddba in write_bpf_prog_info (ff=0x7fffffff8f80, evlist=<optimized out>) at util/header.c:912
  FireflyTeam#3  0x00000000004f69d7 in perf_event__synthesize_features (tool=tool@entry=0x97cc00 <record>, session=session@entry=0x7fffe9c6d010,
      evlist=0x7fffe9cae010, process=process@entry=0x4435d0 <process_synthesized_event>) at util/header.c:3695
  FireflyTeam#4  0x0000000000443c79 in record__synthesize (tail=tail@entry=false, rec=0x97cc00 <record>) at builtin-record.c:1214
  FireflyTeam#5  0x0000000000444ec9 in __cmd_record (rec=0x97cc00 <record>, argv=<optimized out>, argc=0) at builtin-record.c:1435
  FireflyTeam#6  cmd_record (argc=0, argv=<optimized out>) at builtin-record.c:2450
  FireflyTeam#7  0x00000000004ae3e9 in run_builtin (p=p@entry=0x98e058 <commands+216>, argc=argc@entry=3, argv=0x7fffffffd670) at perf.c:304
  FireflyTeam#8  0x000000000042eded in handle_internal_command (argv=<optimized out>, argc=<optimized out>) at perf.c:356
  FireflyTeam#9  run_argv (argcp=<optimized out>, argv=<optimized out>) at perf.c:400
  FireflyTeam#10 main (argc=3, argv=<optimized out>) at perf.c:522
  (gdb)

After the patch the SEGSEGV is gone.

Reported-by: David Carrillo Cisneros <davidca@fb.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: kernel-team@fb.com
Cc: stable@vger.kernel.org # v5.1+
Fixes: 606f972 ("perf bpf: Save bpf_prog_info information as headers to perf.data")
Link: http://lkml.kernel.org/r/20190620010453.4118689-1-songliubraving@fb.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
0lvin referenced this issue in free-z4u/roc-rk3328-cc-official Oct 5, 2019
Petr Machata says:

====================
Mirroring tests involving VLAN

This patchset tests mirror-to-gretap with various underlay
configurations involving VLAN netdevice in particular. Some of the tests
involve bridges as well, but tests aimed specifically at testing bridges
(i.e. FDB, STP) are not part of this patchset.

In patches FireflyTeam#1-FireflyTeam#6, the codebase is adapted to support the new tests.

In patch FireflyTeam#7, a test for mirroring to VLAN is introduced.

Patches FireflyTeam#8-FireflyTeam#10 add three tests where VLAN is part of underlay path after
gretap encapsulation.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
0lvin referenced this issue in free-z4u/roc-rk3328-cc-official Oct 5, 2019
syzbot hit the following crash on upstream commit
83beed7 (Fri Apr 20 17:56:32 2018 +0000)
Merge branch 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/evalenti/linux-soc-thermal
syzbot dashboard link: https://syzkaller.appspot.com/bug?extid=d154ec99402c6f628887

C reproducer: https://syzkaller.appspot.com/x/repro.c?id=5414336294027264
syzkaller reproducer: https://syzkaller.appspot.com/x/repro.syz?id=5471683234234368
Raw console output: https://syzkaller.appspot.com/x/log.txt?id=5436660795834368
Kernel config: https://syzkaller.appspot.com/x/.config?id=1808800213120130118
compiler: gcc (GCC) 8.0.1 20180413 (experimental)

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+d154ec99402c6f628887@syzkaller.appspotmail.com
It will help syzbot understand when the bug is fixed. See footer for details.
If you forward the report, please keep this part and the footer.

F2FS-fs (loop0): Magic Mismatch, valid(0xf2f52010) - read(0x0)
F2FS-fs (loop0): Can't find valid F2FS filesystem in 1th superblock
F2FS-fs (loop0): invalid crc value
------------[ cut here ]------------
kernel BUG at fs/f2fs/node.c:1185!
invalid opcode: 0000 [FireflyTeam#1] SMP KASAN
Dumping ftrace buffer:
   (ftrace buffer empty)
Modules linked in:
CPU: 1 PID: 4549 Comm: syzkaller704305 Not tainted 4.17.0-rc1+ FireflyTeam#10
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:__get_node_page+0xb68/0x16e0 fs/f2fs/node.c:1185
RSP: 0018:ffff8801d960e820 EFLAGS: 00010293
RAX: ffff8801d88205c0 RBX: 0000000000000003 RCX: ffffffff82f6cc06
RDX: 0000000000000000 RSI: ffffffff82f6d5e8 RDI: 0000000000000004
RBP: ffff8801d960ec30 R08: ffff8801d88205c0 R09: ffffed003b5e46c2
R10: 0000000000000003 R11: 0000000000000003 R12: ffff8801a86e00c0
R13: 0000000000000001 R14: ffff8801a86e0530 R15: ffff8801d9745240
FS:  000000000072c880(0000) GS:ffff8801daf00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f3d403209b8 CR3: 00000001d8f3f000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 get_node_page fs/f2fs/node.c:1237 [inline]
 truncate_xattr_node+0x152/0x2e0 fs/f2fs/node.c:1014
 remove_inode_page+0x200/0xaf0 fs/f2fs/node.c:1039
 f2fs_evict_inode+0xe86/0x1710 fs/f2fs/inode.c:547
 evict+0x4a6/0x960 fs/inode.c:557
 iput_final fs/inode.c:1519 [inline]
 iput+0x62d/0xa80 fs/inode.c:1545
 f2fs_fill_super+0x5f4e/0x7bf0 fs/f2fs/super.c:2849
 mount_bdev+0x30c/0x3e0 fs/super.c:1164
 f2fs_mount+0x34/0x40 fs/f2fs/super.c:3020
 mount_fs+0xae/0x328 fs/super.c:1267
 vfs_kern_mount.part.34+0xd4/0x4d0 fs/namespace.c:1037
 vfs_kern_mount fs/namespace.c:1027 [inline]
 do_new_mount fs/namespace.c:2518 [inline]
 do_mount+0x564/0x3070 fs/namespace.c:2848
 ksys_mount+0x12d/0x140 fs/namespace.c:3064
 __do_sys_mount fs/namespace.c:3078 [inline]
 __se_sys_mount fs/namespace.c:3075 [inline]
 __x64_sys_mount+0xbe/0x150 fs/namespace.c:3075
 do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x443dea
RSP: 002b:00007ffcc7882368 EFLAGS: 00000297 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 0000000020000c00 RCX: 0000000000443dea
RDX: 0000000020000000 RSI: 0000000020000100 RDI: 00007ffcc7882370
RBP: 0000000000000003 R08: 0000000020016a00 R09: 000000000000000a
R10: 0000000000000000 R11: 0000000000000297 R12: 0000000000000004
R13: 0000000000402ce0 R14: 0000000000000000 R15: 0000000000000000
RIP: __get_node_page+0xb68/0x16e0 fs/f2fs/node.c:1185 RSP: ffff8801d960e820
---[ end trace 4edbeb71f002bb76 ]---

Reported-and-tested-by: syzbot+d154ec99402c6f628887@syzkaller.appspotmail.com
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
0lvin referenced this issue in free-z4u/roc-rk3328-cc-official Oct 5, 2019
This patch enhances sanity check for SIT entries.

syzbot hit the following crash on upstream commit
83beed7 (Fri Apr 20 17:56:32 2018 +0000)
Merge branch 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/evalenti/linux-soc-thermal
syzbot dashboard link: https://syzkaller.appspot.com/bug?extid=bf9253040425feb155ad

syzkaller reproducer: https://syzkaller.appspot.com/x/repro.syz?id=5692130282438656
Raw console output: https://syzkaller.appspot.com/x/log.txt?id=5095924598571008
Kernel config: https://syzkaller.appspot.com/x/.config?id=1808800213120130118
compiler: gcc (GCC) 8.0.1 20180413 (experimental)

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+bf9253040425feb155ad@syzkaller.appspotmail.com
It will help syzbot understand when the bug is fixed. See footer for details.
If you forward the report, please keep this part and the footer.

F2FS-fs (loop0): invalid crc value
F2FS-fs (loop0): Try to recover 1th superblock, ret: 0
F2FS-fs (loop0): Mounted with checkpoint version = d
F2FS-fs (loop0): Bitmap was wrongly cleared, blk:9740
------------[ cut here ]------------
kernel BUG at fs/f2fs/segment.c:1884!
invalid opcode: 0000 [FireflyTeam#1] SMP KASAN
Dumping ftrace buffer:
   (ftrace buffer empty)
Modules linked in:
CPU: 1 PID: 4508 Comm: syz-executor0 Not tainted 4.17.0-rc1+ FireflyTeam#10
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:update_sit_entry+0x1215/0x1590 fs/f2fs/segment.c:1882
RSP: 0018:ffff8801af526708 EFLAGS: 00010282
RAX: ffffed0035ea4cc0 RBX: ffff8801ad454f90 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff82eeb87e RDI: ffffed0035ea4cb6
RBP: ffff8801af526760 R08: ffff8801ad4a2480 R09: ffffed003b5e4f90
R10: ffffed003b5e4f90 R11: ffff8801daf27c87 R12: ffff8801adb8d380
R13: 0000000000000001 R14: 0000000000000008 R15: 00000000ffffffff
FS:  00000000014af940(0000) GS:ffff8801daf00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f06bc223000 CR3: 00000001adb02000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 allocate_data_block+0x66f/0x2050 fs/f2fs/segment.c:2663
 do_write_page+0x105/0x1b0 fs/f2fs/segment.c:2727
 write_node_page+0x129/0x350 fs/f2fs/segment.c:2770
 __write_node_page+0x7da/0x1370 fs/f2fs/node.c:1398
 sync_node_pages+0x18cf/0x1eb0 fs/f2fs/node.c:1652
 block_operations+0x429/0xa60 fs/f2fs/checkpoint.c:1088
 write_checkpoint+0x3ba/0x5380 fs/f2fs/checkpoint.c:1405
 f2fs_sync_fs+0x2fb/0x6a0 fs/f2fs/super.c:1077
 __sync_filesystem fs/sync.c:39 [inline]
 sync_filesystem+0x265/0x310 fs/sync.c:67
 generic_shutdown_super+0xd7/0x520 fs/super.c:429
 kill_block_super+0xa4/0x100 fs/super.c:1191
 kill_f2fs_super+0x9f/0xd0 fs/f2fs/super.c:3030
 deactivate_locked_super+0x97/0x100 fs/super.c:316
 deactivate_super+0x188/0x1b0 fs/super.c:347
 cleanup_mnt+0xbf/0x160 fs/namespace.c:1174
 __cleanup_mnt+0x16/0x20 fs/namespace.c:1181
 task_work_run+0x1e4/0x290 kernel/task_work.c:113
 tracehook_notify_resume include/linux/tracehook.h:191 [inline]
 exit_to_usermode_loop+0x2bd/0x310 arch/x86/entry/common.c:166
 prepare_exit_to_usermode arch/x86/entry/common.c:196 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:265 [inline]
 do_syscall_64+0x6ac/0x800 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x457d97
RSP: 002b:00007ffd46f9c8e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000457d97
RDX: 00000000014b09a3 RSI: 0000000000000002 RDI: 00007ffd46f9da50
RBP: 00007ffd46f9da50 R08: 0000000000000000 R09: 0000000000000009
R10: 0000000000000005 R11: 0000000000000246 R12: 00000000014b0940
R13: 0000000000000000 R14: 0000000000000002 R15: 000000000000658e
RIP: update_sit_entry+0x1215/0x1590 fs/f2fs/segment.c:1882 RSP: ffff8801af526708
---[ end trace f498328bb02610a2 ]---

Reported-and-tested-by: syzbot+bf9253040425feb155ad@syzkaller.appspotmail.com
Reported-and-tested-by: syzbot+7d6d31d3bc702f566ce3@syzkaller.appspotmail.com
Reported-and-tested-by: syzbot+0a725420475916460f12@syzkaller.appspotmail.com
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
0lvin referenced this issue in free-z4u/roc-rk3328-cc-official Oct 5, 2019
Crash dump shows following instructions

crash> bt
PID: 0      TASK: ffffffffbe412480  CPU: 0   COMMAND: "swapper/0"
 #0 [ffff891ee0003868] machine_kexec at ffffffffbd063ef1
 FireflyTeam#1 [ffff891ee00038c8] __crash_kexec at ffffffffbd12b6f2
 FireflyTeam#2 [ffff891ee0003998] crash_kexec at ffffffffbd12c84c
 FireflyTeam#3 [ffff891ee00039b8] oops_end at ffffffffbd030f0a
 FireflyTeam#4 [ffff891ee00039e0] no_context at ffffffffbd074643
 FireflyTeam#5 [ffff891ee0003a40] __bad_area_nosemaphore at ffffffffbd07496e
 FireflyTeam#6 [ffff891ee0003a90] bad_area_nosemaphore at ffffffffbd074a64
 FireflyTeam#7 [ffff891ee0003aa0] __do_page_fault at ffffffffbd074b0a
 FireflyTeam#8 [ffff891ee0003b18] do_page_fault at ffffffffbd074fc8
 FireflyTeam#9 [ffff891ee0003b50] page_fault at ffffffffbda01925
    [exception RIP: qlt_schedule_sess_for_deletion+15]
    RIP: ffffffffc02e526f  RSP: ffff891ee0003c08  RFLAGS: 00010046
    RAX: 0000000000000000  RBX: 0000000000000000  RCX: ffffffffc0307847
    RDX: 00000000000020e6  RSI: ffff891edbc377c8  RDI: 0000000000000000
    RBP: ffff891ee0003c18   R8: ffffffffc02f0b20   R9: 0000000000000250
    R10: 0000000000000258  R11: 000000000000b780  R12: ffff891ed9b43000
    R13: 00000000000000f0  R14: 0000000000000006  R15: ffff891edbc377c8
    ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0018
 FireflyTeam#10 [ffff891ee0003c20] qla2x00_fcport_event_handler at ffffffffc02853d3 [qla2xxx]
 FireflyTeam#11 [ffff891ee0003cf0] __dta_qla24xx_async_gnl_sp_done_333 at ffffffffc0285a1d [qla2xxx]
 FireflyTeam#12 [ffff891ee0003de8] qla24xx_process_response_queue at ffffffffc02a2eb5 [qla2xxx]
 FireflyTeam#13 [ffff891ee0003e88] qla24xx_msix_rsp_q at ffffffffc02a5403 [qla2xxx]
 FireflyTeam#14 [ffff891ee0003ec0] __handle_irq_event_percpu at ffffffffbd0f4c59
 FireflyTeam#15 [ffff891ee0003f10] handle_irq_event_percpu at ffffffffbd0f4e02
 FireflyTeam#16 [ffff891ee0003f40] handle_irq_event at ffffffffbd0f4e90
 rockchip-linux#17 [ffff891ee0003f68] handle_edge_irq at ffffffffbd0f8984
 rockchip-linux#18 [ffff891ee0003f88] handle_irq at ffffffffbd0305d5
 rockchip-linux#19 [ffff891ee0003fb8] do_IRQ at ffffffffbda02a18
 --- <IRQ stack> ---
 rockchip-linux#20 [ffffffffbe403d30] ret_from_intr at ffffffffbda0094e
    [exception RIP: unknown or invalid address]
    RIP: 000000000000001f  RSP: 0000000000000000  RFLAGS: fff3b8c2091ebb3f
    RAX: ffffbba5a0000200  RBX: 0000be8cdfa8f9fa  RCX: 0000000000000018
    RDX: 0000000000000101  RSI: 000000000000015d  RDI: 0000000000000193
    RBP: 0000000000000083   R8: ffffffffbe403e38   R9: 0000000000000002
    R10: 0000000000000000  R11: ffffffffbe56b820  R12: ffff891ee001cf00
    R13: ffffffffbd11c0a4  R14: ffffffffbe403d60  R15: 0000000000000001
    ORIG_RAX: ffff891ee0022ac0  CS: 0000  SS: ffffffffffffffb9
 bt: WARNING: possibly bogus exception frame
 rockchip-linux#21 [ffffffffbe403dd8] cpuidle_enter_state at ffffffffbd67c6fd
 rockchip-linux#22 [ffffffffbe403e40] cpuidle_enter at ffffffffbd67c907
 rockchip-linux#23 [ffffffffbe403e50] call_cpuidle at ffffffffbd0d98f3
 rockchip-linux#24 [ffffffffbe403e60] do_idle at ffffffffbd0d9b42
 rockchip-linux#25 [ffffffffbe403e98] cpu_startup_entry at ffffffffbd0d9da3
 rockchip-linux#26 [ffffffffbe403ec0] rest_init at ffffffffbd81d4aa
 rockchip-linux#27 [ffffffffbe403ed0] start_kernel at ffffffffbe67d2ca
 rockchip-linux#28 [ffffffffbe403f28] x86_64_start_reservations at ffffffffbe67c675
 rockchip-linux#29 [ffffffffbe403f38] x86_64_start_kernel at ffffffffbe67c6eb
 rockchip-linux#30 [ffffffffbe403f50] secondary_startup_64 at ffffffffbd0000d5

Fixes: 040036b ("scsi: qla2xxx: Delay loop id allocation at login")
Cc: <stable@vger.kernel.org> # v4.17+
Signed-off-by: Chuck Anderson <chuck.anderson@oracle.com>
Signed-off-by: Himanshu Madhani <himanshu.madhani@cavium.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
0lvin referenced this issue in free-z4u/roc-rk3328-cc-official Oct 5, 2019
In the code path where only rcu read lock is held, e.g. in the route
lookup code path, it is not safe to directly call fib6_info_hold()
because the fib6_info may already have been deleted but still exists
in the rcu grace period. Holding reference to it could cause double
free and crash the kernel.

