Dl doc by lucabe72 · Pull Request #1 · jlelli/linux

lucabe72 · 2014-01-27T10:40:29Z

Some documentation improvements for SCHED_DEADLINE, splitting the algorithm description (and guarantee) from the real-time task model (and the discussion about how to properly assign the scheduling parameters in order to respect the job deadlines), and providing a (hopefully) more complete and clear description of the scheduling algorithm.
Admission control is still TBD

The CBS guarantee can only be provided if a proper admission control is enforced... Mention this as early as possible.

"throttled" is more in line with the Linux kernel naming. Anyway, keep a reference to the term commonly used in literature.

___cfg80211_scan_done() can be called in some cases (e.g. on NETDEV_DOWN) before the low level driver notified scan completion (which is indicated by passing leak=true). Clearing rdev->scan_req in this case is buggy, as scan_done_wk might have already being queued/running (and can't be flushed as it takes rtnl()). If a new scan will be requested at this stage, the scan_done_wk will try freeing it (instead of the previous scan), and this will later result in a use after free. Simply remove the "leak" option, and replace it with a standard WARN_ON. An example backtrace after such crash: Unable to handle kernel paging request at virtual address fffffee5 pgd = c0004000 [fffffee5] *pgd=9fdf6821, *pte=00000000, *ppte=00000000 Internal error: Oops: 17 [#1] SMP ARM PC is at cfg80211_scan_done+0x28/0xc4 [cfg80211] LR is at __ieee80211_scan_completed+0xe4/0x2dc [mac80211] [<bf0077b0>] (cfg80211_scan_done+0x28/0xc4 [cfg80211]) [<bf0973d4>] (__ieee80211_scan_completed+0xe4/0x2dc [mac80211]) [<bf0982cc>] (ieee80211_scan_work+0x94/0x4f0 [mac80211]) [<c005fd10>] (process_one_work+0x1b0/0x4a8) [<c0060404>] (worker_thread+0x138/0x37c) [<c0066d70>] (kthread+0xa4/0xb0) Signed-off-by: Eliad Peller <eliad@wizery.com> Signed-off-by: Johannes Berg <johannes.berg@intel.com>

After the previous fix, there still has another ASSERT failure if turning off any type of quota while fsstress is running at the same time. Backtrace in this case: [ 50.867897] XFS: Assertion failed: XFS_IS_GQUOTA_ON(mp), file: fs/xfs/xfs_qm.c, line: 2118 [ 50.867924] ------------[ cut here ]------------ ... <snip> [ 50.867957] Kernel BUG at ffffffffa0b55a32 [verbose debug info unavailable] [ 50.867999] invalid opcode: 0000 [#1] SMP [ 50.869407] Call Trace: [ 50.869446] [<ffffffffa0bc408a>] xfs_qm_vop_create_dqattach+0x19a/0x2d0 [xfs] [ 50.869512] [<ffffffffa0b9cc45>] xfs_create+0x5c5/0x6a0 [xfs] [ 50.869564] [<ffffffffa0b5307c>] xfs_vn_mknod+0xac/0x1d0 [xfs] [ 50.869615] [<ffffffffa0b531d6>] xfs_vn_mkdir+0x16/0x20 [xfs] [ 50.869655] [<ffffffff811becd5>] vfs_mkdir+0x95/0x130 [ 50.869689] [<ffffffff811bf63a>] SyS_mkdirat+0xaa/0xe0 [ 50.869723] [<ffffffff811bf689>] SyS_mkdir+0x19/0x20 [ 50.869757] [<ffffffff8170f7dd>] system_call_fastpath+0x1a/0x1f [ 50.869793] Code: 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 55 48 89 <snip> [ 50.870003] RIP [<ffffffffa0b55a32>] assfail+0x22/0x30 [xfs] [ 50.870050] RSP <ffff88002941fd60> [ 50.879251] ---[ end trace c93a2b342341c65b ]--- We're hitting the ASSERT(XFS_IS_*QUOTA_ON(mp)) in xfs_qm_vop_create_dqattach(), however the assertion itself is not right IMHO. While performing quota off, we firstly clear the XFS_*QUOTA_ACTIVE bit(s) from struct xfs_mount without taking any special locks, see xfs_qm_scall_quotaoff(). Hence there is no guarantee that the desired quota is still active. Signed-off-by: Jie Liu <jeff.liu@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Ben Myers <bpm@sgi.com>

This patches fixes the following warning by replacing smp_processor_id() with raw_smp_processor_id(): [ 11.120893] BUG: using smp_processor_id() in preemptible [00000000] code: arping/3510 [ 11.120913] caller is .packet_sendmsg+0xc14/0xe68 [ 11.120920] CPU: 13 PID: 3510 Comm: arping Not tainted 3.13.0-rc3-next-20131211-dirty #1 [ 11.120926] Call Trace: [ 11.120932] [c0000001f803f6f0] [c0000000000138dc] .show_stack+0x110/0x25c (unreliable) [ 11.120942] [c0000001f803f7e0] [c00000000083dd24] .dump_stack+0xa0/0x37c [ 11.120951] [c0000001f803f870] [c000000000493fd4] .debug_smp_processor_id+0xfc/0x12c [ 11.120959] [c0000001f803f900] [c0000000007eba78] .packet_sendmsg+0xc14/0xe68 [ 11.120968] [c0000001f803fa80] [c000000000700968] .sock_sendmsg+0xa0/0xe0 [ 11.120975] [c0000001f803fbf0] [c0000000007014d8] .SyS_sendto+0x100/0x148 [ 11.120983] [c0000001f803fd60] [c0000000006fff10] .SyS_socketcall+0x1c4/0x2e8 [ 11.120990] [c0000001f803fe30] [c00000000000a1e4] syscall_exit+0x0/0x9c Signed-off-by: Li Zhong <zhong@linux.vnet.ibm.com> Acked-by: Jesper Dangaard Brouer <brouer@redhat.com> Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>