This patch adds a new function fib6_info_hold_safe() and replace
fib6_info_hold() in all necessary places.

Syzbot reported 3 crash traces because of this. One of them is:
8021q: adding VLAN 0 to HW filter on device team0
IPv6: ADDRCONF(NETDEV_CHANGE): team0: link becomes ready
dst_release: dst:(____ptrval____) refcnt:-1
dst_release: dst:(____ptrval____) refcnt:-2
WARNING: CPU: 1 PID: 4845 at include/net/dst.h:239 dst_hold include/net/dst.h:239 [inline]
WARNING: CPU: 1 PID: 4845 at include/net/dst.h:239 ip6_setup_cork+0xd66/0x1830 net/ipv6/ip6_output.c:1204
dst_release: dst:(____ptrval____) refcnt:-1
Kernel panic - not syncing: panic_on_warn set ...

CPU: 1 PID: 4845 Comm: syz-executor493 Not tainted 4.18.0-rc3+ FireflyTeam#10
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1c9/0x2b4 lib/dump_stack.c:113
 panic+0x238/0x4e7 kernel/panic.c:184
dst_release: dst:(____ptrval____) refcnt:-2
dst_release: dst:(____ptrval____) refcnt:-3
 __warn.cold.8+0x163/0x1ba kernel/panic.c:536
dst_release: dst:(____ptrval____) refcnt:-4
 report_bug+0x252/0x2d0 lib/bug.c:186
 fixup_bug arch/x86/kernel/traps.c:178 [inline]
 do_error_trap+0x1fc/0x4d0 arch/x86/kernel/traps.c:296
dst_release: dst:(____ptrval____) refcnt:-5
 do_invalid_op+0x1b/0x20 arch/x86/kernel/traps.c:316
 invalid_op+0x14/0x20 arch/x86/entry/entry_64.S:992
RIP: 0010:dst_hold include/net/dst.h:239 [inline]
RIP: 0010:ip6_setup_cork+0xd66/0x1830 net/ipv6/ip6_output.c:1204
Code: c1 ed 03 89 9d 18 ff ff ff 48 b8 00 00 00 00 00 fc ff df 41 c6 44 05 00 f8 e9 2d 01 00 00 4c 8b a5 c8 fe ff ff e8 1a f6 e6 fa <0f> 0b e9 6a fc ff ff e8 0e f6 e6 fa 48 8b 85 d0 fe ff ff 48 8d 78
RSP: 0018:ffff8801a8fcf178 EFLAGS: 00010293
RAX: ffff8801a8eba5c0 RBX: 0000000000000000 RCX: ffffffff869511e6
RDX: 0000000000000000 RSI: ffffffff869515b6 RDI: 0000000000000005
RBP: ffff8801a8fcf2c8 R08: ffff8801a8eba5c0 R09: ffffed0035ac8338
R10: ffffed0035ac8338 R11: ffff8801ad6419c3 R12: ffff8801a8fcf720
R13: ffff8801a8fcf6a0 R14: ffff8801ad6419c0 R15: ffff8801ad641980
 ip6_make_skb+0x2c8/0x600 net/ipv6/ip6_output.c:1768
 udpv6_sendmsg+0x2c90/0x35f0 net/ipv6/udp.c:1376
 inet_sendmsg+0x1a1/0x690 net/ipv4/af_inet.c:798
 sock_sendmsg_nosec net/socket.c:641 [inline]
 sock_sendmsg+0xd5/0x120 net/socket.c:651
 ___sys_sendmsg+0x51d/0x930 net/socket.c:2125
 __sys_sendmmsg+0x240/0x6f0 net/socket.c:2220
 __do_sys_sendmmsg net/socket.c:2249 [inline]
 __se_sys_sendmmsg net/socket.c:2246 [inline]
 __x64_sys_sendmmsg+0x9d/0x100 net/socket.c:2246
 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x446ba9
Code: e8 cc bb 02 00 48 83 c4 18 c3 0f 1f 80 00 00 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 eb 08 fc ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007fb39a469da8 EFLAGS: 00000246 ORIG_RAX: 0000000000000133
RAX: ffffffffffffffda RBX: 00000000006dcc54 RCX: 0000000000446ba9
RDX: 00000000000000b8 RSI: 0000000020001b00 RDI: 0000000000000003
RBP: 00000000006dcc50 R08: 00007fb39a46a700 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 45c828efc7a64843
R13: e6eeb815b9d8a477 R14: 5068caf6f713c6fc R15: 0000000000000001
Dumping ftrace buffer:
   (ftrace buffer empty)
Kernel Offset: disabled
Rebooting in 86400 seconds..

Fixes: 93531c6 ("net/ipv6: separate handling of FIB entries from dst based routes")
Reported-by: syzbot+902e2a1bcd4f7808cef5@syzkaller.appspotmail.com
Reported-by: syzbot+8ae62d67f647abeeceb9@syzkaller.appspotmail.com
Reported-by: syzbot+3f08feb14086930677d0@syzkaller.appspotmail.com
Signed-off-by: Wei Wang <weiwan@google.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
0lvin referenced this issue in free-z4u/roc-rk3328-cc-official Oct 11, 2019
We occasionaly hit following assert failure in 'perf top', when processing the
/proc info in multiple threads.

  perf: ...include/linux/refcount.h:109: refcount_inc:
        Assertion `!(!refcount_inc_not_zero(r))' failed.

The gdb backtrace looks like this:

  [Switching to Thread 0x7ffff11ba700 (LWP 13749)]
  0x00007ffff50839fb in raise () from /lib64/libc.so.6
  (gdb)
  #0  0x00007ffff50839fb in raise () from /lib64/libc.so.6
  FireflyTeam#1  0x00007ffff5085800 in abort () from /lib64/libc.so.6
  FireflyTeam#2  0x00007ffff507c0da in __assert_fail_base () from /lib64/libc.so.6
  FireflyTeam#3  0x00007ffff507c152 in __assert_fail () from /lib64/libc.so.6
  FireflyTeam#4  0x0000000000535373 in refcount_inc (r=0x7fffdc009be0)
      at ...include/linux/refcount.h:109
  FireflyTeam#5  0x00000000005354f1 in comm_str__get (cs=0x7fffdc009bc0)
      at util/comm.c:24
  FireflyTeam#6  0x00000000005356bd in __comm_str__findnew (str=0x7fffd000b260 ":2",
      root=0xbed5c0 <comm_str_root>) at util/comm.c:72
  FireflyTeam#7  0x000000000053579e in comm_str__findnew (str=0x7fffd000b260 ":2",
      root=0xbed5c0 <comm_str_root>) at util/comm.c:95
  FireflyTeam#8  0x000000000053582e in comm__new (str=0x7fffd000b260 ":2",
      timestamp=0, exec=false) at util/comm.c:111
  FireflyTeam#9  0x00000000005363bc in thread__new (pid=2, tid=2) at util/thread.c:57
  FireflyTeam#10 0x0000000000523da0 in ____machine__findnew_thread (machine=0xbfde38,
      threads=0xbfdf28, pid=2, tid=2, create=true) at util/machine.c:457
  FireflyTeam#11 0x0000000000523eb4 in __machine__findnew_thread (machine=0xbfde38,
  ...

The failing assertion is this one:

  REFCOUNT_WARN(!refcount_inc_not_zero(r), ...

The problem is that we keep global comm_str_root list, which
is accessed by multiple threads during the 'perf top' startup
and following 2 paths can race:

  thread 1:
    ...
    thread__new
      comm__new
        comm_str__findnew
          down_write(&comm_str_lock);
          __comm_str__findnew
            comm_str__get

  thread 2:
    ...
    comm__override or comm__free
      comm_str__put
        refcount_dec_and_test
          down_write(&comm_str_lock);
          rb_erase(&cs->rb_node, &comm_str_root);

Because thread 2 first decrements the refcnt and only after then it removes the
struct comm_str from the list, the thread 1 can find this object on the list
with refcnt equls to 0 and hit the assert.

This patch fixes the thread 1 __comm_str__findnew path, by ignoring objects
that already dropped the refcnt to 0. For the rest of the objects we take the
refcnt before comparing its name and release it afterwards with comm_str__put,
which can also release the object completely.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Lukasz Odzioba <lukasz.odzioba@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Wang Nan <wangnan0@huawei.com>
Cc: kernel-team@lge.com
Link: http://lkml.kernel.org/r/20180720101740.GA27176@krava
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
rkchrome pushed a commit that referenced this issue Oct 29, 2019
commit cf3591e upstream.

Revert the commit bd293d0. The proper
fix has been made available with commit d0a255e ("loop: set
PF_MEMALLOC_NOIO for the worker thread").

Note that the fix offered by commit bd293d0 doesn't really prevent
the deadlock from occuring - if we look at the stacktrace reported by
Junxiao Bi, we see that it hangs in bit_wait_io and not on the mutex -
i.e. it has already successfully taken the mutex. Changing the mutex
from mutex_lock to mutex_trylock won't help with deadlocks that happen
afterwards.

PID: 474    TASK: ffff8813e11f4600  CPU: 10  COMMAND: "kswapd0"
   #0 [ffff8813dedfb938] __schedule at ffffffff8173f405
   #1 [ffff8813dedfb990] schedule at ffffffff8173fa27
   #2 [ffff8813dedfb9b0] schedule_timeout at ffffffff81742fec
   #3 [ffff8813dedfba60] io_schedule_timeout at ffffffff8173f186
   #4 [ffff8813dedfbaa0] bit_wait_io at ffffffff8174034f
   #5 [ffff8813dedfbac0] __wait_on_bit at ffffffff8173fec8
   #6 [ffff8813dedfbb10] out_of_line_wait_on_bit at ffffffff8173ff81
   #7 [ffff8813dedfbb90] __make_buffer_clean at ffffffffa038736f [dm_bufio]
   #8 [ffff8813dedfbbb0] __try_evict_buffer at ffffffffa0387bb8 [dm_bufio]
   #9 [ffff8813dedfbbd0] dm_bufio_shrink_scan at ffffffffa0387cc3 [dm_bufio]
  #10 [ffff8813dedfbc40] shrink_slab at ffffffff811a87ce
  #11 [ffff8813dedfbd30] shrink_zone at ffffffff811ad778
  #12 [ffff8813dedfbdc0] kswapd at ffffffff811ae92f
  #13 [ffff8813dedfbec0] kthread at ffffffff810a8428
  #14 [ffff8813dedfbf50] ret_from_fork at ffffffff81745242

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Cc: stable@vger.kernel.org
Fixes: bd293d0 ("dm bufio: fix deadlock with loop device")
Depends-on: d0a255e ("loop: set PF_MEMALLOC_NOIO for the worker thread")
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
friendlyarm pushed a commit to friendlyarm/kernel-rockchip that referenced this issue Feb 26, 2020
[ Upstream commit c194839 ]

free_match_list could be called when the flow table is already
locked. We need to pass this notation to tree_put_node.

It fixes the following lockdep warnning:

[ 1797.268537] ============================================
[ 1797.276837] WARNING: possible recursive locking detected
[ 1797.285101] 5.5.0-rc5+ rockchip-linux#10 Not tainted
[ 1797.291641] --------------------------------------------
[ 1797.299917] handler10/9296 is trying to acquire lock:
[ 1797.307885] ffff889ad399a0a0 (&node->lock){++++}, at:
tree_put_node+0x1d5/0x210 [mlx5_core]
[ 1797.319694]
[ 1797.319694] but task is already holding lock:
[ 1797.330904] ffff889ad399a0a0 (&node->lock){++++}, at:
nested_down_write_ref_node.part.33+0x1a/0x60 [mlx5_core]
[ 1797.344707]
[ 1797.344707] other info that might help us debug this:
[ 1797.356952]  Possible unsafe locking scenario:
[ 1797.356952]
[ 1797.368333]        CPU0
[ 1797.373357]        ----
[ 1797.378364]   lock(&node->lock);
[ 1797.384222]   lock(&node->lock);
[ 1797.390031]
[ 1797.390031]  *** DEADLOCK ***
[ 1797.390031]
[ 1797.403003]  May be due to missing lock nesting notation
[ 1797.403003]
[ 1797.414691] 3 locks held by handler10/9296:
[ 1797.421465]  #0: ffff889cf2c5a110 (&block->cb_lock){++++}, at:
tc_setup_cb_add+0x70/0x250
[ 1797.432810]  #1: ffff88a030081490 (&comp->sem){++++}, at:
mlx5_devcom_get_peer_data+0x4c/0xb0 [mlx5_core]
[ 1797.445829]  #2: ffff889ad399a0a0 (&node->lock){++++}, at:
nested_down_write_ref_node.part.33+0x1a/0x60 [mlx5_core]
[ 1797.459913]
[ 1797.459913] stack backtrace:
[ 1797.469436] CPU: 1 PID: 9296 Comm: handler10 Kdump: loaded Not
tainted 5.5.0-rc5+ rockchip-linux#10
[ 1797.480643] Hardware name: Dell Inc. PowerEdge R730/072T6D, BIOS
2.4.3 01/17/2017
[ 1797.491480] Call Trace:
[ 1797.496701]  dump_stack+0x96/0xe0
[ 1797.502864]  __lock_acquire.cold.63+0xf8/0x212
[ 1797.510301]  ? lockdep_hardirqs_on+0x250/0x250
[ 1797.517701]  ? mark_held_locks+0x55/0xa0
[ 1797.524547]  ? quarantine_put+0xb7/0x160
[ 1797.531422]  ? lockdep_hardirqs_on+0x17d/0x250
[ 1797.538913]  lock_acquire+0xd6/0x1f0
[ 1797.545529]  ? tree_put_node+0x1d5/0x210 [mlx5_core]
[ 1797.553701]  down_write+0x94/0x140
[ 1797.560206]  ? tree_put_node+0x1d5/0x210 [mlx5_core]
[ 1797.568464]  ? down_write_killable_nested+0x170/0x170
[ 1797.576925]  ? del_hw_flow_group+0xde/0x1f0 [mlx5_core]
[ 1797.585629]  tree_put_node+0x1d5/0x210 [mlx5_core]
[ 1797.593891]  ? free_match_list.part.25+0x147/0x170 [mlx5_core]
[ 1797.603389]  free_match_list.part.25+0xe0/0x170 [mlx5_core]
[ 1797.612654]  _mlx5_add_flow_rules+0x17e2/0x20b0 [mlx5_core]
[ 1797.621838]  ? lock_acquire+0xd6/0x1f0
[ 1797.629028]  ? esw_get_prio_table+0xb0/0x3e0 [mlx5_core]
[ 1797.637981]  ? alloc_insert_flow_group+0x420/0x420 [mlx5_core]
[ 1797.647459]  ? try_to_wake_up+0x4c7/0xc70
[ 1797.654881]  ? lock_downgrade+0x350/0x350
[ 1797.662271]  ? __mutex_unlock_slowpath+0xb1/0x3f0
[ 1797.670396]  ? find_held_lock+0xac/0xd0
[ 1797.677540]  ? mlx5_add_flow_rules+0xdc/0x360 [mlx5_core]
[ 1797.686467]  mlx5_add_flow_rules+0xdc/0x360 [mlx5_core]
[ 1797.695134]  ? _mlx5_add_flow_rules+0x20b0/0x20b0 [mlx5_core]
[ 1797.704270]  ? irq_exit+0xa5/0x170
[ 1797.710764]  ? retint_kernel+0x10/0x10
[ 1797.717698]  ? mlx5_eswitch_set_rule_source_port.isra.9+0x122/0x230
[mlx5_core]
[ 1797.728708]  mlx5_eswitch_add_offloaded_rule+0x465/0x6d0 [mlx5_core]
[ 1797.738713]  ? mlx5_eswitch_get_prio_range+0x30/0x30 [mlx5_core]
[ 1797.748384]  ? mlx5_fc_stats_work+0x670/0x670 [mlx5_core]
[ 1797.757400]  mlx5e_tc_offload_fdb_rules.isra.27+0x24/0x90 [mlx5_core]
[ 1797.767665]  mlx5e_tc_add_fdb_flow+0xaf8/0xd40 [mlx5_core]
[ 1797.776886]  ? mlx5e_encap_put+0xd0/0xd0 [mlx5_core]
[ 1797.785562]  ? mlx5e_alloc_flow.isra.43+0x18c/0x1c0 [mlx5_core]
[ 1797.795353]  __mlx5e_add_fdb_flow+0x2e2/0x440 [mlx5_core]
[ 1797.804558]  ? mlx5e_tc_update_neigh_used_value+0x8c0/0x8c0
[mlx5_core]
[ 1797.815093]  ? wait_for_completion+0x260/0x260
[ 1797.823272]  mlx5e_configure_flower+0xe94/0x1620 [mlx5_core]
[ 1797.832792]  ? __mlx5e_add_fdb_flow+0x440/0x440 [mlx5_core]
[ 1797.842096]  ? down_read+0x11a/0x2e0
[ 1797.849090]  ? down_write+0x140/0x140
[ 1797.856142]  ? mlx5e_rep_indr_setup_block_cb+0xc0/0xc0 [mlx5_core]
[ 1797.866027]  tc_setup_cb_add+0x11a/0x250
[ 1797.873339]  fl_hw_replace_filter+0x25e/0x320 [cls_flower]
[ 1797.882385]  ? fl_hw_destroy_filter+0x1c0/0x1c0 [cls_flower]
[ 1797.891607]  fl_change+0x1d54/0x1fb6 [cls_flower]
[ 1797.899772]  ? __rhashtable_insert_fast.constprop.50+0x9f0/0x9f0
[cls_flower]
[ 1797.910728]  ? lock_downgrade+0x350/0x350
[ 1797.918187]  ? __radix_tree_lookup+0xa5/0x130
[ 1797.926046]  ? fl_set_key+0x1590/0x1590 [cls_flower]
[ 1797.934611]  ? __rhashtable_insert_fast.constprop.50+0x9f0/0x9f0
[cls_flower]
[ 1797.945673]  tc_new_tfilter+0xcd1/0x1240
[ 1797.953138]  ? tc_del_tfilter+0xb10/0xb10
[ 1797.960688]  ? avc_has_perm_noaudit+0x92/0x320
[ 1797.968721]  ? avc_has_perm_noaudit+0x1df/0x320
[ 1797.976816]  ? avc_has_extended_perms+0x990/0x990
[ 1797.985090]  ? mark_lock+0xaa/0x9e0
[ 1797.991988]  ? match_held_lock+0x1b/0x240
[ 1797.999457]  ? match_held_lock+0x1b/0x240
[ 1798.006859]  ? find_held_lock+0xac/0xd0
[ 1798.014045]  ? symbol_put_addr+0x40/0x40
[ 1798.021317]  ? rcu_read_lock_sched_held+0xd0/0xd0
[ 1798.029460]  ? tc_del_tfilter+0xb10/0xb10
[ 1798.036810]  rtnetlink_rcv_msg+0x4d5/0x620
[ 1798.044236]  ? rtnl_bridge_getlink+0x460/0x460
[ 1798.052034]  ? lockdep_hardirqs_on+0x250/0x250
[ 1798.059837]  ? match_held_lock+0x1b/0x240
[ 1798.067146]  ? find_held_lock+0xac/0xd0
[ 1798.074246]  netlink_rcv_skb+0xc6/0x1f0
[ 1798.081339]  ? rtnl_bridge_getlink+0x460/0x460
[ 1798.089104]  ? netlink_ack+0x440/0x440
[ 1798.096061]  netlink_unicast+0x2d4/0x3b0
[ 1798.103189]  ? netlink_attachskb+0x3f0/0x3f0
[ 1798.110724]  ? _copy_from_iter_full+0xda/0x370
[ 1798.118415]  netlink_sendmsg+0x3ba/0x6a0
[ 1798.125478]  ? netlink_unicast+0x3b0/0x3b0
[ 1798.132705]  ? netlink_unicast+0x3b0/0x3b0
[ 1798.139880]  sock_sendmsg+0x94/0xa0
[ 1798.146332]  ____sys_sendmsg+0x36c/0x3f0
[ 1798.153251]  ? copy_msghdr_from_user+0x165/0x230
[ 1798.160941]  ? kernel_sendmsg+0x30/0x30
[ 1798.167738]  ___sys_sendmsg+0xeb/0x150
[ 1798.174411]  ? sendmsg_copy_msghdr+0x30/0x30
[ 1798.181649]  ? lock_downgrade+0x350/0x350
[ 1798.188559]  ? rcu_read_lock_sched_held+0xd0/0xd0
[ 1798.196239]  ? __fget+0x21d/0x320
[ 1798.202335]  ? do_dup2+0x2a0/0x2a0
[ 1798.208499]  ? lock_downgrade+0x350/0x350
[ 1798.215366]  ? __fget_light+0xd6/0xf0
[ 1798.221808]  ? syscall_trace_enter+0x369/0x5d0
[ 1798.229112]  __sys_sendmsg+0xd3/0x160
[ 1798.235511]  ? __sys_sendmsg_sock+0x60/0x60
[ 1798.242478]  ? syscall_trace_enter+0x233/0x5d0
[ 1798.249721]  ? syscall_slow_exit_work+0x280/0x280
[ 1798.257211]  ? do_syscall_64+0x1e/0x2e0
[ 1798.263680]  do_syscall_64+0x72/0x2e0
[ 1798.269950]  entry_SYSCALL_64_after_hwframe+0x49/0xbe

Fixes: bd71b08 ("net/mlx5: Support multiple updates of steering rules in parallel")
Signed-off-by: Maor Gottlieb <maorg@mellanox.com>
Signed-off-by: Alaa Hleihel <alaa@mellanox.com>
Reviewed-by: Mark Bloch <markb@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
friendlyarm pushed a commit to friendlyarm/kernel-rockchip that referenced this issue Apr 2, 2020
commit f767078 upstream.

There has oops as below happen on i.MX8MP EVK platform that has
6G bytes DDR memory.

when (xmit->tail < xmit->head) && (xmit->head == 0),
it setups one sg entry with sg->length is zero:
	sg_set_buf(sgl + 1, xmit->buf, xmit->head);

if xmit->buf is allocated from >4G address space, and SDMA only
support <4G address space, then dma_map_sg() will call swiotlb_map()
to do bounce buffer copying and mapping.

But swiotlb_map() don't allow sg entry's length is zero, otherwise
report BUG_ON().

So the patch is to correct the tx DMA scatter list.

Oops:
[  287.675715] kernel BUG at kernel/dma/swiotlb.c:497!
[  287.680592] Internal error: Oops - BUG: 0 [#1] PREEMPT SMP
[  287.686075] Modules linked in:
[  287.689133] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.4.3-00016-g3fdc4e0-dirty rockchip-linux#10
[  287.696872] Hardware name: FSL i.MX8MP EVK (DT)
[  287.701402] pstate: 80000085 (Nzcv daIf -PAN -UAO)
[  287.706199] pc : swiotlb_tbl_map_single+0x1fc/0x310
[  287.711076] lr : swiotlb_map+0x60/0x148
[  287.714909] sp : ffff800010003c00
[  287.718221] x29: ffff800010003c00 x28: 0000000000000000
[  287.723533] x27: 0000000000000040 x26: ffff800011ae0000
[  287.728844] x25: ffff800011ae09f8 x24: 0000000000000000
[  287.734155] x23: 00000001b7af9000 x22: 0000000000000000
[  287.739465] x21: ffff000176409c10 x20: 00000000001f7ffe
[  287.744776] x19: ffff000176409c10 x18: 000000000000002e
[  287.750087] x17: 0000000000000000 x16: 0000000000000000
[  287.755397] x15: 0000000000000000 x14: 0000000000000000
[  287.760707] x13: ffff00017f334000 x12: 0000000000000001
[  287.766018] x11: 00000000001fffff x10: 0000000000000000
[  287.771328] x9 : 0000000000000003 x8 : 0000000000000000
[  287.776638] x7 : 0000000000000000 x6 : 0000000000000000
[  287.781949] x5 : 0000000000200000 x4 : 0000000000000000
[  287.787259] x3 : 0000000000000001 x2 : 00000001b7af9000
[  287.792570] x1 : 00000000fbfff000 x0 : 0000000000000000
[  287.797881] Call trace:
[  287.800328]  swiotlb_tbl_map_single+0x1fc/0x310
[  287.804859]  swiotlb_map+0x60/0x148
[  287.808347]  dma_direct_map_page+0xf0/0x130
[  287.812530]  dma_direct_map_sg+0x78/0xe0
[  287.816453]  imx_uart_dma_tx+0x134/0x2f8
[  287.820374]  imx_uart_dma_tx_callback+0xd8/0x168
[  287.824992]  vchan_complete+0x194/0x200
[  287.828828]  tasklet_action_common.isra.0+0x154/0x1a0
[  287.833879]  tasklet_action+0x24/0x30
[  287.837540]  __do_softirq+0x120/0x23c
[  287.841202]  irq_exit+0xb8/0xd8
[  287.844343]  __handle_domain_irq+0x64/0xb8
[  287.848438]  gic_handle_irq+0x5c/0x148
[  287.852185]  el1_irq+0xb8/0x180
[  287.855327]  cpuidle_enter_state+0x84/0x360
[  287.859508]  cpuidle_enter+0x34/0x48
[  287.863083]  call_cpuidle+0x18/0x38
[  287.866571]  do_idle+0x1e0/0x280
[  287.869798]  cpu_startup_entry+0x20/0x40
[  287.873721]  rest_init+0xd4/0xe0
[  287.876949]  arch_call_rest_init+0xc/0x14
[  287.880958]  start_kernel+0x420/0x44c
[  287.884622] Code: 9124c021 9417aff8 a94363f7 17ffffd5 (d4210000)
[  287.890718] ---[ end trace 5bc44c4ab6b009ce ]---
[  287.895334] Kernel panic - not syncing: Fatal exception in interrupt
[  287.901686] SMP: stopping secondary CPUs
[  288.905607] SMP: failed to stop secondary CPUs 0-1
[  288.910395] Kernel Offset: disabled
[  288.913882] CPU features: 0x0002,2000200c
[  288.917888] Memory Limit: none
[  288.920944] ---[ end Kernel panic - not syncing: Fatal exception in interrupt ]---

Reported-by: Eagle Zhou <eagle.zhou@nxp.com>
Tested-by: Eagle Zhou <eagle.zhou@nxp.com>
Signed-off-by: Fugang Duan <fugang.duan@nxp.com>
Cc: stable <stable@vger.kernel.org>
Fixes: 7942f85 ("serial: imx: TX DMA: clean up sg initialization")
Reviewed-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/1581401761-6378-1-git-send-email-fugang.duan@nxp.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
fanck0605 pushed a commit to fanck0605/friendlywrt-kernel that referenced this issue Apr 27, 2020
[ Upstream commit 1bc7896 ]

When experimenting with bpf_send_signal() helper in our production
environment (5.2 based), we experienced a deadlock in NMI mode:
   friendlyarm#5 [ffffc9002219f770] queued_spin_lock_slowpath at ffffffff8110be24
   friendlyarm#6 [ffffc9002219f770] _raw_spin_lock_irqsave at ffffffff81a43012
   friendlyarm#7 [ffffc9002219f780] try_to_wake_up at ffffffff810e7ecd
   friendlyarm#8 [ffffc9002219f7e0] signal_wake_up_state at ffffffff810c7b55
   rockchip-linux#9 [ffffc9002219f7f0] __send_signal at ffffffff810c8602
  rockchip-linux#10 [ffffc9002219f830] do_send_sig_info at ffffffff810ca31a
  rockchip-linux#11 [ffffc9002219f868] bpf_send_signal at ffffffff8119d227
  rockchip-linux#12 [ffffc9002219f988] bpf_overflow_handler at ffffffff811d4140
  rockchip-linux#13 [ffffc9002219f9e0] __perf_event_overflow at ffffffff811d68cf
  rockchip-linux#14 [ffffc9002219fa10] perf_swevent_overflow at ffffffff811d6a09
  rockchip-linux#15 [ffffc9002219fa38] ___perf_sw_event at ffffffff811e0f47
  rockchip-linux#16 [ffffc9002219fc30] __schedule at ffffffff81a3e04d
  rockchip-linux#17 [ffffc9002219fc90] schedule at ffffffff81a3e219
  rockchip-linux#18 [ffffc9002219fca0] futex_wait_queue_me at ffffffff8113d1b9
  rockchip-linux#19 [ffffc9002219fcd8] futex_wait at ffffffff8113e529
  rockchip-linux#20 [ffffc9002219fdf0] do_futex at ffffffff8113ffbc
  rockchip-linux#21 [ffffc9002219fec0] __x64_sys_futex at ffffffff81140d1c
  rockchip-linux#22 [ffffc9002219ff38] do_syscall_64 at ffffffff81002602
  rockchip-linux#23 [ffffc9002219ff50] entry_SYSCALL_64_after_hwframe at ffffffff81c00068

The above call stack is actually very similar to an issue
reported by Commit eac9153 ("bpf/stackmap: Fix deadlock with
rq_lock in bpf_get_stack()") by Song Liu. The only difference is
bpf_send_signal() helper instead of bpf_get_stack() helper.