Adding clocks from a kernel module can cause a NULL pointer dereference if the parent of a clock is added after the clock is added. This happens because __clk_init() iterates over the list of orphans and reparents the orphans to the clock being registered before creating the debugfs entry for the clock. Create the debugfs entry first before reparenting the orphans. Unable to handle kernel NULL pointer dereference at virtual address 00000028 pgd = ef3e4000 [00000028] *pgd=bf810831 Internal error: Oops: 17 [#1] PREEMPT SMP ARM Modules linked in: mmcc_8960(+) CPU: 0 PID: 52 Comm: modprobe Not tainted 3.12.0-rc2-00023-g1021a28-dirty #659 task: ef319200 ti: ef3a6000 task.ti: ef3a6000 PC is at lock_rename+0x24/0xc4 LR is at debugfs_rename+0x34/0x208 pc : [<c0317238>] lr : [<c047dfe4>] psr: 00000013 sp : ef3a7b88 ip : ef3a7ba8 fp : ef3a7ba4 r10: ef3d51cc r9 : ef3bc680 r8 : ef3d5210 r7 : ef3bc640 r6 : eee287e r5 : eee287e r4 : 00000000 r3 : ef3bc640 r2 : 00000000 r1 : eee287e r0 : 00000000 Flags: nzcv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user Control: 10c5787d Table: af3e406a DAC: 00000015 Process modprobe (pid: 52, stack limit = 0xef3a6240) Stack: (0xef3a7b88 to 0xef3a8000) 7b80: ef3bc640 ee4047e0 00000000 eee287e ef3a7bec ef3a7ba8 7ba0: c047dfe4 c0317220 ef3bc680 ef3d51cc ef3a7bdc ef3a7bc0 c06e29d0 c0268784 7bc0: c08946e8 ef3d5210 00000000 ef3bc700 ef3d5290 ef3d5210 ef3bc680 ef3d51cc 7be0: ef3a7c0c ef3a7bf0 c05b9e9c c047dfbc 00000000 00000000 ef3d5210 ef3d5290 7c00: ef3a7c24 ef3a7c10 c05baebc c05b9e30 00000001 00000001 ef3a7c64 ef3a7c28 7c20: c05bb124 c05bae9c bf000cd8 ef3bc7c0 000000d0 c0ff129c bf001774 00000002 7c40: ef3bc740 ef3d5290 ef0f9a10 bf001774 bf00042c 00000061 ef3a7c8c ef3a7c68 7c60: c05bb480 c05baed8 bf001774 ef3d5290 ef0f9a10 bf001774 ef38bc10 ef0f9a00 7c80: ef3a7cac ef3a7c90 c05bb5a8 c05bb3a0 bf001774 00000062 ef0f9a10 ef38bc18 7ca0: ef3a7cec ef3a7cb0 bf00010c c05bb56c 00000000 ef38ba00 00000000 ef3d60d0 7cc0: ef3a7cdc c0fefc24 ef0f9a10 c0a091c0 bf000d24 00000000 bf0029f bf006000 7ce0: ef3a7cfc ef3a7cf0 c05156c0 bf00004 ef3a7d2c ef3a7d00 c0513f5c c05156a8 7d00: ef3a7d2c ef0f9a10 ef0f9a10 bf000d24 ef0f9a44 c09ca588 00000000 bf006000 7d20: ef3a7d4c ef3a7d30 c05142b8 c0513ecc ef0fd25c 00000000 bf000d24 c0514214 7d40: ef3a7d74 ef3a7d50 c0512030 c0514220 ef0050a8 ef0fd250 ef0050f bf000d24 7d60: ef37c100 c09ed150 ef3a7d84 ef3a7d78 c05139c8 c0511fd8 ef3a7 7d80: c051344c c05139a8 bf000864 c09ca588 ef3a7db4 bf000d24 bf002 7da0: c09ca588 00000000 ef3a7dcc ef3a7db8 c05149dc c0513360 ef3a7 7dc0: ef3a7ddc ef3a7dd0 c051591 c0514960 ef3a7dec ef3a7de0 bf006 7de0: ef3a7e74 ef3a7df0 c0208800 bf00600c ef3a7e1c ef3a7e00 c04c5 7e00: ffffffff c09d46c4 00000000 bf0029a8 ef3a7e34 ef3a7e20 c024c 7e20: ffffffff c09d46c4 ef3a7e5c ef3a7e38 c024e2fc c024ce40 00000 7e40: ef3a7f48 bf0029b4 bf0029a8 271aeb1c ef3a7f48 bf0029a8 00000001 ef383c00 7e60: bf0029f 00000001 ef3a7f3c ef3a7e78 c028fac4 c0208718 bf0029b4 00007fff 7e80: c028cd58 000000d2 f0065000 00000000 ef3a7ebc 00000000 00000000 bf0029b4 7ea0: 00000000 bf0029a bf0029b4 ef3a6000 ef3a7efc c08bf128 00000000 00000000 7ec0: 00000000 00000000 00000000 00000000 6e72656b 00006c65 00000000 00000000 7ee0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 7f00: 00000000 00000000 00000000 271aeb1c ef3a7f2c 00016376 b6f38008 001d3774 7f20: 00000080 c020f968 ef3a6000 00000000 ef3a7fa4 ef3a7f40 c02904dc c028e178 7f40: c020f898 010ccfa8 f0065000 00016376 f0073f60 f0073d7d f007a1e8 00002b24 7f60: 000039e4 00000000 00000000 00000000 0000002f 00000030 00000019 00000016 7f80: 00000012 00000000 00000000 010de1b2 b6f38008 010ccfa8 00000000 ef3a7fa8 7fa0: c020f6c0 c0290434 010de1b2 b6f38008 b6f38008 00016376 001d3774 00000000 7fc0: 010de1b2 b6f38008 010ccfa8 00000080 010de1b2 bedb6f90 010de1c9 0001d8dc 7fe0: 0000000c bedb674c 0001ce30 000094c4 60000010 b6f38008 00000008 0000001d [<c0317238>] (lock_rename+0x24/0xc4) from [<c047dfe4>] (debugfs_rename+0x34/0x208) [<c047dfe4>] (debugfs_rename+0x34/0x208) from [<c05b9e9c>] (clk_debug_reparent+0x78/0xc0) [<c05baebc>] (__clk_reparent+0x2c/0x3c) from [<c05bb124>] (__clk_init+0x258/0x4c8) [<c05bb124>] (__clk_init+0x258/0x4c8) from [<c05bb480>] (_clk_register+0xec/0x1cc) [<c05bb480>] (_clk_register+0xec/0x1cc) from [<c05bb5a8>] (devm_clk_register+0x48/0x7c) [<c05bb5a8>] (devm_clk_register+0x48/0x7c) from [<bf00010c>] (msm_mmcc_8960_probe+0xd8/0x190 [mmcc_8960]) [<bf00010c>] (msm_mmcc_8960_probe+0xd8/0x190 [mmcc_8960]) from [<c05156c0>] (platform_drv_probe+0x24/0x28) [<c05156c0>] (platform_drv_probe+0x24/0x28) from [<c0513f5c>] (driver_probe_device+0x9c/0x354) [<c0513f5c>] (driver_probe_device+0x9c/0x354) from [<c05142b8>] (__driver_attach+0xa4/0xa8) [<c05142b8>] (__driver_attach+0xa4/0xa8) from [<c0512030>] (bus_for_each_dev+0x64/0x98) [<c0512030>] (bus_for_each_dev+0x64/0x98) from [<c05139c8>] (driver_attach+0x2c/0x30) [<c05139c8>] (driver_attach+0x2c/0x30) from [<c051344c>] (bus_add_driver+0xf8/0x2a8) [<c051344c>] (bus_add_driver+0xf8/0x2a8) from [<c05149dc>] (driver_register+0x88/0x104) [<c05149dc>] (driver_register+0x88/0x104) from [<c0515914>] (__platform_driver_register+0x58/0x6c) [<c0515914>] (__platform_driver_register+0x58/0x6c) from [<bf006018>] (msm_mmcc_8960_driver_init+0x18/0x24 [mmcc_8960]) [<bf006018>] (msm_mmcc_8960_driver_init+0x18/0x24 [mmcc_8960]) from [<c0208800>] (do_one_initcall+0xf4/0x1b8) [<c0208800>] (do_one_initcall+0xf4/0x1b8) from [<c028fac4>] (load_module+0x1958/0x22bc) [<c028fac4>] (load_module+0x1958/0x22bc) from [<c02904dc>] (SyS_init_module+0xb4/0x120) [<c02904dc>] (SyS_init_module+0xb4/0x120) from [<c020f6c0>] (ret_fast_syscall+0x0/0x48) Code: e1500001 e1a04000 e1a05001 0a000021 (e5903028) Signed-off-by: Stephen Boyd <sboyd@codeaurora.org> Signed-off-by: Mike Turquette <mturquette@linaro.org>

iwl_nvm_init() return value wasn't checked in some path, which resulted in the following panic (if there was some issue with the nvm): Unable to handle kernel NULL pointer dereference at virtual address 00000004 pgd = d0460000 [00000004] *pgd=00000000 Internal error: Oops: 5 [#1] PREEMPT SMP Modules linked in: iwlmvm(+) iwlwifi mac80211 cfg80211 compat [last unloaded: compat] PC is at iwl_mvm_mac_setup_register+0x12c/0x460 [iwlmvm] LR is at 0x2710 pc : [<bf50dd4c>] lr : [<00002710>] psr: 20800013 sp : d00cfe18 ip : 0000081e fp : d006b908 r10: d0711408 r9 : bf532e64 r8 : d006b5bc r7 : d01af000 r6 : bf39cefc r5 : d006ab00 r4 : d006b5a4 r3 : 00000001 r2 : 00000000 r1 : d006a120 r0 : d006b860 Signed-off-by: Eliad Peller <eliad@wizery.com> Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>