The above deadlock is triggered with a perf_sw_event.
Similar to Commit eac9153, the below almost identical reproducer
used tracepoint point sched/sched_switch so the issue can be easily caught.
  /* stress_test.c */
  #include <stdio.h>
  #include <stdlib.h>
  #include <sys/mman.h>
  #include <pthread.h>
  #include <sys/types.h>
  #include <sys/stat.h>
  #include <fcntl.h>

  #define THREAD_COUNT 1000
  char *filename;
  void *worker(void *p)
  {
        void *ptr;
        int fd;
        char *pptr;

        fd = open(filename, O_RDONLY);
        if (fd < 0)
                return NULL;
        while (1) {
                struct timespec ts = {0, 1000 + rand() % 2000};

                ptr = mmap(NULL, 4096 * 64, PROT_READ, MAP_PRIVATE, fd, 0);
                usleep(1);
                if (ptr == MAP_FAILED) {
                        printf("failed to mmap\n");
                        break;
                }
                munmap(ptr, 4096 * 64);
                usleep(1);
                pptr = malloc(1);
                usleep(1);
                pptr[0] = 1;
                usleep(1);
                free(pptr);
                usleep(1);
                nanosleep(&ts, NULL);
        }
        close(fd);
        return NULL;
  }

  int main(int argc, char *argv[])
  {
        void *ptr;
        int i;
        pthread_t threads[THREAD_COUNT];

        if (argc < 2)
                return 0;

        filename = argv[1];

        for (i = 0; i < THREAD_COUNT; i++) {
                if (pthread_create(threads + i, NULL, worker, NULL)) {
                        fprintf(stderr, "Error creating thread\n");
                        return 0;
                }
        }

        for (i = 0; i < THREAD_COUNT; i++)
                pthread_join(threads[i], NULL);
        return 0;
  }
and the following command:
  1. run `stress_test /bin/ls` in one windown
  2. hack bcc trace.py with the following change:
#     --- a/tools/trace.py
#     +++ b/tools/trace.py
     @@ -513,6 +513,7 @@ BPF_PERF_OUTPUT(%s);
              __data.tgid = __tgid;
              __data.pid = __pid;
              bpf_get_current_comm(&__data.comm, sizeof(__data.comm));
     +        bpf_send_signal(10);
      %s
      %s
              %s.perf_submit(%s, &__data, sizeof(__data));
  3. in a different window run
     ./trace.py -p $(pidof stress_test) t:sched:sched_switch

The deadlock can be reproduced in our production system.

Similar to Song's fix, the fix is to delay sending signal if
irqs is disabled to avoid deadlocks involving with rq_lock.
With this change, my above stress-test in our production system
won't cause deadlock any more.

I also implemented a scale-down version of reproducer in the
selftest (a subsequent commit). With latest bpf-next,
it complains for the following potential deadlock.
  [   32.832450] -> friendlyarm#1 (&p->pi_lock){-.-.}:
  [   32.833100]        _raw_spin_lock_irqsave+0x44/0x80
  [   32.833696]        task_rq_lock+0x2c/0xa0
  [   32.834182]        task_sched_runtime+0x59/0xd0
  [   32.834721]        thread_group_cputime+0x250/0x270
  [   32.835304]        thread_group_cputime_adjusted+0x2e/0x70
  [   32.835959]        do_task_stat+0x8a7/0xb80
  [   32.836461]        proc_single_show+0x51/0xb0
  ...
  [   32.839512] -> #0 (&(&sighand->siglock)->rlock){....}:
  [   32.840275]        __lock_acquire+0x1358/0x1a20
  [   32.840826]        lock_acquire+0xc7/0x1d0
  [   32.841309]        _raw_spin_lock_irqsave+0x44/0x80
  [   32.841916]        __lock_task_sighand+0x79/0x160
  [   32.842465]        do_send_sig_info+0x35/0x90
  [   32.842977]        bpf_send_signal+0xa/0x10
  [   32.843464]        bpf_prog_bc13ed9e4d3163e3_send_signal_tp_sched+0x465/0x1000
  [   32.844301]        trace_call_bpf+0x115/0x270
  [   32.844809]        perf_trace_run_bpf_submit+0x4a/0xc0
  [   32.845411]        perf_trace_sched_switch+0x10f/0x180
  [   32.846014]        __schedule+0x45d/0x880
  [   32.846483]        schedule+0x5f/0xd0
  ...

  [   32.853148] Chain exists of:
  [   32.853148]   &(&sighand->siglock)->rlock --> &p->pi_lock --> &rq->lock
  [   32.853148]
  [   32.854451]  Possible unsafe locking scenario:
  [   32.854451]
  [   32.855173]        CPU0                    CPU1
  [   32.855745]        ----                    ----
  [   32.856278]   lock(&rq->lock);
  [   32.856671]                                lock(&p->pi_lock);
  [   32.857332]                                lock(&rq->lock);
  [   32.857999]   lock(&(&sighand->siglock)->rlock);

  Deadlock happens on CPU0 when it tries to acquire &sighand->siglock
  but it has been held by CPU1 and CPU1 tries to grab &rq->lock
  and cannot get it.

  This is not exactly the callstack in our production environment,
  but sympotom is similar and both locks are using spin_lock_irqsave()
  to acquire the lock, and both involves rq_lock. The fix to delay
  sending signal when irq is disabled also fixed this issue.

Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Cc: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20200304191104.2796501-1-yhs@fb.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
friendlyarm pushed a commit to friendlyarm/kernel-rockchip that referenced this issue Aug 31, 2020
[ Upstream commit e24c644 ]

I compiled with AddressSanitizer and I had these memory leaks while I
was using the tep_parse_format function:

    Direct leak of 28 byte(s) in 4 object(s) allocated from:
        #0 0x7fb07db49ffe in __interceptor_realloc (/lib/x86_64-linux-gnu/libasan.so.5+0x10dffe)
        #1 0x7fb07a724228 in extend_token /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:985
        #2 0x7fb07a724c21 in __read_token /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:1140
        #3 0x7fb07a724f78 in read_token /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:1206
        #4 0x7fb07a725191 in __read_expect_type /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:1291
        #5 0x7fb07a7251df in read_expect_type /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:1299
        #6 0x7fb07a72e6c8 in process_dynamic_array_len /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:2849
        #7 0x7fb07a7304b8 in process_function /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:3161
        #8 0x7fb07a730900 in process_arg_token /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:3207
        rockchip-linux#9 0x7fb07a727c0b in process_arg /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:1786
        rockchip-linux#10 0x7fb07a731080 in event_read_print_args /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:3285
        rockchip-linux#11 0x7fb07a731722 in event_read_print /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:3369
        rockchip-linux#12 0x7fb07a740054 in __tep_parse_format /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:6335
        rockchip-linux#13 0x7fb07a74047a in __parse_event /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:6389
        rockchip-linux#14 0x7fb07a740536 in tep_parse_format /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:6431
        rockchip-linux#15 0x7fb07a785acf in parse_event ../../../src/fs-src/fs.c:251
        rockchip-linux#16 0x7fb07a785ccd in parse_systems ../../../src/fs-src/fs.c:284
        rockchip-linux#17 0x7fb07a786fb3 in read_metadata ../../../src/fs-src/fs.c:593
        rockchip-linux#18 0x7fb07a78760e in ftrace_fs_source_init ../../../src/fs-src/fs.c:727
        rockchip-linux#19 0x7fb07d90c19c in add_component_with_init_method_data ../../../../src/lib/graph/graph.c:1048
        rockchip-linux#20 0x7fb07d90c87b in add_source_component_with_initialize_method_data ../../../../src/lib/graph/graph.c:1127
        rockchip-linux#21 0x7fb07d90c92a in bt_graph_add_source_component ../../../../src/lib/graph/graph.c:1152
        rockchip-linux#22 0x55db11aa632e in cmd_run_ctx_create_components_from_config_components ../../../src/cli/babeltrace2.c:2252
        rockchip-linux#23 0x55db11aa6fda in cmd_run_ctx_create_components ../../../src/cli/babeltrace2.c:2347
        rockchip-linux#24 0x55db11aa780c in cmd_run ../../../src/cli/babeltrace2.c:2461
        rockchip-linux#25 0x55db11aa8a7d in main ../../../src/cli/babeltrace2.c:2673
        rockchip-linux#26 0x7fb07d5460b2 in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x270b2)

The token variable in the process_dynamic_array_len function is
allocated in the read_expect_type function, but is not freed before
calling the read_token function.

Free the token variable before calling read_token in order to plug the
leak.

Signed-off-by: Philippe Duplessis-Guindon <pduplessis@efficios.com>
Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Link: https://lore.kernel.org/linux-trace-devel/20200730150236.5392-1-pduplessis@efficios.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
AaronDewes pushed a commit to AaronDewes/kernel that referenced this issue Sep 29, 2020
[ Upstream commit d26383d ]

The following leaks were detected by ASAN:

  Indirect leak of 360 byte(s) in 9 object(s) allocated from:
    #0 0x7fecc305180e in calloc (/lib/x86_64-linux-gnu/libasan.so.5+0x10780e)
    rockchip-linux#1 0x560578f6dce5 in perf_pmu__new_format util/pmu.c:1333
    rockchip-linux#2 0x560578f752fc in perf_pmu_parse util/pmu.y:59
    rockchip-linux#3 0x560578f6a8b7 in perf_pmu__format_parse util/pmu.c:73
    rockchip-linux#4 0x560578e07045 in test__pmu tests/pmu.c:155
    rockchip-linux#5 0x560578de109b in run_test tests/builtin-test.c:410
    rockchip-linux#6 0x560578de109b in test_and_print tests/builtin-test.c:440
    rockchip-linux#7 0x560578de401a in __cmd_test tests/builtin-test.c:661
    rockchip-linux#8 0x560578de401a in cmd_test tests/builtin-test.c:807
    rockchip-linux#9 0x560578e49354 in run_builtin /home/namhyung/project/linux/tools/perf/perf.c:312
    rockchip-linux#10 0x560578ce71a8 in handle_internal_command /home/namhyung/project/linux/tools/perf/perf.c:364
    rockchip-linux#11 0x560578ce71a8 in run_argv /home/namhyung/project/linux/tools/perf/perf.c:408
    rockchip-linux#12 0x560578ce71a8 in main /home/namhyung/project/linux/tools/perf/perf.c:538
    rockchip-linux#13 0x7fecc2b7acc9 in __libc_start_main ../csu/libc-start.c:308

Fixes: cff7f95 ("perf tests: Move pmu tests into separate object")
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lore.kernel.org/lkml/20200915031819.386559-12-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Joern-P pushed a commit to Joern-P/kernel that referenced this issue Nov 10, 2020
rtk_btusb: RTKBT_RELEASE_NAME: 20200318_BT_ANDROID_9.0
rtk_btusb: Realtek Bluetooth USB driver module init, version 5.2.1
rtk_btusb: Register usb char device interface for BT driver
BUG: spinlock bad magic on CPU#0, swapper/0/1
 lock: running_flag_lock+0x0/0x38, .magic: 00000000, .owner: <none>/-1, .owner_cpu: 0
CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.4.194 rockchip-linux#10
Hardware name: Rockchip RK3399 Evaluation Board v3 (Android) (DT)
Call trace:
[<ffffff800808a8c0>] dump_backtrace+0x0/0x1f4
[<ffffff800808aac8>] show_stack+0x14/0x1c
[<ffffff8008416248>] dump_stack+0xb4/0xf4
[<ffffff800810b1c0>] spin_dump+0x70/0x8c
[<ffffff800810b204>] spin_bug+0x28/0x34
[<ffffff800810b2a0>] do_raw_spin_lock+0x34/0x158
[<ffffff8008d68650>] _raw_spin_lock+0x48/0x54
[<ffffff80093b996c>] btusb_init+0x200/0x21c
[<ffffff80080834a8>] do_one_initcall+0x84/0x1a8
[<ffffff8009380f10>] kernel_init_freeable+0x278/0x27c
[<ffffff8008d61d3c>] kernel_init+0x10/0xf8
[<ffffff80080832d0>] ret_from_fork+0x10/0x40

Fixes: 4c267a4 ("Bluetooth: rtk_btusb: update rtk_btusb to version 5.2.1")
Change-Id: I6ea6c46a5abccc5848ec6e1538c4d7109135b725
Signed-off-by: Tao Huang <huangtao@rock-chips.com>
friendlyarm pushed a commit to friendlyarm/kernel-rockchip that referenced this issue Nov 17, 2020
commit 66d204a upstream.

Very sporadically I had test case btrfs/069 from fstests hanging (for
years, it is not a recent regression), with the following traces in
dmesg/syslog:

  [162301.160628] BTRFS info (device sdc): dev_replace from /dev/sdd (devid 2) to /dev/sdg started
  [162301.181196] BTRFS info (device sdc): scrub: finished on devid 4 with status: 0
  [162301.287162] BTRFS info (device sdc): dev_replace from /dev/sdd (devid 2) to /dev/sdg finished
  [162513.513792] INFO: task btrfs-transacti:1356167 blocked for more than 120 seconds.
  [162513.514318]       Not tainted 5.9.0-rc6-btrfs-next-69 #1
  [162513.514522] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
  [162513.514747] task:btrfs-transacti state:D stack:    0 pid:1356167 ppid:     2 flags:0x00004000
  [162513.514751] Call Trace:
  [162513.514761]  __schedule+0x5ce/0xd00
  [162513.514765]  ? _raw_spin_unlock_irqrestore+0x3c/0x60
  [162513.514771]  schedule+0x46/0xf0
  [162513.514844]  wait_current_trans+0xde/0x140 [btrfs]
  [162513.514850]  ? finish_wait+0x90/0x90
  [162513.514864]  start_transaction+0x37c/0x5f0 [btrfs]
  [162513.514879]  transaction_kthread+0xa4/0x170 [btrfs]
  [162513.514891]  ? btrfs_cleanup_transaction+0x660/0x660 [btrfs]
  [162513.514894]  kthread+0x153/0x170
  [162513.514897]  ? kthread_stop+0x2c0/0x2c0
  [162513.514902]  ret_from_fork+0x22/0x30
  [162513.514916] INFO: task fsstress:1356184 blocked for more than 120 seconds.
  [162513.515192]       Not tainted 5.9.0-rc6-btrfs-next-69 #1
  [162513.515431] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
  [162513.515680] task:fsstress        state:D stack:    0 pid:1356184 ppid:1356177 flags:0x00004000
  [162513.515682] Call Trace:
  [162513.515688]  __schedule+0x5ce/0xd00
  [162513.515691]  ? _raw_spin_unlock_irqrestore+0x3c/0x60
  [162513.515697]  schedule+0x46/0xf0
  [162513.515712]  wait_current_trans+0xde/0x140 [btrfs]
  [162513.515716]  ? finish_wait+0x90/0x90
  [162513.515729]  start_transaction+0x37c/0x5f0 [btrfs]
  [162513.515743]  btrfs_attach_transaction_barrier+0x1f/0x50 [btrfs]
  [162513.515753]  btrfs_sync_fs+0x61/0x1c0 [btrfs]
  [162513.515758]  ? __ia32_sys_fdatasync+0x20/0x20
  [162513.515761]  iterate_supers+0x87/0xf0
  [162513.515765]  ksys_sync+0x60/0xb0
  [162513.515768]  __do_sys_sync+0xa/0x10
  [162513.515771]  do_syscall_64+0x33/0x80
  [162513.515774]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
  [162513.515781] RIP: 0033:0x7f5238f50bd7
  [162513.515782] Code: Bad RIP value.
  [162513.515784] RSP: 002b:00007fff67b978e8 EFLAGS: 00000206 ORIG_RAX: 00000000000000a2
  [162513.515786] RAX: ffffffffffffffda RBX: 000055b1fad2c560 RCX: 00007f5238f50bd7
  [162513.515788] RDX: 00000000ffffffff RSI: 000000000daf0e74 RDI: 000000000000003a
  [162513.515789] RBP: 0000000000000032 R08: 000000000000000a R09: 00007f5239019be0
  [162513.515791] R10: fffffffffffff24f R11: 0000000000000206 R12: 000000000000003a
  [162513.515792] R13: 00007fff67b97950 R14: 00007fff67b97906 R15: 000055b1fad1a340
  [162513.515804] INFO: task fsstress:1356185 blocked for more than 120 seconds.
  [162513.516064]       Not tainted 5.9.0-rc6-btrfs-next-69 #1
  [162513.516329] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
  [162513.516617] task:fsstress        state:D stack:    0 pid:1356185 ppid:1356177 flags:0x00000000
  [162513.516620] Call Trace:
  [162513.516625]  __schedule+0x5ce/0xd00
  [162513.516628]  ? _raw_spin_unlock_irqrestore+0x3c/0x60
  [162513.516634]  schedule+0x46/0xf0
  [162513.516647]  wait_current_trans+0xde/0x140 [btrfs]
  [162513.516650]  ? finish_wait+0x90/0x90
  [162513.516662]  start_transaction+0x4d7/0x5f0 [btrfs]
  [162513.516679]  btrfs_setxattr_trans+0x3c/0x100 [btrfs]
  [162513.516686]  __vfs_setxattr+0x66/0x80
  [162513.516691]  __vfs_setxattr_noperm+0x70/0x200
  [162513.516697]  vfs_setxattr+0x6b/0x120
  [162513.516703]  setxattr+0x125/0x240
  [162513.516709]  ? lock_acquire+0xb1/0x480
  [162513.516712]  ? mnt_want_write+0x20/0x50
  [162513.516721]  ? rcu_read_lock_any_held+0x8e/0xb0
  [162513.516723]  ? preempt_count_add+0x49/0xa0
  [162513.516725]  ? __sb_start_write+0x19b/0x290
  [162513.516727]  ? preempt_count_add+0x49/0xa0
  [162513.516732]  path_setxattr+0xba/0xd0
  [162513.516739]  __x64_sys_setxattr+0x27/0x30
  [162513.516741]  do_syscall_64+0x33/0x80
  [162513.516743]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
  [162513.516745] RIP: 0033:0x7f5238f56d5a
  [162513.516746] Code: Bad RIP value.
  [162513.516748] RSP: 002b:00007fff67b97868 EFLAGS: 00000202 ORIG_RAX: 00000000000000bc
  [162513.516750] RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 00007f5238f56d5a
  [162513.516751] RDX: 000055b1fbb0d5a0 RSI: 00007fff67b978a0 RDI: 000055b1fbb0d470
  [162513.516753] RBP: 000055b1fbb0d5a0 R08: 0000000000000001 R09: 00007fff67b97700
  [162513.516754] R10: 0000000000000004 R11: 0000000000000202 R12: 0000000000000004
  [162513.516756] R13: 0000000000000024 R14: 0000000000000001 R15: 00007fff67b978a0
  [162513.516767] INFO: task fsstress:1356196 blocked for more than 120 seconds.
  [162513.517064]       Not tainted 5.9.0-rc6-btrfs-next-69 #1
  [162513.517365] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
  [162513.517763] task:fsstress        state:D stack:    0 pid:1356196 ppid:1356177 flags:0x00004000
  [162513.517780] Call Trace:
  [162513.517786]  __schedule+0x5ce/0xd00
  [162513.517789]  ? _raw_spin_unlock_irqrestore+0x3c/0x60
  [162513.517796]  schedule+0x46/0xf0
  [162513.517810]  wait_current_trans+0xde/0x140 [btrfs]
  [162513.517814]  ? finish_wait+0x90/0x90
  [162513.517829]  start_transaction+0x37c/0x5f0 [btrfs]
  [162513.517845]  btrfs_attach_transaction_barrier+0x1f/0x50 [btrfs]
  [162513.517857]  btrfs_sync_fs+0x61/0x1c0 [btrfs]
  [162513.517862]  ? __ia32_sys_fdatasync+0x20/0x20
  [162513.517865]  iterate_supers+0x87/0xf0
  [162513.517869]  ksys_sync+0x60/0xb0
  [162513.517872]  __do_sys_sync+0xa/0x10
  [162513.517875]  do_syscall_64+0x33/0x80
  [162513.517878]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
  [162513.517881] RIP: 0033:0x7f5238f50bd7
  [162513.517883] Code: Bad RIP value.
  [162513.517885] RSP: 002b:00007fff67b978e8 EFLAGS: 00000206 ORIG_RAX: 00000000000000a2
  [162513.517887] RAX: ffffffffffffffda RBX: 000055b1fad2c560 RCX: 00007f5238f50bd7
  [162513.517889] RDX: 0000000000000000 RSI: 000000007660add2 RDI: 0000000000000053
  [162513.517891] RBP: 0000000000000032 R08: 0000000000000067 R09: 00007f5239019be0
  [162513.517893] R10: fffffffffffff24f R11: 0000000000000206 R12: 0000000000000053
  [162513.517895] R13: 00007fff67b97950 R14: 00007fff67b97906 R15: 000055b1fad1a340
  [162513.517908] INFO: task fsstress:1356197 blocked for more than 120 seconds.
  [162513.518298]       Not tainted 5.9.0-rc6-btrfs-next-69 #1
  [162513.518672] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
  [162513.519157] task:fsstress        state:D stack:    0 pid:1356197 ppid:1356177 flags:0x00000000
  [162513.519160] Call Trace:
  [162513.519165]  __schedule+0x5ce/0xd00
  [162513.519168]  ? _raw_spin_unlock_irqrestore+0x3c/0x60
  [162513.519174]  schedule+0x46/0xf0
  [162513.519190]  wait_current_trans+0xde/0x140 [btrfs]
  [162513.519193]  ? finish_wait+0x90/0x90
  [162513.519206]  start_transaction+0x4d7/0x5f0 [btrfs]
  [162513.519222]  btrfs_create+0x57/0x200 [btrfs]
  [162513.519230]  lookup_open+0x522/0x650
  [162513.519246]  path_openat+0x2b8/0xa50
  [162513.519270]  do_filp_open+0x91/0x100
  [162513.519275]  ? find_held_lock+0x32/0x90
  [162513.519280]  ? lock_acquired+0x33b/0x470
  [162513.519285]  ? do_raw_spin_unlock+0x4b/0xc0
  [162513.519287]  ? _raw_spin_unlock+0x29/0x40
  [162513.519295]  do_sys_openat2+0x20d/0x2d0
  [162513.519300]  do_sys_open+0x44/0x80
  [162513.519304]  do_syscall_64+0x33/0x80
  [162513.519307]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
  [162513.519309] RIP: 0033:0x7f5238f4a903
  [162513.519310] Code: Bad RIP value.
  [162513.519312] RSP: 002b:00007fff67b97758 EFLAGS: 00000246 ORIG_RAX: 0000000000000055
  [162513.519314] RAX: ffffffffffffffda RBX: 00000000ffffffff RCX: 00007f5238f4a903
  [162513.519316] RDX: 0000000000000000 RSI: 00000000000001b6 RDI: 000055b1fbb0d470
  [162513.519317] RBP: 00007fff67b978c0 R08: 0000000000000001 R09: 0000000000000002
  [162513.519319] R10: 00007fff67b974f7 R11: 0000000000000246 R12: 0000000000000013
  [162513.519320] R13: 00000000000001b6 R14: 00007fff67b97906 R15: 000055b1fad1c620
  [162513.519332] INFO: task btrfs:1356211 blocked for more than 120 seconds.
  [162513.519727]       Not tainted 5.9.0-rc6-btrfs-next-69 #1
  [162513.520115] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
  [162513.520508] task:btrfs           state:D stack:    0 pid:1356211 ppid:1356178 flags:0x00004002
  [162513.520511] Call Trace:
  [162513.520516]  __schedule+0x5ce/0xd00
  [162513.520519]  ? _raw_spin_unlock_irqrestore+0x3c/0x60
  [162513.520525]  schedule+0x46/0xf0
  [162513.520544]  btrfs_scrub_pause+0x11f/0x180 [btrfs]
  [162513.520548]  ? finish_wait+0x90/0x90
  [162513.520562]  btrfs_commit_transaction+0x45a/0xc30 [btrfs]
  [162513.520574]  ? start_transaction+0xe0/0x5f0 [btrfs]
  [162513.520596]  btrfs_dev_replace_finishing+0x6d8/0x711 [btrfs]
  [162513.520619]  btrfs_dev_replace_by_ioctl.cold+0x1cc/0x1fd [btrfs]
  [162513.520639]  btrfs_ioctl+0x2a25/0x36f0 [btrfs]
  [162513.520643]  ? do_sigaction+0xf3/0x240
  [162513.520645]  ? find_held_lock+0x32/0x90
  [162513.520648]  ? do_sigaction+0xf3/0x240
  [162513.520651]  ? lock_acquired+0x33b/0x470
  [162513.520655]  ? _raw_spin_unlock_irq+0x24/0x50
  [162513.520657]  ? lockdep_hardirqs_on+0x7d/0x100
  [162513.520660]  ? _raw_spin_unlock_irq+0x35/0x50
  [162513.520662]  ? do_sigaction+0xf3/0x240
  [162513.520671]  ? __x64_sys_ioctl+0x83/0xb0
  [162513.520672]  __x64_sys_ioctl+0x83/0xb0
  [162513.520677]  do_syscall_64+0x33/0x80
  [162513.520679]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
  [162513.520681] RIP: 0033:0x7fc3cd307d87
  [162513.520682] Code: Bad RIP value.
  [162513.520684] RSP: 002b:00007ffe30a56bb8 EFLAGS: 00000202 ORIG_RAX: 0000000000000010
  [162513.520686] RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 00007fc3cd307d87
  [162513.520687] RDX: 00007ffe30a57a30 RSI: 00000000ca289435 RDI: 0000000000000003
  [162513.520689] RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
  [162513.520690] R10: 0000000000000008 R11: 0000000000000202 R12: 0000000000000003
  [162513.520692] R13: 0000557323a212e0 R14: 00007ffe30a5a520 R15: 0000000000000001
  [162513.520703]
		  Showing all locks held in the system:
  [162513.520712] 1 lock held by khungtaskd/54:
  [162513.520713]  #0: ffffffffb40a91a0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x15/0x197
  [162513.520728] 1 lock held by in:imklog/596:
  [162513.520729]  #0: ffff8f3f0d781400 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x4d/0x60
  [162513.520782] 1 lock held by btrfs-transacti/1356167:
  [162513.520784]  #0: ffff8f3d810cc848 (&fs_info->transaction_kthread_mutex){+.+.}-{3:3}, at: transaction_kthread+0x4a/0x170 [btrfs]
  [162513.520798] 1 lock held by btrfs/1356190:
  [162513.520800]  #0: ffff8f3d57644470 (sb_writers#15){.+.+}-{0:0}, at: mnt_want_write_file+0x22/0x60
  [162513.520805] 1 lock held by fsstress/1356184:
  [162513.520806]  #0: ffff8f3d576440e8 (&type->s_umount_key#62){++++}-{3:3}, at: iterate_supers+0x6f/0xf0
  [162513.520811] 3 locks held by fsstress/1356185:
  [162513.520812]  #0: ffff8f3d57644470 (sb_writers#15){.+.+}-{0:0}, at: mnt_want_write+0x20/0x50
  [162513.520815]  #1: ffff8f3d80a650b8 (&type->i_mutex_dir_key#10){++++}-{3:3}, at: vfs_setxattr+0x50/0x120
  [162513.520820]  #2: ffff8f3d57644690 (sb_internal#2){.+.+}-{0:0}, at: start_transaction+0x40e/0x5f0 [btrfs]
  [162513.520833] 1 lock held by fsstress/1356196:
  [162513.520834]  #0: ffff8f3d576440e8 (&type->s_umount_key#62){++++}-{3:3}, at: iterate_supers+0x6f/0xf0
  [162513.520838] 3 locks held by fsstress/1356197:
  [162513.520839]  #0: ffff8f3d57644470 (sb_writers#15){.+.+}-{0:0}, at: mnt_want_write+0x20/0x50
  [162513.520843]  #1: ffff8f3d506465e8 (&type->i_mutex_dir_key#10){++++}-{3:3}, at: path_openat+0x2a7/0xa50
  [162513.520846]  #2: ffff8f3d57644690 (sb_internal#2){.+.+}-{0:0}, at: start_transaction+0x40e/0x5f0 [btrfs]
  [162513.520858] 2 locks held by btrfs/1356211:
  [162513.520859]  #0: ffff8f3d810cde30 (&fs_info->dev_replace.lock_finishing_cancel_unmount){+.+.}-{3:3}, at: btrfs_dev_replace_finishing+0x52/0x711 [btrfs]
  [162513.520877]  #1: ffff8f3d57644690 (sb_internal#2){.+.+}-{0:0}, at: start_transaction+0x40e/0x5f0 [btrfs]

This was weird because the stack traces show that a transaction commit,
triggered by a device replace operation, is blocking trying to pause any
running scrubs but there are no stack traces of blocked tasks doing a
scrub.

After poking around with drgn, I noticed there was a scrub task that was
constantly running and blocking for shorts periods of time:

  >>> t = find_task(prog, 1356190)
  >>> prog.stack_trace(t)
  #0  __schedule+0x5ce/0xcfc
  #1  schedule+0x46/0xe4
  #2  schedule_timeout+0x1df/0x475
  #3  btrfs_reada_wait+0xda/0x132
  #4  scrub_stripe+0x2a8/0x112f
  #5  scrub_chunk+0xcd/0x134
  #6  scrub_enumerate_chunks+0x29e/0x5ee
  #7  btrfs_scrub_dev+0x2d5/0x91b
  #8  btrfs_ioctl+0x7f5/0x36e7
  rockchip-linux#9  __x64_sys_ioctl+0x83/0xb0
  rockchip-linux#10 do_syscall_64+0x33/0x77
  rockchip-linux#11 entry_SYSCALL_64+0x7c/0x156

Which corresponds to:

int btrfs_reada_wait(void *handle)
{
    struct reada_control *rc = handle;
    struct btrfs_fs_info *fs_info = rc->fs_info;

    while (atomic_read(&rc->elems)) {
        if (!atomic_read(&fs_info->reada_works_cnt))
            reada_start_machine(fs_info);
        wait_event_timeout(rc->wait, atomic_read(&rc->elems) == 0,
                          (HZ + 9) / 10);
    }
(...)