Command "tcrypt sec=1 mode=403" give the follwoing error for Polling mode: root@am335x-evm:/# insmod tcrypt.ko sec=1 mode=403 [...] [ 346.982754] test 15 ( 4096 byte blocks, 1024 bytes per update, 4 updates): 4352 opers/sec, 17825792 bytes/sec [ 347.992661] test 16 ( 4096 byte blocks, 4096 bytes per update, 1 updates): 7095 opers/sec, 29061120 bytes/sec [ 349.002667] test 17 ( 8192 byte blocks, 16 bytes per update, 512 updates): [ 349.010882] Unable to handle kernel NULL pointer dereference at virtual address 00000000 [ 349.020037] pgd = ddeac000 [ 349.022884] [00000000] *pgd=9dcb4831, *pte=00000000, *ppte=00000000 [ 349.029816] Internal error: Oops: 17 [#1] PREEMPT SMP ARM [ 349.035482] Modules linked in: tcrypt(+) [ 349.039617] CPU: 0 PID: 1473 Comm: insmod Not tainted 3.12.4-01566-g6279006-dirty #38 [ 349.047832] task: dda91540 ti: ddcd2000 task.ti: ddcd2000 [ 349.053517] PC is at omap_sham_xmit_dma+0x6c/0x238 [ 349.058544] LR is at omap_sham_xmit_dma+0x38/0x238 [ 349.063570] pc : [<c04eb7cc>] lr : [<c04eb798>] psr: 20000013 [ 349.063570] sp : ddcd3c78 ip : 00000000 fp : 9d8980b8 [ 349.075610] r10: 00000000 r9 : 00000000 r8 : 00000000 [ 349.081090] r7 : 00001000 r6 : dd898000 r5 : 00000040 r4 : ddb10550 [ 349.087935] r3 : 00000004 r2 : 00000010 r1 : 53100080 r0 : 00000000 [ 349.094783] Flags: nzCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user [ 349.102268] Control: 10c5387d Table: 9deac019 DAC: 00000015 [ 349.108294] Process insmod (pid: 1473, stack limit = 0xddcd2248) [...] This is because polling_mode is not enabled for ctx without FLAGS_FINUP. For polling mode the bufcnt is made 0 unconditionally. But it should be made 0 only if it is a final update or a total is not zero(This condition is similar to what is done in DMA case). Because of this wrong hashes are produced. Fixing the same. Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

The user has the option of disabling the platform driver: 00:02.0 Unassigned class [ff80]: XenSource, Inc. Xen Platform Device (rev 01) which is used to unplug the emulated drivers (IDE, Realtek 8169, etc) and allow the PV drivers to take over. If the user wishes to disable that they can set: xen_platform_pci=0 (in the guest config file) or xen_emul_unplug=never (on the Linux command line) except it does not work properly. The PV drivers still try to load and since the Xen platform driver is not run - and it has not initialized the grant tables, most of the PV drivers stumble upon: input: Xen Virtual Keyboard as /devices/virtual/input/input5 input: Xen Virtual Pointer as /devices/virtual/input/input6M ------------[ cut here ]------------ kernel BUG at /home/konrad/ssd/konrad/linux/drivers/xen/grant-table.c:1206! invalid opcode: 0000 [#1] SMP Modules linked in: xen_kbdfront(+) xenfs xen_privcmd CPU: 6 PID: 1389 Comm: modprobe Not tainted 3.13.0-rc1upstream-00021-ga6c892b-dirty #1 Hardware name: Xen HVM domU, BIOS 4.4-unstable 11/26/2013 RIP: 0010:[<ffffffff813ddc40>] [<ffffffff813ddc40>] get_free_entries+0x2e0/0x300 Call Trace: [<ffffffff8150d9a3>] ? evdev_connect+0x1e3/0x240 [<ffffffff813ddd0e>] gnttab_grant_foreign_access+0x2e/0x70 [<ffffffffa0010081>] xenkbd_connect_backend+0x41/0x290 [xen_kbdfront] [<ffffffffa0010a12>] xenkbd_probe+0x2f2/0x324 [xen_kbdfront] [<ffffffff813e5757>] xenbus_dev_probe+0x77/0x130 [<ffffffff813e7217>] xenbus_frontend_dev_probe+0x47/0x50 [<ffffffff8145e9a9>] driver_probe_device+0x89/0x230 [<ffffffff8145ebeb>] __driver_attach+0x9b/0xa0 [<ffffffff8145eb50>] ? driver_probe_device+0x230/0x230 [<ffffffff8145eb50>] ? driver_probe_device+0x230/0x230 [<ffffffff8145cf1c>] bus_for_each_dev+0x8c/0xb0 [<ffffffff8145e7d9>] driver_attach+0x19/0x20 [<ffffffff8145e260>] bus_add_driver+0x1a0/0x220 [<ffffffff8145f1ff>] driver_register+0x5f/0xf0 [<ffffffff813e55c5>] xenbus_register_driver_common+0x15/0x20 [<ffffffff813e76b3>] xenbus_register_frontend+0x23/0x40 [<ffffffffa0015000>] ? 0xffffffffa0014fff [<ffffffffa001502b>] xenkbd_init+0x2b/0x1000 [xen_kbdfront] [<ffffffff81002049>] do_one_initcall+0x49/0x170 .. snip.. which is hardly nice. This patch fixes this by having each PV driver check for: - if running in PV, then it is fine to execute (as that is their native environment). - if running in HVM, check if user wanted 'xen_emul_unplug=never', in which case bail out and don't load any PV drivers. - if running in HVM, and if PCI device 5853:0001 (xen_platform_pci) does not exist, then bail out and not load PV drivers. - (v2) if running in HVM, and if the user wanted 'xen_emul_unplug=ide-disks', then bail out for all PV devices _except_ the block one. Ditto for the network one ('nics'). - (v2) if running in HVM, and if the user wanted 'xen_emul_unplug=unnecessary' then load block PV driver, and also setup the legacy IDE paths. In (v3) make it actually load PV drivers. Reported-by: Sander Eikelenboom <linux@eikelenboom.it Reported-by: Anthony PERARD <anthony.perard@citrix.com> Reported-and-Tested-by: Fabio Fantoni <fabio.fantoni@m2r.biz> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> [v2: Add extra logic to handle the myrid ways 'xen_emul_unplug' can be used per Ian and Stefano suggestion] [v3: Make the unnecessary case work properly] [v4: s/disks/ide-disks/ spotted by Fabio] Reviewed-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Acked-by: Bjorn Helgaas <bhelgaas@google.com> [for PCI parts] CC: stable@vger.kernel.org

When disconnecting it is possible that the l2cap_conn pointer is already NULL when bt_6lowpan_del_conn() is entered. Looking at l2cap_conn_del also verifies this as there's a NULL check there too. This patch adds the missing NULL check without which the following bug may occur: BUG: unable to handle kernel NULL pointer dereference at (null) IP: [<c131e9c7>] bt_6lowpan_del_conn+0x19/0x12a *pde = 00000000 Oops: 0000 [#1] SMP CPU: 1 PID: 52 Comm: kworker/u5:1 Not tainted 3.12.0+ #196 Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011 Workqueue: hci0 hci_rx_work task: f6259b00 ti: f48c0000 task.ti: f48c0000 EIP: 0060:[<c131e9c7>] EFLAGS: 00010282 CPU: 1 EIP is at bt_6lowpan_del_conn+0x19/0x12a EAX: 00000000 EBX: ef094e10 ECX: 00000000 EDX: 00000016 ESI: 00000000 EDI: f48c1e60 EBP: f48c1e50 ESP: f48c1e34 DS: 007b ES: 007b FS: 00d8 GS: 0000 SS: 0068 CR0: 8005003b CR2: 00000000 CR3: 30c65000 CR4: 00000690 Stack: f4d38000 00000000 f4d38000 00000002 ef094e10 00000016 f48c1e60 f48c1e70 c1316bed f48c1e84 c1316bed 00000000 00000001 ef094e10 f48c1e84 f48c1ed0 c1303cc6 c1303c7 f31f331a c1303cc6 f6e7d1c0 f3f8ea1 f3f8f380 f4d38008 Call Trace: [<c1316bed>] l2cap_disconn_cfm+0x3f/0x5b [<c1316bed>] ? l2cap_disconn_cfm+0x3f/0x5b [<c1303cc6>] hci_event_packet+0x645/0x2117 [<c1303c7b>] ? hci_event_packet+0x5fa/0x2117 [<c1303cc6>] ? hci_event_packet+0x645/0x2117 [<c12681bd>] ? __kfree_skb+0x65/0x68 [<c12681eb>] ? kfree_skb+0x2b/0x2e [<c130d3fb>] ? hci_send_to_sock+0x18d/0x199 [<c12fa327>] hci_rx_work+0xf9/0x295 [<c12fa327>] ? hci_rx_work+0xf9/0x295 [<c1036d25>] process_one_work+0x128/0x1df [<c1346a39>] ? _raw_spin_unlock_irq+0x8/0x12 [<c1036d25>] ? process_one_work+0x128/0x1df [<c103713a>] worker_thread+0x127/0x1c4 [<c1037013>] ? rescuer_thread+0x216/0x216 [<c103aec6>] kthread+0x88/0x8d [<c1040000>] ? task_rq_lock+0x37/0x6e [<c13474b7>] ret_from_kernel_thread+0x1b/0x28 [<c103ae3e>] ? __kthread_parkme+0x50/0x50 Code: 05 b8 f4 ff ff ff 8d 65 f4 5b 5e 5f 5d 8d 67 f8 5f c3 57 8d 7c 24 08 83 e4 f8 ff 77 fc 55 89 e5 57 56f EIP: [<c131e9c7>] bt_6lowpan_del_conn+0x19/0x12a SS:ESP 0068:f48c1e34 CR2: 0000000000000000 Signed-off-by: Johan Hedberg <johan.hedberg@intel.com> Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

Upon unload of the brcmfmac driver it gave a kernel warning because cfg80211 still believed to be connected to an AP. The brcmfmac had already transitioned to disconnected state during unload. This patch adds informing cfg80211 about this transition. This will get rid of warning from cfg80211 seen upon module unload: ------------[ cut here ]------------ WARNING: CPU: 3 PID: 24303 at net/wireless/core.c:952 cfg80211_netdev_notifier_call+0x193/0x640 [cfg80211]() Modules linked in: brcmfmac(O-) brcmutil(O) cfg80211(O) ... [last unloaded: bcma] CPU: 3 PID: 24303 Comm: rmmod Tainted: G W O 3.13.0-rc4-wl-testing-x64-00002-gb472b6d-dirty #1 Hardware name: Dell Inc. Latitude E6410/07XJP9, BIOS A07 02/15/2011 00000000000003b8 ffff8800b211faf8 ffffffff815a7fcd 0000000000000007 0000000000000000 ffff8800b211fb38 ffffffff8104819c ffff880000000000 ffff8800c889d008 ffff8800b2000220 ffff8800c889a000 ffff8800c889d018 Call Trace: [<ffffffff815a7fcd>] dump_stack+0x46/0x58 [<ffffffff8104819c>] warn_slowpath_common+0x8c/0xc0 [<ffffffff810481ea>] warn_slowpath_null+0x1a/0x20 [<ffffffffa173fd83>] cfg80211_netdev_notifier_call+0x193/0x640 [cfg80211] [<ffffffff81521ca8>] ? arp_ifdown+0x18/0x20 [<ffffffff8152d75a>] ? fib_disable_ip+0x3a/0x50 [<ffffffff815b143d>] notifier_call_chain+0x4d/0x70 [<ffffffff8106d6e6>] raw_notifier_call_chain+0x16/0x20 [<ffffffff814b9ae0>] call_netdevice_notifiers_info+0x40/0x70 [<ffffffff814b9b26>] call_netdevice_notifiers+0x16/0x20 [<ffffffff814bb59d>] rollback_registered_many+0x17d/0x280 [<ffffffff814bb74d>] rollback_registered+0x2d/0x40 [<ffffffff814bb7c8>] unregister_netdevice_queue+0x68/0xd0 [<ffffffff814bb9c0>] unregister_netdev+0x20/0x30 [<ffffffffa180069e>] brcmf_del_if+0xce/0x180 [brcmfmac] [<ffffffffa1800b3c>] brcmf_detach+0x6c/0xe0 [brcmfmac] Reviewed-by: Hante Meuleman <meuleman@broadcom.com> Reviewed-by: Pieter-Paul Giesberts <pieterpg@broadcom.com> Signed-off-by: Arend van Spriel <arend@broadcom.com> Signed-off-by: John W. Linville <linville@tuxdriver.com>

Jon Maloy says: ==================== tipc: link setup and failover improvements This series consists of four unrelated commits with different purposes. - Commit #1 is purely cosmetic and pedagogic, hopefully making the failover/tunneling logics slightly easier to understand. - Commit #2 fixes a bug that has always been in the code, but was not discovered until very recently. - Commit #3 fixes a non-fatal race issue in the neighbour discovery code. - Commit #4 removes an unnecessary indirection step during link startup. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>