So the counter "rc->elems" was set to 1 and never decreased to 0, causing
the scrub task to loop forever in that function. Then I used the following
script for drgn to check the readahead requests:

  $ cat dump_reada.py
  import sys
  import drgn
  from drgn import NULL, Object, cast, container_of, execscript, \
      reinterpret, sizeof
  from drgn.helpers.linux import *

  mnt_path = b"/home/fdmanana/btrfs-tests/scratch_1"

  mnt = None
  for mnt in for_each_mount(prog, dst = mnt_path):
      pass

  if mnt is None:
      sys.stderr.write(f'Error: mount point {mnt_path} not found\n')
      sys.exit(1)

  fs_info = cast('struct btrfs_fs_info *', mnt.mnt.mnt_sb.s_fs_info)

  def dump_re(re):
      nzones = re.nzones.value_()
      print(f're at {hex(re.value_())}')
      print(f'\t logical {re.logical.value_()}')
      print(f'\t refcnt {re.refcnt.value_()}')
      print(f'\t nzones {nzones}')
      for i in range(nzones):
          dev = re.zones[i].device
          name = dev.name.str.string_()
          print(f'\t\t dev id {dev.devid.value_()} name {name}')
      print()

  for _, e in radix_tree_for_each(fs_info.reada_tree):
      re = cast('struct reada_extent *', e)
      dump_re(re)

  $ drgn dump_reada.py
  re at 0xffff8f3da9d25ad8
          logical 38928384
          refcnt 1
          nzones 1
                 dev id 0 name b'/dev/sdd'
  $

So there was one readahead extent with a single zone corresponding to the
source device of that last device replace operation logged in dmesg/syslog.
Also the ID of that zone's device was 0 which is a special value set in
the source device of a device replace operation when the operation finishes
(constant BTRFS_DEV_REPLACE_DEVID set at btrfs_dev_replace_finishing()),
confirming again that device /dev/sdd was the source of a device replace
operation.

Normally there should be as many zones in the readahead extent as there are
devices, and I wasn't expecting the extent to be in a block group with a
'single' profile, so I went and confirmed with the following drgn script
that there weren't any single profile block groups:

  $ cat dump_block_groups.py
  import sys
  import drgn
  from drgn import NULL, Object, cast, container_of, execscript, \
      reinterpret, sizeof
  from drgn.helpers.linux import *

  mnt_path = b"/home/fdmanana/btrfs-tests/scratch_1"

  mnt = None
  for mnt in for_each_mount(prog, dst = mnt_path):
      pass

  if mnt is None:
      sys.stderr.write(f'Error: mount point {mnt_path} not found\n')
      sys.exit(1)

  fs_info = cast('struct btrfs_fs_info *', mnt.mnt.mnt_sb.s_fs_info)

  BTRFS_BLOCK_GROUP_DATA = (1 << 0)
  BTRFS_BLOCK_GROUP_SYSTEM = (1 << 1)
  BTRFS_BLOCK_GROUP_METADATA = (1 << 2)
  BTRFS_BLOCK_GROUP_RAID0 = (1 << 3)
  BTRFS_BLOCK_GROUP_RAID1 = (1 << 4)
  BTRFS_BLOCK_GROUP_DUP = (1 << 5)
  BTRFS_BLOCK_GROUP_RAID10 = (1 << 6)
  BTRFS_BLOCK_GROUP_RAID5 = (1 << 7)
  BTRFS_BLOCK_GROUP_RAID6 = (1 << 8)
  BTRFS_BLOCK_GROUP_RAID1C3 = (1 << 9)
  BTRFS_BLOCK_GROUP_RAID1C4 = (1 << 10)

  def bg_flags_string(bg):
      flags = bg.flags.value_()
      ret = ''
      if flags & BTRFS_BLOCK_GROUP_DATA:
          ret = 'data'
      if flags & BTRFS_BLOCK_GROUP_METADATA:
          if len(ret) > 0:
              ret += '|'
          ret += 'meta'
      if flags & BTRFS_BLOCK_GROUP_SYSTEM:
          if len(ret) > 0:
              ret += '|'
          ret += 'system'
      if flags & BTRFS_BLOCK_GROUP_RAID0:
          ret += ' raid0'
      elif flags & BTRFS_BLOCK_GROUP_RAID1:
          ret += ' raid1'
      elif flags & BTRFS_BLOCK_GROUP_DUP:
          ret += ' dup'
      elif flags & BTRFS_BLOCK_GROUP_RAID10:
          ret += ' raid10'
      elif flags & BTRFS_BLOCK_GROUP_RAID5:
          ret += ' raid5'
      elif flags & BTRFS_BLOCK_GROUP_RAID6:
          ret += ' raid6'
      elif flags & BTRFS_BLOCK_GROUP_RAID1C3:
          ret += ' raid1c3'
      elif flags & BTRFS_BLOCK_GROUP_RAID1C4:
          ret += ' raid1c4'
      else:
          ret += ' single'

      return ret

  def dump_bg(bg):
      print()
      print(f'block group at {hex(bg.value_())}')
      print(f'\t start {bg.start.value_()} length {bg.length.value_()}')
      print(f'\t flags {bg.flags.value_()} - {bg_flags_string(bg)}')

  bg_root = fs_info.block_group_cache_tree.address_of_()
  for bg in rbtree_inorder_for_each_entry('struct btrfs_block_group', bg_root, 'cache_node'):
      dump_bg(bg)

  $ drgn dump_block_groups.py

  block group at 0xffff8f3d673b0400
         start 22020096 length 16777216
         flags 258 - system raid6

  block group at 0xffff8f3d53ddb400
         start 38797312 length 536870912
         flags 260 - meta raid6

  block group at 0xffff8f3d5f4d9c00
         start 575668224 length 2147483648
         flags 257 - data raid6

  block group at 0xffff8f3d08189000
         start 2723151872 length 67108864
         flags 258 - system raid6

  block group at 0xffff8f3db70ff000
         start 2790260736 length 1073741824
         flags 260 - meta raid6

  block group at 0xffff8f3d5f4dd800
         start 3864002560 length 67108864
         flags 258 - system raid6

  block group at 0xffff8f3d67037000
         start 3931111424 length 2147483648
         flags 257 - data raid6
  $

So there were only 2 reasons left for having a readahead extent with a
single zone: reada_find_zone(), called when creating a readahead extent,
returned NULL either because we failed to find the corresponding block
group or because a memory allocation failed. With some additional and
custom tracing I figured out that on every further ocurrence of the
problem the block group had just been deleted when we were looping to
create the zones for the readahead extent (at reada_find_extent()), so we
ended up with only one zone in the readahead extent, corresponding to a
device that ends up getting replaced.

So after figuring that out it became obvious why the hang happens:

1) Task A starts a scrub on any device of the filesystem, except for
   device /dev/sdd;

2) Task B starts a device replace with /dev/sdd as the source device;

3) Task A calls btrfs_reada_add() from scrub_stripe() and it is currently
   starting to scrub a stripe from block group X. This call to
   btrfs_reada_add() is the one for the extent tree. When btrfs_reada_add()
   calls reada_add_block(), it passes the logical address of the extent
   tree's root node as its 'logical' argument - a value of 38928384;

4) Task A then enters reada_find_extent(), called from reada_add_block().
   It finds there isn't any existing readahead extent for the logical
   address 38928384, so it proceeds to the path of creating a new one.

   It calls btrfs_map_block() to find out which stripes exist for the block
   group X. On the first iteration of the for loop that iterates over the
   stripes, it finds the stripe for device /dev/sdd, so it creates one
   zone for that device and adds it to the readahead extent. Before getting
   into the second iteration of the loop, the cleanup kthread deletes block
   group X because it was empty. So in the iterations for the remaining
   stripes it does not add more zones to the readahead extent, because the
   calls to reada_find_zone() returned NULL because they couldn't find
   block group X anymore.

   As a result the new readahead extent has a single zone, corresponding to
   the device /dev/sdd;

4) Before task A returns to btrfs_reada_add() and queues the readahead job
   for the readahead work queue, task B finishes the device replace and at
   btrfs_dev_replace_finishing() swaps the device /dev/sdd with the new
   device /dev/sdg;

5) Task A returns to reada_add_block(), which increments the counter
   "->elems" of the reada_control structure allocated at btrfs_reada_add().

   Then it returns back to btrfs_reada_add() and calls
   reada_start_machine(). This queues a job in the readahead work queue to
   run the function reada_start_machine_worker(), which calls
   __reada_start_machine().

   At __reada_start_machine() we take the device list mutex and for each
   device found in the current device list, we call
   reada_start_machine_dev() to start the readahead work. However at this
   point the device /dev/sdd was already freed and is not in the device
   list anymore.

   This means the corresponding readahead for the extent at 38928384 is
   never started, and therefore the "->elems" counter of the reada_control
   structure allocated at btrfs_reada_add() never goes down to 0, causing
   the call to btrfs_reada_wait(), done by the scrub task, to wait forever.

Note that the readahead request can be made either after the device replace
started or before it started, however in pratice it is very unlikely that a
device replace is able to start after a readahead request is made and is
able to complete before the readahead request completes - maybe only on a
very small and nearly empty filesystem.

This hang however is not the only problem we can have with readahead and
device removals. When the readahead extent has other zones other than the
one corresponding to the device that is being removed (either by a device
replace or a device remove operation), we risk having a use-after-free on
the device when dropping the last reference of the readahead extent.

For example if we create a readahead extent with two zones, one for the
device /dev/sdd and one for the device /dev/sde:

1) Before the readahead worker starts, the device /dev/sdd is removed,
   and the corresponding btrfs_device structure is freed. However the
   readahead extent still has the zone pointing to the device structure;

2) When the readahead worker starts, it only finds device /dev/sde in the
   current device list of the filesystem;

3) It starts the readahead work, at reada_start_machine_dev(), using the
   device /dev/sde;

4) Then when it finishes reading the extent from device /dev/sde, it calls
   __readahead_hook() which ends up dropping the last reference on the
   readahead extent through the last call to reada_extent_put();

5) At reada_extent_put() it iterates over each zone of the readahead extent
   and attempts to delete an element from the device's 'reada_extents'
   radix tree, resulting in a use-after-free, as the device pointer of the
   zone for /dev/sdd is now stale. We can also access the device after
   dropping the last reference of a zone, through reada_zone_release(),
   also called by reada_extent_put().

And a device remove suffers the same problem, however since it shrinks the
device size down to zero before removing the device, it is very unlikely to
still have readahead requests not completed by the time we free the device,
the only possibility is if the device has a very little space allocated.

While the hang problem is exclusive to scrub, since it is currently the
only user of btrfs_reada_add() and btrfs_reada_wait(), the use-after-free
problem affects any path that triggers readhead, which includes
btree_readahead_hook() and __readahead_hook() (a readahead worker can
trigger readahed for the children of a node) for example - any path that
ends up calling reada_add_block() can trigger the use-after-free after a
device is removed.

So fix this by waiting for any readahead requests for a device to complete
before removing a device, ensuring that while waiting for existing ones no
new ones can be made.

This problem has been around for a very long time - the readahead code was
added in 2011, device remove exists since 2008 and device replace was
introduced in 2013, hard to pick a specific commit for a git Fixes tag.

CC: stable@vger.kernel.org # 4.4+
Reviewed-by: Josef Bacik <josef@toxicpanda.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: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
friendlyarm pushed a commit to friendlyarm/kernel-rockchip that referenced this issue Apr 2, 2021
…g system shutdown

[ Upstream commit 45a2702 ]

During Coldboot stress tests, system encountered the following panic.
Panic logs depicts rt5682_i2c_shutdown() happened first and then later
jack detect handler workqueue function triggered.
This situation causes panic as rt5682_i2c_shutdown() resets codec.
Fix this panic by cancelling all jack detection delayed work.

Panic log:
[   20.936124] sof_pci_shutdown
[   20.940248] snd_sof_device_shutdown
[   20.945023] snd_sof_shutdown
[   21.126849] rt5682_i2c_shutdown
[   21.286053] rt5682_jack_detect_handler
[   21.291235] BUG: kernel NULL pointer dereference, address: 000000000000037c
[   21.299302] #PF: supervisor read access in kernel mode
[   21.305254] #PF: error_code(0x0000) - not-present page
[   21.311218] PGD 0 P4D 0
[   21.314155] Oops: 0000 [#1] PREEMPT SMP NOPTI
[   21.319206] CPU: 2 PID: 123 Comm: kworker/2:3 Tainted: G     U            5.4.68 rockchip-linux#10
[   21.333687] ACPI: Preparing to enter system sleep state S5
[   21.337669] Workqueue: events_power_efficient rt5682_jack_detect_handler [snd_soc_rt5682]
[   21.337671] RIP: 0010:rt5682_jack_detect_handler+0x6c/0x279 [snd_soc_rt5682]

Fixes: a50067d ('ASoC: rt5682: split i2c driver into separate module')
Signed-off-by: Jairaj Arava <jairaj.arava@intel.com>
Signed-off-by: Sathyanarayana Nujella <sathyanarayana.nujella@intel.com>
Reviewed-by: Pierre-Louis Bossart <pierre-louis.bossart@intel.com>
Reviewed-by: Shuming Fan <shumingf@realtek.com>
Signed-off-by: Ranjani Sridharan <ranjani.sridharan@linux.intel.com>
Link: https://lore.kernel.org/r/20210205171428.2344210-1-ranjani.sridharan@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
friendlyarm pushed a commit to friendlyarm/kernel-rockchip that referenced this issue Apr 2, 2021
[ Upstream commit c5c97ca ]

The ubsan reported the following error.  It was because sample's raw
data missed u32 padding at the end.  So it broke the alignment of the
array after it.

The raw data contains an u32 size prefix so the data size should have
an u32 padding after 8-byte aligned data.

27: Sample parsing  :util/synthetic-events.c:1539:4:
  runtime error: store to misaligned address 0x62100006b9bc for type
  '__u64' (aka 'unsigned long long'), which requires 8 byte alignment
0x62100006b9bc: note: pointer points here
  00 00 00 00 ff ff ff ff  ff ff ff ff ff ff ff ff  ff ff ff ff ff ff ff ff  ff ff ff ff ff ff ff ff
              ^
    #0 0x561532a9fc96 in perf_event__synthesize_sample util/synthetic-events.c:1539:13
    #1 0x5615327f4a4f in do_test tests/sample-parsing.c:284:8
    #2 0x5615327f3f50 in test__sample_parsing tests/sample-parsing.c:381:9
    #3 0x56153279d3a1 in run_test tests/builtin-test.c:424:9
    #4 0x56153279c836 in test_and_print tests/builtin-test.c:454:9
    #5 0x56153279b7eb in __cmd_test tests/builtin-test.c:675:4
    #6 0x56153279abf0 in cmd_test tests/builtin-test.c:821:9
    #7 0x56153264e796 in run_builtin perf.c:312:11
    #8 0x56153264cf03 in handle_internal_command perf.c:364:8
    rockchip-linux#9 0x56153264e47d in run_argv perf.c:408:2
    rockchip-linux#10 0x56153264c9a9 in main perf.c:538:3
    rockchip-linux#11 0x7f137ab6fbbc in __libc_start_main (/lib64/libc.so.6+0x38bbc)
    rockchip-linux#12 0x561532596828 in _start ...