Sometimes we may meet the following lockdep issue. The root cause is .set_clock callback is executed with spin_lock_irqsave in sdhci_do_set_ios. However, the IMX set_clock callback will try to access clk_get_rate which is using a mutex lock. The fix avoids access mutex in .set_clock callback by initializing the pltfm_host->clock at probe time and use it later instead of calling clk_get_rate again in atomic context. [ INFO: HARDIRQ-safe -> HARDIRQ-unsafe lock order detected ] 3.13.0-rc1+ #285 Not tainted ------------------------------------------------------ kworker/u8:1/29 [HC0[0]:SC0[0]:HE0:SE1] is trying to acquire: (prepare_lock){+.+...}, at: [<80480b08>] clk_prepare_lock+0x44/0xe4 and this task is already holding: (&(&host->lock)->rlock#2){-.-...}, at: [<804611f4>] sdhci_do_set_ios+0x20/0x720 which would create a new lock dependency: (&(&host->lock)->rlock#2){-.-...} -> (prepare_lock){+.+...} but this new dependency connects a HARDIRQ-irq-safe lock: (&(&host->lock)->rlock#2){-.-...} ... which became HARDIRQ-irq-safe at: [<8005f030>] mark_lock+0x140/0x6ac [<80060760>] __lock_acquire+0xb30/0x1cbc [<800620d0>] lock_acquire+0x70/0x84 [<8061d2f0>] _raw_spin_lock+0x30/0x40 [<80460668>] sdhci_irq+0x24/0xa68 [<8006b1d4>] handle_irq_event_percpu+0x54/0x18c [<8006b350>] handle_irq_event+0x44/0x64 [<8006e50c>] handle_fasteoi_irq+0xa0/0x170 [<8006a8f0>] generic_handle_irq+0x30/0x44 [<8000f238>] handle_IRQ+0x54/0xbc [<8000864c>] gic_handle_irq+0x30/0x64 [<80013024>] __irq_svc+0x44/0x5c [<80614c58>] printk+0x38/0x40 [<804622a8>] sdhci_add_host+0x844/0xbcc [<80464948>] sdhci_esdhc_imx_probe+0x378/0x67c [<8032ee88>] platform_drv_probe+0x20/0x50 [<8032d48c>] driver_probe_device+0x118/0x234 [<8032d690>] __driver_attach+0x9c/0xa0 [<8032b89c>] bus_for_each_dev+0x68/0x9c [<8032cf44>] driver_attach+0x20/0x28 [<8032cbc8>] bus_add_driver+0x148/0x1f4 [<8032dce0>] driver_register+0x80/0x100 [<8032ee54>] __platform_driver_register+0x50/0x64 [<8084b094>] sdhci_esdhc_imx_driver_init+0x18/0x20 [<80008980>] do_one_initcall+0x108/0x16c [<8081cca4>] kernel_init_freeable+0x10c/0x1d0 [<80611c50>] kernel_init+0x10/0x120 [<8000e9c8>] ret_from_fork+0x14/0x2c to a HARDIRQ-irq-unsafe lock: (prepare_lock){+.+...} ... which became HARDIRQ-irq-unsafe at: ... [<8005f030>] mark_lock+0x140/0x6ac [<8005f604>] mark_held_locks+0x68/0x12c [<8005f780>] trace_hardirqs_on_caller+0xb8/0x1d8 [<8005f8b4>] trace_hardirqs_on+0x14/0x18 [<8061a130>] mutex_trylock+0x180/0x20c [<80480ad8>] clk_prepare_lock+0x14/0xe4 [<804816a4>] clk_notifier_register+0x28/0xf0 [<80015120>] twd_clk_init+0x50/0x68 [<80008980>] do_one_initcall+0x108/0x16c [<8081cca4>] kernel_init_freeable+0x10c/0x1d0 [<80611c50>] kernel_init+0x10/0x120 [<8000e9c8>] ret_from_fork+0x14/0x2c other info that might help us debug this: Possible interrupt unsafe locking scenario: CPU0 CPU1 ---- ---- lock(prepare_lock); local_irq_disable(); lock(&(&host->lock)->rlock#2); lock(prepare_lock); <Interrupt> lock(&(&host->lock)->rlock#2); *** DEADLOCK *** 3 locks held by kworker/u8:1/29: #0: (kmmcd){.+.+.+}, at: [<8003db18>] process_one_work+0x128/0x468 #1: ((&(&host->detect)->work)){+.+.+.}, at: [<8003db18>] process_one_work+0x128/0x468 #2: (&(&host->lock)->rlock#2){-.-...}, at: [<804611f4>] sdhci_do_set_ios+0x20/0x720 the dependencies between HARDIRQ-irq-safe lock and the holding lock: -> (&(&host->lock)->rlock#2){-.-...} ops: 330 { IN-HARDIRQ-W at: [<8005f030>] mark_lock+0x140/0x6ac [<80060760>] __lock_acquire+0xb30/0x1cbc [<800620d0>] lock_acquire+0x70/0x84 [<8061d2f0>] _raw_spin_lock+0x30/0x40 [<80460668>] sdhci_irq+0x24/0xa68 [<8006b1d4>] handle_irq_event_percpu+0x54/0x18c [<8006b350>] handle_irq_event+0x44/0x64 [<8006e50c>] handle_fasteoi_irq+0xa0/0x170 [<8006a8f0>] generic_handle_irq+0x30/0x44 [<8000f238>] handle_IRQ+0x54/0xbc [<8000864c>] gic_handle_irq+0x30/0x64 [<80013024>] __irq_svc+0x44/0x5c [<80614c58>] printk+0x38/0x40 [<804622a8>] sdhci_add_host+0x844/0xbcc [<80464948>] sdhci_esdhc_imx_probe+0x378/0x67c [<8032ee88>] platform_drv_probe+0x20/0x50 [<8032d48c>] driver_probe_device+0x118/0x234 [<8032d690>] __driver_attach+0x9c/0xa0 [<8032b89c>] bus_for_each_dev+0x68/0x9c [<8032cf44>] driver_attach+0x20/0x28 [<8032cbc8>] bus_add_driver+0x148/0x1f4 [<8032dce0>] driver_register+0x80/0x100 [<8032ee54>] __platform_driver_register+0x50/0x64 [<8084b094>] sdhci_esdhc_imx_driver_init+0x18/0x20 [<80008980>] do_one_initcall+0x108/0x16c [<8081cca4>] kernel_init_freeable+0x10c/0x1d0 [<80611c50>] kernel_init+0x10/0x120 [<8000e9c8>] ret_from_fork+0x14/0x2c IN-SOFTIRQ-W at: [<8005f030>] mark_lock+0x140/0x6ac [<80060204>] __lock_acquire+0x5d4/0x1cbc [<800620d0>] lock_acquire+0x70/0x84 [<8061d40c>] _raw_spin_lock_irqsave+0x40/0x54 [<8045e4a4>] sdhci_tasklet_finish+0x1c/0x120 [<8002b538>] tasklet_action+0xa0/0x15c [<8002b778>] __do_softirq+0x118/0x290 [<8002bcf4>] irq_exit+0xb4/0x10c [<8000f240>] handle_IRQ+0x5c/0xbc [<8000864c>] gic_handle_irq+0x30/0x64 [<80013024>] __irq_svc+0x44/0x5c [<80614c58>] printk+0x38/0x40 [<804622a8>] sdhci_add_host+0x844/0xbcc [<80464948>] sdhci_esdhc_imx_probe+0x378/0x67c [<8032ee88>] platform_drv_probe+0x20/0x50 [<8032d48c>] driver_probe_device+0x118/0x234 [<8032d690>] __driver_attach+0x9c/0xa0 [<8032b89c>] bus_for_each_dev+0x68/0x9c [<8032cf44>] driver_attach+0x20/0x28 [<8032cbc8>] bus_add_driver+0x148/0x1f4 [<8032dce0>] driver_register+0x80/0x100 [<8032ee54>] __platform_driver_register+0x50/0x64 [<8084b094>] sdhci_esdhc_imx_driver_init+0x18/0x20 [<80008980>] do_one_initcall+0x108/0x16c [<8081cca4>] kernel_init_freeable+0x10c/0x1d0 [<80611c50>] kernel_init+0x10/0x120 [<8000e9c8>] ret_from_fork+0x14/0x2c INITIAL USE at: [<8005f030>] mark_lock+0x140/0x6ac [<8005ff0c>] __lock_acquire+0x2dc/0x1cbc [<800620d0>] lock_acquire+0x70/0x84 [<8061d40c>] _raw_spin_lock_irqsave+0x40/0x54 [<804611f4>] sdhci_do_set_ios+0x20/0x720 [<80461924>] sdhci_set_ios+0x30/0x3c [<8044cea0>] mmc_power_up+0x6c/0xd0 [<8044dac4>] mmc_start_host+0x60/0x70 [<8044eb3c>] mmc_add_host+0x60/0x88 [<8046225c>] sdhci_add_host+0x7f8/0xbcc [<80464948>] sdhci_esdhc_imx_probe+0x378/0x67c [<8032ee88>] platform_drv_probe+0x20/0x50 [<8032d48c>] driver_probe_device+0x118/0x234 [<8032d690>] __driver_attach+0x9c/0xa0 [<8032b89c>] bus_for_each_dev+0x68/0x9c [<8032cf44>] driver_attach+0x20/0x28 [<8032cbc8>] bus_add_driver+0x148/0x1f4 [<8032dce0>] driver_register+0x80/0x100 [<8032ee54>] __platform_driver_register+0x50/0x64 [<8084b094>] sdhci_esdhc_imx_driver_init+0x18/0x20 [<80008980>] do_one_initcall+0x108/0x16c [<8081cca4>] kernel_init_freeable+0x10c/0x1d0 [<80611c50>] kernel_init+0x10/0x120 [<8000e9c8>] ret_from_fork+0x14/0x2c } ... key at: [<80e040e8>] __key.26952+0x0/0x8 ... acquired at: [<8005eb60>] check_usage+0x3d0/0x5c0 [<8005edac>] check_irq_usage+0x5c/0xb8 [<80060d38>] __lock_acquire+0x1108/0x1cbc [<800620d0>] lock_acquire+0x70/0x84 [<8061a210>] mutex_lock_nested+0x54/0x3c0 [<80480b08>] clk_prepare_lock+0x44/0xe4 [<8048188c>] clk_get_rate+0x14/0x64 [<8046374c>] esdhc_pltfm_set_clock+0x20/0x2a4 [<8045d70c>] sdhci_set_clock+0x4c/0x498 [<80461518>] sdhci_do_set_ios+0x344/0x720 [<80461924>] sdhci_set_ios+0x30/0x3c [<8044c390>] __mmc_set_clock+0x44/0x60 [<8044cd4c>] mmc_set_clock+0x10/0x14 [<8044f8f4>] mmc_init_card+0x1b4/0x1520 [<80450f00>] mmc_attach_mmc+0xb4/0x194 [<8044da08>] mmc_rescan+0x294/0x2f0 [<8003db94>] process_one_work+0x1a4/0x468 [<8003e850>] worker_thread+0x118/0x3e0 [<80044de0>] kthread+0xd4/0xf0 [<8000e9c8>] ret_from_fork+0x14/0x2c the dependencies between the lock to be acquired and HARDIRQ-irq-unsafe lock: -> (prepare_lock){+.+...} ops: 395 { HARDIRQ-ON-W at: [<8005f030>] mark_lock+0x140/0x6ac [<8005f604>] mark_held_locks+0x68/0x12c [<8005f780>] trace_hardirqs_on_caller+0xb8/0x1d8 [<8005f8b4>] trace_hardirqs_on+0x14/0x18 [<8061a130>] mutex_trylock+0x180/0x20c [<80480ad8>] clk_prepare_lock+0x14/0xe4 [<804816a4>] clk_notifier_register+0x28/0xf0 [<80015120>] twd_clk_init+0x50/0x68 [<80008980>] do_one_initcall+0x108/0x16c [<8081cca4>] kernel_init_freeable+0x10c/0x1d0 [<80611c50>] kernel_init+0x10/0x120 [<8000e9c8>] ret_from_fork+0x14/0x2c SOFTIRQ-ON-W at: [<8005f030>] mark_lock+0x140/0x6ac [<8005f604>] mark_held_locks+0x68/0x12c [<8005f7c8>] trace_hardirqs_on_caller+0x100/0x1d8 [<8005f8b4>] trace_hardirqs_on+0x14/0x18 [<8061a130>] mutex_trylock+0x180/0x20c [<80480ad8>] clk_prepare_lock+0x14/0xe4 [<804816a4>] clk_notifier_register+0x28/0xf0 [<80015120>] twd_clk_init+0x50/0x68 [<80008980>] do_one_initcall+0x108/0x16c [<8081cca4>] kernel_init_freeable+0x10c/0x1d0 [<80611c50>] kernel_init+0x10/0x120 [<8000e9c8>] ret_from_fork+0x14/0x2c INITIAL USE at: [<8005f030>] mark_lock+0x140/0x6ac [<8005ff0c>] __lock_acquire+0x2dc/0x1cbc [<800620d0>] lock_acquire+0x70/0x84 [<8061a0c8>] mutex_trylock+0x118/0x20c [<80480ad8>] clk_prepare_lock+0x14/0xe4 [<80482af8>] __clk_init+0x1c/0x45c [<8048306c>] _clk_register+0xd0/0x170 [<80483148>] clk_register+0x3c/0x7c [<80483b4c>] clk_register_fixed_rate+0x88/0xd8 [<80483c04>] of_fixed_clk_setup+0x68/0x94 [<8084c6fc>] of_clk_init+0x44/0x68 [<808202b0>] time_init+0x2c/0x38 [<8081ca14>] start_kernel+0x1e4/0x368 [<10008074>] 0x10008074 } ... key at: [<808afebc>] prepare_lock+0x38/0x48 ... acquired at: [<8005eb94>] check_usage+0x404/0x5c0 [<8005edac>] check_irq_usage+0x5c/0xb8 [<80060d38>] __lock_acquire+0x1108/0x1cbc [<800620d0>] lock_acquire+0x70/0x84 [<8061a210>] mutex_lock_nested+0x54/0x3c0 [<80480b08>] clk_prepare_lock+0x44/0xe4 [<8048188c>] clk_get_rate+0x14/0x64 [<8046374c>] esdhc_pltfm_set_clock+0x20/0x2a4 [<8045d70c>] sdhci_set_clock+0x4c/0x498 [<80461518>] sdhci_do_set_ios+0x344/0x720 [<80461924>] sdhci_set_ios+0x30/0x3c [<8044c390>] __mmc_set_clock+0x44/0x60 [<8044cd4c>] mmc_set_clock+0x10/0x14 [<8044f8f4>] mmc_init_card+0x1b4/0x1520 [<80450f00>] mmc_attach_mmc+0xb4/0x194 [<8044da08>] mmc_rescan+0x294/0x2f0 [<8003db94>] process_one_work+0x1a4/0x468 [<8003e850>] worker_thread+0x118/0x3e0 [<80044de0>] kthread+0xd4/0xf0 [<8000e9c8>] ret_from_fork+0x14/0x2c stack backtrace: CPU: 2 PID: 29 Comm: kworker/u8:1 Not tainted 3.13.0-rc1+ #285 Workqueue: kmmcd mmc_rescan Backtrace: [<80012160>] (dump_backtrace+0x0/0x10c) from [<80012438>] (show_stack+0x18/0x1c) r6:00000000 r5:00000000 r4:8088ecc8 r3:bfa11200 [<80012420>] (show_stack+0x0/0x1c) from [<80616b14>] (dump_stack+0x84/0x9c) [<80616a90>] (dump_stack+0x0/0x9c) from [<8005ebb4>] (check_usage+0x424/0x5c0) r5:80979940 r4:bfa29b44 [<8005e790>] (check_usage+0x0/0x5c0) from [<8005edac>] (check_irq_usage+0x5c/0xb8) [<8005ed50>] (check_irq_usage+0x0/0xb8) from [<80060d38>] (__lock_acquire+0x1108/0x1cbc) r8:bfa115e8 r7:80df9884 r6:80dafa9c r5:00000003 r4:bfa115d0 [<8005fc30>] (__lock_acquire+0x0/0x1cbc) from [<800620d0>] (lock_acquire+0x70/0x84) [<80062060>] (lock_acquire+0x0/0x84) from [<8061a210>] (mutex_lock_nested+0x54/0x3c0) r7:bfa11200 r6:80dafa9c r5:00000000 r4:80480b08 [<8061a1bc>] (mutex_lock_nested+0x0/0x3c0) from [<80480b08>] (clk_prepare_lock+0x44/0xe4) [<80480ac4>] (clk_prepare_lock+0x0/0xe4) from [<8048188c>] (clk_get_rate+0x14/0x64) r6:03197500 r5:bf0e9aa8 r4:bf827400 r3:808ae128 [<80481878>] (clk_get_rate+0x0/0x64) from [<8046374c>] (esdhc_pltfm_set_clock+0x20/0x2a4) r5:bf0e9aa8 r4:bf0e9c40 [<8046372c>] (esdhc_pltfm_set_clock+0x0/0x2a4) from [<8045d70c>] (sdhci_set_clock+0x4c/0x498) [<8045d6c0>] (sdhci_set_clock+0x0/0x498) from [<80461518>] (sdhci_do_set_ios+0x344/0x720) r8:0000003b r7:20000113 r6:bf0e9d68 r5:bf0e9aa8 r4:bf0e9c40 r3:00000000 [<804611d4>] (sdhci_do_set_ios+0x0/0x720) from [<80461924>] (sdhci_set_ios+0x30/0x3c) r9:00000004 r8:bf131000 r7:bf131048 r6:00000000 r5:bf0e9aa8 r4:bf0e9800 [<804618f4>] (sdhci_set_ios+0x0/0x3c) from [<8044c390>] (__mmc_set_clock+0x44/0x60) r5:03197500 r4:bf0e9800 [<8044c34c>] (__mmc_set_clock+0x0/0x60) from [<8044cd4c>] (mmc_set_clock+0x10/0x14) r5:00000000 r4:bf0e9800 [<8044cd3c>] (mmc_set_clock+0x0/0x14) from [<8044f8f4>] (mmc_init_card+0x1b4/0x1520) [<8044f740>] (mmc_init_card+0x0/0x1520) from [<80450f00>] (mmc_attach_mmc+0xb4/0x194) [<80450e4c>] (mmc_attach_mmc+0x0/0x194) from [<8044da08>] (mmc_rescan+0x294/0x2f0) r5:8065f358 r4:bf0e9af8 [<8044d774>] (mmc_rescan+0x0/0x2f0) from [<8003db94>] (process_one_work+0x1a4/0x468) r8:00000000 r7:bfa29eb0 r6:bf80dc00 r5:bf0e9af8 r4:bf9e3f00 r3:8044d774 [<8003d9f0>] (process_one_work+0x0/0x468) from [<8003e850>] (worker_thread+0x118/0x3e0) [<8003e738>] (worker_thread+0x0/0x3e0) from [<80044de0>] (kthread+0xd4/0xf0) [<80044d0c>] (kthread+0x0/0xf0) from [<8000e9c8>] (ret_from_fork+0x14/0x2c) r7:00000000 r6:00000000 r5:80044d0c r4:bf9e7f00 Fixes: 0ddf03c mmc: esdhc-imx: parse max-frequency from devicetree Signed-off-by: Dong Aisheng <b29396@freescale.com> Acked-by: Shawn Guo <shawn.guo@linaro.org> Tested-by: Philippe De Muyter <phdm@macqel.be> Cc: stable <stable@vger.kernel.org> # 3.13 Signed-off-by: Chris Ball <chris@printf.net>