SUMMARY: UndefinedBehaviorSanitizer: misaligned-pointer-use
 util/synthetic-events.c:1539:4 in

Fixes: 045f8cd ("perf tests: Add a sample parsing test")
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: https://lore.kernel.org/r/20210214091638.519643-1-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
friendlyarm pushed a commit to friendlyarm/kernel-rockchip that referenced this issue Apr 2, 2021
commit 4d14c5c upstream

Calling btrfs_qgroup_reserve_meta_prealloc from
btrfs_delayed_inode_reserve_metadata can result in flushing delalloc
while holding a transaction and delayed node locks. This is deadlock
prone. In the past multiple commits:

 * ae5e070 ("btrfs: qgroup: don't try to wait flushing if we're
already holding a transaction")

 * 6f23277 ("btrfs: qgroup: don't commit transaction when we already
 hold the handle")

Tried to solve various aspects of this but this was always a
whack-a-mole game. Unfortunately those 2 fixes don't solve a deadlock
scenario involving btrfs_delayed_node::mutex. Namely, one thread
can call btrfs_dirty_inode as a result of reading a file and modifying
its atime:

  PID: 6963   TASK: ffff8c7f3f94c000  CPU: 2   COMMAND: "test"
  #0  __schedule at ffffffffa529e07d
  #1  schedule at ffffffffa529e4ff
  #2  schedule_timeout at ffffffffa52a1bdd
  #3  wait_for_completion at ffffffffa529eeea             <-- sleeps with delayed node mutex held
  #4  start_delalloc_inodes at ffffffffc0380db5
  #5  btrfs_start_delalloc_snapshot at ffffffffc0393836
  #6  try_flush_qgroup at ffffffffc03f04b2
  #7  __btrfs_qgroup_reserve_meta at ffffffffc03f5bb6     <-- tries to reserve space and starts delalloc inodes.
  #8  btrfs_delayed_update_inode at ffffffffc03e31aa      <-- acquires delayed node mutex
  rockchip-linux#9  btrfs_update_inode at ffffffffc0385ba8
 rockchip-linux#10  btrfs_dirty_inode at ffffffffc038627b               <-- TRANSACTIION OPENED
 rockchip-linux#11  touch_atime at ffffffffa4cf0000
 rockchip-linux#12  generic_file_read_iter at ffffffffa4c1f123
 rockchip-linux#13  new_sync_read at ffffffffa4ccdc8a
 rockchip-linux#14  vfs_read at ffffffffa4cd0849
 rockchip-linux#15  ksys_read at ffffffffa4cd0bd1
 rockchip-linux#16  do_syscall_64 at ffffffffa4a052eb
 rockchip-linux#17  entry_SYSCALL_64_after_hwframe at ffffffffa540008c

This will cause an asynchronous work to flush the delalloc inodes to
happen which can try to acquire the same delayed_node mutex:

  PID: 455    TASK: ffff8c8085fa4000  CPU: 5   COMMAND: "kworker/u16:30"
  #0  __schedule at ffffffffa529e07d
  #1  schedule at ffffffffa529e4ff
  #2  schedule_preempt_disabled at ffffffffa529e80a
  #3  __mutex_lock at ffffffffa529fdcb                    <-- goes to sleep, never wakes up.
  #4  btrfs_delayed_update_inode at ffffffffc03e3143      <-- tries to acquire the mutex
  #5  btrfs_update_inode at ffffffffc0385ba8              <-- this is the same inode that pid 6963 is holding
  #6  cow_file_range_inline.constprop.78 at ffffffffc0386be7
  #7  cow_file_range at ffffffffc03879c1
  #8  btrfs_run_delalloc_range at ffffffffc038894c
  rockchip-linux#9  writepage_delalloc at ffffffffc03a3c8f
 rockchip-linux#10  __extent_writepage at ffffffffc03a4c01
 rockchip-linux#11  extent_write_cache_pages at ffffffffc03a500b
 rockchip-linux#12  extent_writepages at ffffffffc03a6de2
 rockchip-linux#13  do_writepages at ffffffffa4c277eb
 rockchip-linux#14  __filemap_fdatawrite_range at ffffffffa4c1e5bb
 rockchip-linux#15  btrfs_run_delalloc_work at ffffffffc0380987         <-- starts running delayed nodes
 rockchip-linux#16  normal_work_helper at ffffffffc03b706c
 rockchip-linux#17  process_one_work at ffffffffa4aba4e4
 rockchip-linux#18  worker_thread at ffffffffa4aba6fd
 rockchip-linux#19  kthread at ffffffffa4ac0a3d
 rockchip-linux#20  ret_from_fork at ffffffffa54001ff

To fully address those cases the complete fix is to never issue any
flushing while holding the transaction or the delayed node lock. This
patch achieves it by calling qgroup_reserve_meta directly which will
either succeed without flushing or will fail and return -EDQUOT. In the
latter case that return value is going to be propagated to
btrfs_dirty_inode which will fallback to start a new transaction. That's
fine as the majority of time we expect the inode will have
BTRFS_DELAYED_NODE_INODE_DIRTY flag set which will result in directly
copying the in-memory state.

Fixes: c53e965 ("btrfs: qgroup: try to flush qgroup space when we get -EDQUOT")
CC: stable@vger.kernel.org # 5.10+
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
[sudip: adjust context]
Signed-off-by: Sudip Mukherjee <sudipm.mukherjee@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
friendlyarm pushed a commit to friendlyarm/kernel-rockchip that referenced this issue Apr 2, 2021
commit f06391c upstream.

[ 6684.493350] Unable to handle kernel paging request at virtual address ffff800011c5b0f0
[ 6684.498531] mmc0: card 0001 removed
[ 6684.501556] Mem abort info:
[ 6684.509681]   ESR = 0x96000047
[ 6684.512786]   EC = 0x25: DABT (current EL), IL = 32 bits
[ 6684.518394]   SET = 0, FnV = 0
[ 6684.521707]   EA = 0, S1PTW = 0
[ 6684.524998] Data abort info:
[ 6684.528236]   ISV = 0, ISS = 0x00000047
[ 6684.532986]   CM = 0, WnR = 1
[ 6684.536129] swapper pgtable: 4k pages, 48-bit VAs, pgdp=0000000081b22000
[ 6684.543923] [ffff800011c5b0f0] pgd=00000000bffff003, p4d=00000000bffff003, pud=00000000bfffe003, pmd=00000000900e1003, pte=0000000000000000
[ 6684.557915] Internal error: Oops: 96000047 [#1] PREEMPT SMP
[ 6684.564240] Modules linked in: sdhci_esdhc_imx(-) sdhci_pltfm sdhci cqhci mmc_block mmc_core fsl_jr_uio caam_jr caamkeyblob_desc caamhash_desc caamalg_desc crypto_engine rng_core authenc libdes crct10dif_ce flexcan can_dev caam error [last unloaded: mmc_core]
[ 6684.587281] CPU: 0 PID: 79138 Comm: kworker/0:3H Not tainted 5.10.9-01410-g3ba33182767b-dirty rockchip-linux#10
[ 6684.596160] Hardware name: Freescale i.MX8DXL EVK (DT)
[ 6684.601320] Workqueue: kblockd blk_mq_run_work_fn

[ 6684.606094] pstate: 40000005 (nZcv daif -PAN -UAO -TCO BTYPE=--)
[ 6684.612286] pc : cqhci_request+0x148/0x4e8 [cqhci]
^GMessage from syslogd@  at Thu Jan  1 01:51:24 1970 ...[ 6684.617085] lr : cqhci_request+0x314/0x4e8 [cqhci]
[ 6684.626734] sp : ffff80001243b9f0
[ 6684.630049] x29: ffff80001243b9f0 x28: ffff00002c3dd000
[ 6684.635367] x27: 0000000000000001 x26: 0000000000000001
[ 6684.640690] x25: ffff00002c451000 x24: 000000000000000f
[ 6684.646007] x23: ffff000017e71c80 x22: ffff00002c451000
[ 6684.651326] x21: ffff00002c0f3550 x20: ffff00002c0f3550
[ 6684.656651] x19: ffff000017d46880 x18: ffff00002cea1500
[ 6684.661977] x17: 0000000000000000 x16: 0000000000000000
[ 6684.667294] x15: 000001ee628e3ed1 x14: 0000000000000278
[ 6684.672610] x13: 0000000000000001 x12: 0000000000000001
[ 6684.677927] x11: 0000000000000000 x10: 0000000000000000
[ 6684.683243] x9 : 000000000000002b x8 : 0000000000001000
[ 6684.688560] x7 : 0000000000000010 x6 : ffff00002c0f3678
[ 6684.693886] x5 : 000000000000000f x4 : ffff800011c5b000
[ 6684.699211] x3 : 000000000002d988 x2 : 0000000000000008
[ 6684.704537] x1 : 00000000000000f0 x0 : 0002d9880008102f
[ 6684.709854] Call trace:
[ 6684.712313]  cqhci_request+0x148/0x4e8 [cqhci]
[ 6684.716803]  mmc_cqe_start_req+0x58/0x68 [mmc_core]
[ 6684.721698]  mmc_blk_mq_issue_rq+0x460/0x810 [mmc_block]
[ 6684.727018]  mmc_mq_queue_rq+0x118/0x2b0 [mmc_block]

The problem occurs when cqhci_request() get called after cqhci_disable() as
it leads to access of allocated memory that has already been freed. Let's
fix the problem by calling cqhci_disable() a bit later in the remove path.

Signed-off-by: Frank Li <Frank.Li@nxp.com>
Diagnosed-by: Adrian Hunter <adrian.hunter@intel.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Link: https://lore.kernel.org/r/20210303174248.542175-1-Frank.Li@nxp.com
Fixes: f690f44 ("mmc: mmc: Enable CQE's")
Cc: stable@vger.kernel.org
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
friendlyarm pushed a commit to friendlyarm/kernel-rockchip that referenced this issue Aug 31, 2021
…tances

commit cad83c9 upstream.

As syzbot reported, there is an use-after-free issue during f2fs recovery:

Use-after-free write at 0xffff88823bc16040 (in kfence-rockchip-linux#10):
 kmem_cache_destroy+0x1f/0x120 mm/slab_common.c:486
 f2fs_recover_fsync_data+0x75b0/0x8380 fs/f2fs/recovery.c:869
 f2fs_fill_super+0x9393/0xa420 fs/f2fs/super.c:3945
 mount_bdev+0x26c/0x3a0 fs/super.c:1367
 legacy_get_tree+0xea/0x180 fs/fs_context.c:592
 vfs_get_tree+0x86/0x270 fs/super.c:1497
 do_new_mount fs/namespace.c:2905 [inline]
 path_mount+0x196f/0x2be0 fs/namespace.c:3235
 do_mount fs/namespace.c:3248 [inline]
 __do_sys_mount fs/namespace.c:3456 [inline]
 __se_sys_mount+0x2f9/0x3b0 fs/namespace.c:3433
 do_syscall_64+0x3f/0xb0 arch/x86/entry/common.c:47
 entry_SYSCALL_64_after_hwframe+0x44/0xae

The root cause is multi f2fs filesystem instances can race on accessing
global fsync_entry_slab pointer, result in use-after-free issue of slab
cache, fixes to init/destroy this slab cache only once during module
init/destroy procedure to avoid this issue.

Reported-by: syzbot+9d90dad32dd9727ed084@syzkaller.appspotmail.com
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
mcerveny pushed a commit to mcerveny/rockchip-linux that referenced this issue Sep 18, 2021
rtk_btusb: RTKBT_RELEASE_NAME: 20200318_BT_ANDROID_9.0
rtk_btusb: Realtek Bluetooth USB driver module init, version 5.2.1
rtk_btusb: Register usb char device interface for BT driver
BUG: spinlock bad magic on CPU#0, swapper/0/1
 lock: running_flag_lock+0x0/0x38, .magic: 00000000, .owner: <none>/-1, .owner_cpu: 0
CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.4.194 rockchip-linux#10
Hardware name: Rockchip RK3399 Evaluation Board v3 (Android) (DT)
Call trace:
[<ffffff800808a8c0>] dump_backtrace+0x0/0x1f4
[<ffffff800808aac8>] show_stack+0x14/0x1c
[<ffffff8008416248>] dump_stack+0xb4/0xf4
[<ffffff800810b1c0>] spin_dump+0x70/0x8c
[<ffffff800810b204>] spin_bug+0x28/0x34
[<ffffff800810b2a0>] do_raw_spin_lock+0x34/0x158
[<ffffff8008d68650>] _raw_spin_lock+0x48/0x54
[<ffffff80093b996c>] btusb_init+0x200/0x21c
[<ffffff80080834a8>] do_one_initcall+0x84/0x1a8
[<ffffff8009380f10>] kernel_init_freeable+0x278/0x27c
[<ffffff8008d61d3c>] kernel_init+0x10/0xf8
[<ffffff80080832d0>] ret_from_fork+0x10/0x40

Fixes: 4c267a4 ("Bluetooth: rtk_btusb: update rtk_btusb to version 5.2.1")
Change-Id: I6ea6c46a5abccc5848ec6e1538c4d7109135b725
Signed-off-by: Tao Huang <huangtao@rock-chips.com>
friendlyarm pushed a commit to friendlyarm/kernel-rockchip that referenced this issue Jul 22, 2022
[ Upstream commit 6b9dbed ]

pty_write() invokes kmalloc() which may invoke a normal printk() to print
failure message.  This can cause a deadlock in the scenario reported by
syz-bot below:

       CPU0              CPU1                    CPU2
       ----              ----                    ----
                         lock(console_owner);
                                                 lock(&port_lock_key);
  lock(&port->lock);
                         lock(&port_lock_key);
                                                 lock(&port->lock);
  lock(console_owner);

As commit dbdda84 ("printk: Add console owner and waiter logic to
load balance console writes") said, such deadlock can be prevented by
using printk_deferred() in kmalloc() (which is invoked in the section
guarded by the port->lock).  But there are too many printk() on the
kmalloc() path, and kmalloc() can be called from anywhere, so changing
printk() to printk_deferred() is too complicated and inelegant.

Therefore, this patch chooses to specify __GFP_NOWARN to kmalloc(), so
that printk() will not be called, and this deadlock problem can be
avoided.

Syzbot reported the following lockdep error:

======================================================
WARNING: possible circular locking dependency detected
5.4.143-00237-g08ccc19a-dirty rockchip-linux#10 Not tainted
------------------------------------------------------
syz-executor.4/29420 is trying to acquire lock:
ffffffff8aedb2a0 (console_owner){....}-{0:0}, at: console_trylock_spinning kernel/printk/printk.c:1752 [inline]
ffffffff8aedb2a0 (console_owner){....}-{0:0}, at: vprintk_emit+0x2ca/0x470 kernel/printk/printk.c:2023

but task is already holding lock:
ffff8880119c9158 (&port->lock){-.-.}-{2:2}, at: pty_write+0xf4/0x1f0 drivers/tty/pty.c:120

which lock already depends on the new lock.

the existing dependency chain (in reverse order) is:

-> #2 (&port->lock){-.-.}-{2:2}:
       __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
       _raw_spin_lock_irqsave+0x35/0x50 kernel/locking/spinlock.c:159
       tty_port_tty_get drivers/tty/tty_port.c:288 [inline]          		<-- lock(&port->lock);
       tty_port_default_wakeup+0x1d/0xb0 drivers/tty/tty_port.c:47
       serial8250_tx_chars+0x530/0xa80 drivers/tty/serial/8250/8250_port.c:1767
       serial8250_handle_irq.part.0+0x31f/0x3d0 drivers/tty/serial/8250/8250_port.c:1854
       serial8250_handle_irq drivers/tty/serial/8250/8250_port.c:1827 [inline] 	<-- lock(&port_lock_key);
       serial8250_default_handle_irq+0xb2/0x220 drivers/tty/serial/8250/8250_port.c:1870
       serial8250_interrupt+0xfd/0x200 drivers/tty/serial/8250/8250_core.c:126
       __handle_irq_event_percpu+0x109/0xa50 kernel/irq/handle.c:156
       [...]

-> #1 (&port_lock_key){-.-.}-{2:2}:
       __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
       _raw_spin_lock_irqsave+0x35/0x50 kernel/locking/spinlock.c:159
       serial8250_console_write+0x184/0xa40 drivers/tty/serial/8250/8250_port.c:3198
										<-- lock(&port_lock_key);
       call_console_drivers kernel/printk/printk.c:1819 [inline]
       console_unlock+0x8cb/0xd00 kernel/printk/printk.c:2504
       vprintk_emit+0x1b5/0x470 kernel/printk/printk.c:2024			<-- lock(console_owner);
       vprintk_func+0x8d/0x250 kernel/printk/printk_safe.c:394
       printk+0xba/0xed kernel/printk/printk.c:2084
       register_console+0x8b3/0xc10 kernel/printk/printk.c:2829
       univ8250_console_init+0x3a/0x46 drivers/tty/serial/8250/8250_core.c:681
       console_init+0x49d/0x6d3 kernel/printk/printk.c:2915
       start_kernel+0x5e9/0x879 init/main.c:713
       secondary_startup_64+0xa4/0xb0 arch/x86/kernel/head_64.S:241

-> #0 (console_owner){....}-{0:0}:
       [...]
       lock_acquire+0x127/0x340 kernel/locking/lockdep.c:4734
       console_trylock_spinning kernel/printk/printk.c:1773 [inline]		<-- lock(console_owner);
       vprintk_emit+0x307/0x470 kernel/printk/printk.c:2023
       vprintk_func+0x8d/0x250 kernel/printk/printk_safe.c:394
       printk+0xba/0xed kernel/printk/printk.c:2084
       fail_dump lib/fault-inject.c:45 [inline]
       should_fail+0x67b/0x7c0 lib/fault-inject.c:144
       __should_failslab+0x152/0x1c0 mm/failslab.c:33
       should_failslab+0x5/0x10 mm/slab_common.c:1224
       slab_pre_alloc_hook mm/slab.h:468 [inline]
       slab_alloc_node mm/slub.c:2723 [inline]
       slab_alloc mm/slub.c:2807 [inline]
       __kmalloc+0x72/0x300 mm/slub.c:3871
       kmalloc include/linux/slab.h:582 [inline]
       tty_buffer_alloc+0x23f/0x2a0 drivers/tty/tty_buffer.c:175
       __tty_buffer_request_room+0x156/0x2a0 drivers/tty/tty_buffer.c:273
       tty_insert_flip_string_fixed_flag+0x93/0x250 drivers/tty/tty_buffer.c:318
       tty_insert_flip_string include/linux/tty_flip.h:37 [inline]
       pty_write+0x126/0x1f0 drivers/tty/pty.c:122				<-- lock(&port->lock);
       n_tty_write+0xa7a/0xfc0 drivers/tty/n_tty.c:2356
       do_tty_write drivers/tty/tty_io.c:961 [inline]
       tty_write+0x512/0x930 drivers/tty/tty_io.c:1045
       __vfs_write+0x76/0x100 fs/read_write.c:494
       [...]

other info that might help us debug this:

Chain exists of:
  console_owner --> &port_lock_key --> &port->lock

Link: https://lkml.kernel.org/r/20220511061951.1114-2-zhengqi.arch@bytedance.com
Link: https://lkml.kernel.org/r/20220510113809.80626-2-zhengqi.arch@bytedance.com
Fixes: b6da31b ("tty: Fix data race in tty_insert_flip_string_fixed_flag")
Signed-off-by: Qi Zheng <zhengqi.arch@bytedance.com>
Acked-by: Jiri Slaby <jirislaby@kernel.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Caesar-github pushed a commit that referenced this issue Sep 3, 2022
Luca Abeni reported this:
| BUG: scheduling while atomic: kworker/u8:2/15203/0x00000003
| CPU: 1 PID: 15203 Comm: kworker/u8:2 Not tainted 4.19.1-rt3 #10
| Call Trace:
|  rt_spin_lock+0x3f/0x50
|  gen6_read32+0x45/0x1d0 [i915]
|  g4x_get_vblank_counter+0x36/0x40 [i915]
|  trace_event_raw_event_i915_pipe_update_start+0x7d/0xf0 [i915]

The tracing events use trace_i915_pipe_update_start() among other events
use functions acquire spin locks. A few trace points use
intel_get_crtc_scanline(), others use ->get_vblank_counter() wich also
might acquire a sleeping lock.

Based on this I don't see any other way than disable trace points on RT.

Cc: stable-rt@vger.kernel.org
Reported-by: Luca Abeni <lucabe72@gmail.com>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Caesar-github pushed a commit that referenced this issue Nov 3, 2022
Luca Abeni reported this:
| BUG: scheduling while atomic: kworker/u8:2/15203/0x00000003
| CPU: 1 PID: 15203 Comm: kworker/u8:2 Not tainted 4.19.1-rt3 #10
| Call Trace:
|  rt_spin_lock+0x3f/0x50
|  gen6_read32+0x45/0x1d0 [i915]
|  g4x_get_vblank_counter+0x36/0x40 [i915]
|  trace_event_raw_event_i915_pipe_update_start+0x7d/0xf0 [i915]

The tracing events use trace_i915_pipe_update_start() among other events
use functions acquire spin locks. A few trace points use
intel_get_crtc_scanline(), others use ->get_vblank_counter() wich also
might acquire a sleeping lock.

Based on this I don't see any other way than disable trace points on RT.

Cc: stable-rt@vger.kernel.org
Reported-by: Luca Abeni <lucabe72@gmail.com>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
friendlyarm pushed a commit to friendlyarm/kernel-rockchip that referenced this issue Nov 12, 2022
[ Upstream commit 97f88a3 ]

I found a null pointer reference in arch_prepare_kprobe():

  # echo 'p cmdline_proc_show' > kprobe_events
  # echo 'p cmdline_proc_show+16' >> kprobe_events
  Kernel attempted to read user page (0) - exploit attempt? (uid: 0)
  BUG: Kernel NULL pointer dereference on read at 0x00000000
  Faulting instruction address: 0xc000000000050bfc
  Oops: Kernel access of bad area, sig: 11 [#1]
  LE PAGE_SIZE=64K MMU=Radix SMP NR_CPUS=2048 NUMA PowerNV
  Modules linked in:
  CPU: 0 PID: 122 Comm: sh Not tainted 6.0.0-rc3-00007-gdcf8e5633e2e rockchip-linux#10
  NIP:  c000000000050bfc LR: c000000000050bec CTR: 0000000000005bdc
  REGS: c0000000348475b0 TRAP: 0300   Not tainted  (6.0.0-rc3-00007-gdcf8e5633e2e)
  MSR:  9000000000009033 <SF,HV,EE,ME,IR,DR,RI,LE>  CR: 88002444  XER: 20040006
  CFAR: c00000000022d100 DAR: 0000000000000000 DSISR: 40000000 IRQMASK: 0
  ...
  NIP arch_prepare_kprobe+0x10c/0x2d0
  LR  arch_prepare_kprobe+0xfc/0x2d0
  Call Trace:
    0xc0000000012f77a0 (unreliable)
    register_kprobe+0x3c0/0x7a0
    __register_trace_kprobe+0x140/0x1a0
    __trace_kprobe_create+0x794/0x1040
    trace_probe_create+0xc4/0xe0
    create_or_delete_trace_kprobe+0x2c/0x80
    trace_parse_run_command+0xf0/0x210
    probes_write+0x20/0x40
    vfs_write+0xfc/0x450
    ksys_write+0x84/0x140
    system_call_exception+0x17c/0x3a0
    system_call_vectored_common+0xe8/0x278
  --- interrupt: 3000 at 0x7fffa5682de0
  NIP:  00007fffa5682de0 LR: 0000000000000000 CTR: 0000000000000000
  REGS: c000000034847e80 TRAP: 3000   Not tainted  (6.0.0-rc3-00007-gdcf8e5633e2e)
  MSR:  900000000280f033 <SF,HV,VEC,VSX,EE,PR,FP,ME,IR,DR,RI,LE>  CR: 44002408  XER: 00000000

The address being probed has some special:

  cmdline_proc_show: Probe based on ftrace
  cmdline_proc_show+16: Probe for the next instruction at the ftrace location

The ftrace-based kprobe does not generate kprobe::ainsn::insn, it gets
set to NULL. In arch_prepare_kprobe() it will check for:

  ...
  prev = get_kprobe(p->addr - 1);
  preempt_enable_no_resched();
  if (prev && ppc_inst_prefixed(ppc_inst_read(prev->ainsn.insn))) {
  ...

If prev is based on ftrace, 'ppc_inst_read(prev->ainsn.insn)' will occur
with a null pointer reference. At this point prev->addr will not be a
prefixed instruction, so the check can be skipped.

Check if prev is ftrace-based kprobe before reading 'prev->ainsn.insn'
to fix this problem.

Fixes: b4657f7 ("powerpc/kprobes: Don't allow breakpoints on suffixes")
Signed-off-by: Li Huafei <lihuafei1@huawei.com>
[mpe: Trim oops]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220923093253.177298-1-lihuafei1@huawei.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
hejiawencc pushed a commit to LubanCat/kernel that referenced this issue Dec 14, 2022
Luca Abeni reported this:
| BUG: scheduling while atomic: kworker/u8:2/15203/0x00000003
| CPU: 1 PID: 15203 Comm: kworker/u8:2 Not tainted 4.19.1-rt3 rockchip-linux#10
| Call Trace:
|  rt_spin_lock+0x3f/0x50
|  gen6_read32+0x45/0x1d0 [i915]
|  g4x_get_vblank_counter+0x36/0x40 [i915]
|  trace_event_raw_event_i915_pipe_update_start+0x7d/0xf0 [i915]

The tracing events use trace_i915_pipe_update_start() among other events
use functions acquire spin locks. A few trace points use
intel_get_crtc_scanline(), others use ->get_vblank_counter() wich also
might acquire a sleeping lock.

Based on this I don't see any other way than disable trace points on RT.

Cc: stable-rt@vger.kernel.org
Reported-by: Luca Abeni <lucabe72@gmail.com>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
friendlyarm pushed a commit to friendlyarm/kernel-rockchip that referenced this issue Dec 5, 2023
[ Upstream commit a154f5f ]

The following call trace shows a deadlock issue due to recursive locking of
mutex "device_mutex". First lock acquire is in target_for_each_device() and
second in target_free_device().

 PID: 148266   TASK: ffff8be21ffb5d00  CPU: 10   COMMAND: "iscsi_ttx"
  #0 [ffffa2bfc9ec3b18] __schedule at ffffffffa8060e7f
  #1 [ffffa2bfc9ec3ba0] schedule at ffffffffa8061224
  #2 [ffffa2bfc9ec3bb8] schedule_preempt_disabled at ffffffffa80615ee
  #3 [ffffa2bfc9ec3bc8] __mutex_lock at ffffffffa8062fd7
  #4 [ffffa2bfc9ec3c40] __mutex_lock_slowpath at ffffffffa80631d3
  #5 [ffffa2bfc9ec3c50] mutex_lock at ffffffffa806320c
  #6 [ffffa2bfc9ec3c68] target_free_device at ffffffffc0935998 [target_core_mod]
  #7 [ffffa2bfc9ec3c90] target_core_dev_release at ffffffffc092f975 [target_core_mod]
  #8 [ffffa2bfc9ec3ca0] config_item_put at ffffffffa79d250f
  rockchip-linux#9 [ffffa2bfc9ec3cd0] config_item_put at ffffffffa79d2583
 rockchip-linux#10 [ffffa2bfc9ec3ce0] target_devices_idr_iter at ffffffffc0933f3a [target_core_mod]
 rockchip-linux#11 [ffffa2bfc9ec3d00] idr_for_each at ffffffffa803f6fc
 rockchip-linux#12 [ffffa2bfc9ec3d60] target_for_each_device at ffffffffc0935670 [target_core_mod]
 rockchip-linux#13 [ffffa2bfc9ec3d98] transport_deregister_session at ffffffffc0946408 [target_core_mod]
 rockchip-linux#14 [ffffa2bfc9ec3dc8] iscsit_close_session at ffffffffc09a44a6 [iscsi_target_mod]
 rockchip-linux#15 [ffffa2bfc9ec3df0] iscsit_close_connection at ffffffffc09a4a88 [iscsi_target_mod]
 rockchip-linux#16 [ffffa2bfc9ec3df8] finish_task_switch at ffffffffa76e5d07
 rockchip-linux#17 [ffffa2bfc9ec3e78] iscsit_take_action_for_connection_exit at ffffffffc0991c23 [iscsi_target_mod]
 rockchip-linux#18 [ffffa2bfc9ec3ea0] iscsi_target_tx_thread at ffffffffc09a403b [iscsi_target_mod]
 rockchip-linux#19 [ffffa2bfc9ec3f08] kthread at ffffffffa76d8080
 rockchip-linux#20 [ffffa2bfc9ec3f50] ret_from_fork at ffffffffa8200364

Fixes: 36d4cb4 ("scsi: target: Avoid that EXTENDED COPY commands trigger lock inversion")
Signed-off-by: Junxiao Bi <junxiao.bi@oracle.com>
Link: https://lore.kernel.org/r/20230918225848.66463-1-junxiao.bi@oracle.com
Reviewed-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
friendlyarm pushed a commit to friendlyarm/kernel-rockchip that referenced this issue Dec 5, 2023
[ Upstream commit a84fbf2 ]

Generating metrics llc_code_read_mpi_demand_plus_prefetch,
llc_data_read_mpi_demand_plus_prefetch,
llc_miss_local_memory_bandwidth_read,
llc_miss_local_memory_bandwidth_write,
nllc_miss_remote_memory_bandwidth_read, memory_bandwidth_read,
memory_bandwidth_write, uncore_frequency, upi_data_transmit_bw,
C2_Pkg_Residency, C3_Core_Residency, C3_Pkg_Residency,
C6_Core_Residency, C6_Pkg_Residency, C7_Core_Residency,
C7_Pkg_Residency, UNCORE_FREQ and tma_info_system_socket_clks would
trigger an address sanitizer heap-buffer-overflows on a SkylakeX.

```
==2567752==ERROR: AddressSanitizer: heap-buffer-overflow on address 0x5020003ed098 at pc 0x5621a816654e bp 0x7fffb55d4da0 sp 0x7fffb55d4d98
READ of size 4 at 0x5020003eee78 thread T0
    #0 0x558265d6654d in aggr_cpu_id__is_empty tools/perf/util/cpumap.c:694:12
    #1 0x558265c914da in perf_stat__get_aggr tools/perf/builtin-stat.c:1490:6
    #2 0x558265c914da in perf_stat__get_global_cached tools/perf/builtin-stat.c:1530:9
    #3 0x558265e53290 in should_skip_zero_counter tools/perf/util/stat-display.c:947:31
    #4 0x558265e53290 in print_counter_aggrdata tools/perf/util/stat-display.c:985:18
    #5 0x558265e51931 in print_counter tools/perf/util/stat-display.c:1110:3
    #6 0x558265e51931 in evlist__print_counters tools/perf/util/stat-display.c:1571:5
    #7 0x558265c8ec87 in print_counters tools/perf/builtin-stat.c:981:2
    #8 0x558265c8cc71 in cmd_stat tools/perf/builtin-stat.c:2837:3
    rockchip-linux#9 0x558265bb9bd4 in run_builtin tools/perf/perf.c:323:11
    rockchip-linux#10 0x558265bb98eb in handle_internal_command tools/perf/perf.c:377:8
    rockchip-linux#11 0x558265bb9389 in run_argv tools/perf/perf.c:421:2
    rockchip-linux#12 0x558265bb9389 in main tools/perf/perf.c:537:3
```

The issue was the use of testing a cpumap with NULL rather than using
empty, as a map containing the dummy value isn't NULL and the -1
results in an empty aggr map being allocated which legitimately
overflows when any member is accessed.

Fixes: 8a96f45 ("perf stat: Avoid SEGV if core.cpus isn't set")
Signed-off-by: Ian Rogers <irogers@google.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20230906003912.3317462-1-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
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