In https://bugzilla.kernel.org/show_bug.cgi?id=67561, a locking dependency is reported when b43 is used with hostapd, and rfkill is used to kill the radio output. The lockdep splat (in part) is as follows: ====================================================== [ INFO: possible circular locking dependency detected ] 3.12.0 #1 Not tainted ------------------------------------------------------- rfkill/10040 is trying to acquire lock: (rtnl_mutex){+.+.+.}, at: [<ffffffff8146f282>] rtnl_lock+0x12/0x20 but task is already holding lock: (rfkill_global_mutex){+.+.+.}, at: [<ffffffffa04832ca>] rfkill_fop_write+0x6a/0x170 [rfkill] --snip-- Chain exists of: rtnl_mutex --> misc_mtx --> rfkill_global_mutex The fix is to move the initialization of the hardware random number generator outside the code range covered by the rtnl_mutex. Reported-by: yury <urykhy@gmail.com> Tested-by: yury <urykhy@gmail.com> Signed-off-by: Larry Finger <Larry.Finger@lwfinger.net> Cc: Stable <stable@vger.kernel.org> Signed-off-by: John W. Linville <linville@tuxdriver.com>

Paul Durrant says: ==================== make skb_checksum_setup generally available Both xen-netfront and xen-netback need to be able to set up the partial checksum offset of an skb and may also need to recalculate the pseudo- header checksum in the process. This functionality is currently private and duplicated between the two drivers. Patch #1 of this series moves the implementation into the core network code as there is nothing xen-specific about it and it is potentially useful to any network driver. Patch #2 removes the private implementation from netback. Patch #3 removes the private implementation from netfront. v2: - Put skb_checksum_setup in skbuff.c rather than dev.c - remove inline ==================== Signed-off-by: David S. Miller <davem@davemloft.net>

When booting a kexec/kdump kernel on a system that has specific memory hotplug regions the boot will fail with warnings like: swapper/0: page allocation failure: order:9, mode:0x84d0 CPU: 0 PID: 1 Comm: swapper/0 Not tainted 3.10.0-65.el7.x86_64 #1 Hardware name: QCI QSSC-S4R/QSSC-S4R, BIOS QSSC-S4R.QCI.01.00.S013.032920111005 03/29/2011 0000000000000000 ffff8800341bd8c8 ffffffff815bcc67 ffff8800341bd950 ffffffff8113b1a0 ffff880036339b00 0000000000000009 00000000000084d0 ffff8800341bd950 ffffffff815b87ee 0000000000000000 0000000000000200 Call Trace: [<ffffffff815bcc67>] dump_stack+0x19/0x1b [<ffffffff8113b1a0>] warn_alloc_failed+0xf0/0x160 [<ffffffff815b87ee>] ? __alloc_pages_direct_compact+0xac/0x196 [<ffffffff8113f14f>] __alloc_pages_nodemask+0x7ff/0xa00 [<ffffffff815b417c>] vmemmap_alloc_block+0x62/0xba [<ffffffff815b41e9>] vmemmap_alloc_block_buf+0x15/0x3b [<ffffffff815b1ff6>] vmemmap_populate+0xb4/0x21b [<ffffffff815b461d>] sparse_mem_map_populate+0x27/0x35 [<ffffffff815b400f>] sparse_add_one_section+0x7a/0x185 [<ffffffff815a1e9f>] __add_pages+0xaf/0x240 [<ffffffff81047359>] arch_add_memory+0x59/0xd0 [<ffffffff815a21d9>] add_memory+0xb9/0x1b0 [<ffffffff81333b9c>] acpi_memory_device_add+0x18d/0x26d [<ffffffff81309a01>] acpi_bus_device_attach+0x7d/0xcd [<ffffffff8132379d>] acpi_ns_walk_namespace+0xc8/0x17f [<ffffffff81309984>] ? acpi_bus_type_and_status+0x90/0x90 [<ffffffff81309984>] ? acpi_bus_type_and_status+0x90/0x90 [<ffffffff81323c8c>] acpi_walk_namespace+0x95/0xc5 [<ffffffff8130a6d6>] acpi_bus_scan+0x8b/0x9d [<ffffffff81a2019a>] acpi_scan_init+0x63/0x160 [<ffffffff81a1ffb5>] acpi_init+0x25d/0x2a6 [<ffffffff81a1fd58>] ? acpi_sleep_proc_init+0x2a/0x2a [<ffffffff810020e2>] do_one_initcall+0xe2/0x190 [<ffffffff819e20c4>] kernel_init_freeable+0x17c/0x207 [<ffffffff819e18d0>] ? do_early_param+0x88/0x88 [<ffffffff8159fea0>] ? rest_init+0x80/0x80 [<ffffffff8159feae>] kernel_init+0xe/0x180 [<ffffffff815cca2c>] ret_from_fork+0x7c/0xb0 [<ffffffff8159fea0>] ? rest_init+0x80/0x80 Mem-Info: Node 0 DMA per-cpu: CPU 0: hi: 0, btch: 1 usd: 0 Node 0 DMA32 per-cpu: CPU 0: hi: 42, btch: 7 usd: 0 active_anon:0 inactive_anon:0 isolated_anon:0 active_file:0 inactive_file:0 isolated_file:0 unevictable:0 dirty:0 writeback:0 unstable:0 free:872 slab_reclaimable:13 slab_unreclaimable:1880 mapped:0 shmem:0 pagetables:0 bounce:0 free_cma:0 because the system has run out of memory at boot time. This occurs because of the following sequence in the boot: Main kernel boots and sets E820 map. The second kernel is booted with a map generated by the kdump service using memmap= and memmap=exactmap. These parameters are added to the kernel parameters of the kexec/kdump kernel. The kexec/kdump kernel has limited memory resources so as not to severely impact the main kernel. The system then panics and the kdump/kexec kernel boots (which is a completely new kernel boot). During this boot ACPI is initialized and the kernel (as can be seen above) traverses the ACPI namespace and finds an entry for a memory device to be hotadded. ie) [<ffffffff815a1e9f>] __add_pages+0xaf/0x240 [<ffffffff81047359>] arch_add_memory+0x59/0xd0 [<ffffffff815a21d9>] add_memory+0xb9/0x1b0 [<ffffffff81333b9c>] acpi_memory_device_add+0x18d/0x26d [<ffffffff81309a01>] acpi_bus_device_attach+0x7d/0xcd [<ffffffff8132379d>] acpi_ns_walk_namespace+0xc8/0x17f [<ffffffff81309984>] ? acpi_bus_type_and_status+0x90/0x90 [<ffffffff81309984>] ? acpi_bus_type_and_status+0x90/0x90 [<ffffffff81323c8c>] acpi_walk_namespace+0x95/0xc5 [<ffffffff8130a6d6>] acpi_bus_scan+0x8b/0x9d [<ffffffff81a2019a>] acpi_scan_init+0x63/0x160 [<ffffffff81a1ffb5>] acpi_init+0x25d/0x2a6 At this point the kernel adds page table information and the the kexec/kdump kernel runs out of memory. This can also be reproduced by using the memmap=exactmap and mem=X parameters on the main kernel and booting. This patchset resolves the problem by adding a kernel parameter, acpi_no_memhotplug, to disable ACPI memory hotplug. Signed-off-by: Prarit Bhargava <prarit@redhat.com> Acked-by: Vivek Goyal <vgoyal@redhat.com> Acked-by: Toshi Kani <toshi.kani@hp.com> Acked-by: David Rientjes <rientjes@google.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

The sdhci_execute_tuning routine gets lock separately by disable_irq(host->irq); spin_lock(&host->lock); It will cause the following lockdep error message since the &host->lock could also be got in irq context. Use spin_lock_irqsave/spin_unlock_restore instead to get rid of this error message. [ INFO: inconsistent lock state ] 3.13.0-rc1+ #287 Not tainted --------------------------------- inconsistent {IN-HARDIRQ-W} -> {HARDIRQ-ON-W} usage. kworker/u2:1/33 [HC0[0]:SC0[0]:HE1:SE1] takes: (&(&host->lock)->rlock){?.-...}, at: [<8045f7f4>] sdhci_execute_tuning+0x4c/0x710 {IN-HARDIRQ-W} state was registered at: [<8005f030>] mark_lock+0x140/0x6ac [<80060760>] __lock_acquire+0xb30/0x1cbc [<800620d0>] lock_acquire+0x70/0x84 [<8061d1c8>] _raw_spin_lock+0x30/0x40 [<804605cc>] sdhci_irq+0x24/0xa68 [<8006b1d4>] handle_irq_event_percpu+0x54/0x18c [<8006b350>] handle_irq_event+0x44/0x64 [<8006e50c>] handle_fasteoi_irq+0xa0/0x170 [<8006a8f0>] generic_handle_irq+0x30/0x44 [<8000f238>] handle_IRQ+0x54/0xbc [<8000864c>] gic_handle_irq+0x30/0x64 [<80013024>] __irq_svc+0x44/0x5c [<80329bf4>] dev_vprintk_emit+0x50/0x58 [<80329c24>] dev_printk_emit+0x28/0x30 [<80329fec>] __dev_printk+0x4c/0x90 [<8032a180>] dev_err+0x3c/0x48 [<802dd4f0>] _regulator_get+0x158/0x1cc [<802dd5b4>] regulator_get_optional+0x18/0x1c [<80461df4>] sdhci_add_host+0x42c/0xbd8 [<80464820>] sdhci_esdhc_imx_probe+0x378/0x67c [<8032ee88>] platform_drv_probe+0x20/0x50 [<8032d48c>] driver_probe_device+0x118/0x234 [<8032d690>] __driver_attach+0x9c/0xa0 [<8032b89c>] bus_for_each_dev+0x68/0x9c [<8032cf44>] driver_attach+0x20/0x28 [<8032cbc8>] bus_add_driver+0x148/0x1f4 [<8032dce0>] driver_register+0x80/0x100 [<8032ee54>] __platform_driver_register+0x50/0x64 [<8084b094>] sdhci_esdhc_imx_driver_init+0x18/0x20 [<80008980>] do_one_initcall+0x108/0x16c [<8081cca4>] kernel_init_freeable+0x10c/0x1d0 [<80611b28>] kernel_init+0x10/0x120 [<8000e9c8>] ret_from_fork+0x14/0x2c irq event stamp: 805 hardirqs last enabled at (805): [<8061d43c>] _raw_spin_unlock_irqrestore+0x38/0x4c hardirqs last disabled at (804): [<8061d2c8>] _raw_spin_lock_irqsave+0x24/0x54 softirqs last enabled at (570): [<8002b824>] __do_softirq+0x1c4/0x290 softirqs last disabled at (561): [<8002bcf4>] irq_exit+0xb4/0x10c other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(&(&host->lock)->rlock); <Interrupt> lock(&(&host->lock)->rlock); *** DEADLOCK *** 2 locks held by kworker/u2:1/33: #0: (kmmcd){.+.+..}, at: [<8003db18>] process_one_work+0x128/0x468 #1: ((&(&host->detect)->work)){+.+...}, at: [<8003db18>] process_one_work+0x128/0x468 stack backtrace: CPU: 0 PID: 33 Comm: kworker/u2:1 Not tainted 3.13.0-rc1+ #287 Workqueue: kmmcd mmc_rescan Backtrace: [<80012160>] (dump_backtrace+0x0/0x10c) from [<80012438>] (show_stack+0x18/0x1c) r6:bfad0900 r5:00000000 r4:8088ecc8 r3:bfad0900 [<80012420>] (show_stack+0x0/0x1c) from [<806169ec>] (dump_stack+0x84/0x9c) [<80616968>] (dump_stack+0x0/0x9c) from [<806147b4>] (print_usage_bug+0x260/0x2d0) r5:8076ba88 r4:80977410 [<80614554>] (print_usage_bug+0x0/0x2d0) from [<8005f0d0>] (mark_lock+0x1e0/0x6ac) r9:8005e678 r8:00000000 r7:bfad0900 r6:00001015 r5:bfad0cd0 r4:00000002 [<8005eef0>] (mark_lock+0x0/0x6ac) from [<80060234>] (__lock_acquire+0x604/0x1cbc) [<8005fc30>] (__lock_acquire+0x0/0x1cbc) from [<800620d0>] (lock_acquire+0x70/0x84) [<80062060>] (lock_acquire+0x0/0x84) from [<8061d1c8>] (_raw_spin_lock+0x30/0x40) r7:00000000 r6:bfb63000 r5:00000000 r4:bfb60568 [<8061d198>] (_raw_spin_lock+0x0/0x40) from [<8045f7f4>] (sdhci_execute_tuning+0x4c/0x710) r4:bfb60000 [<8045f7a8>] (sdhci_execute_tuning+0x0/0x710) from [<80453454>] (mmc_sd_init_card+0x5f8/0x660) [<80452e5c>] (mmc_sd_init_card+0x0/0x660) from [<80453748>] (mmc_attach_sd+0xb4/0x180) r9:bf92d400 r8:8065f364 r7:00061a80 r6:bfb60000 r5:8065f358 r4:bfb60000 [<80453694>] (mmc_attach_sd+0x0/0x180) from [<8044d9f8>] (mmc_rescan+0x284/0x2f0) r5:8065f358 r4:bfb602f8 [<8044d774>] (mmc_rescan+0x0/0x2f0) from [<8003db94>] (process_one_work+0x1a4/0x468) r8:00000000 r7:bfb55eb0 r6:bf80dc00 r5:bfb602f8 r4:bfb35980 r3:8044d774 [<8003d9f0>] (process_one_work+0x0/0x468) from [<8003e850>] (worker_thread+0x118/0x3e0) [<8003e738>] (worker_thread+0x0/0x3e0) from [<80044de0>] (kthread+0xd4/0xf0) [<80044d0c>] (kthread+0x0/0xf0) from [<8000e9c8>] (ret_from_fork+0x14/0x2c) r7:00000000 r6:00000000 r5:80044d0c r4:bfb37b40 Signed-off-by: Dong Aisheng <b29396@freescale.com> Cc: stable <stable@vger.kernel.org> Signed-off-by: Chris Ball <chris@printf.net>

The rport timers must be stopped before the SRP initiator destroys the resources associated with the SCSI host. This is necessary because otherwise the callback functions invoked from the SRP transport layer could trigger a use-after-free. Stopping the rport timers before invoking scsi_remove_host() can trigger long delays in the SCSI error handler if a transport layer failure occurs while scsi_remove_host() is in progress. Hence move the code for stopping the rport timers from srp_rport_release() into a new function and invoke that function after scsi_remove_host() has finished. This patch fixes the following sporadic kernel crash: kernel BUG at include/asm-generic/dma-mapping-common.h:64! invalid opcode: 0000 [#1] SMP RIP: 0010:[<ffffffffa03b20b1>] [<ffffffffa03b20b1>] srp_unmap_data+0x121/0x130 [ib_srp] Call Trace: [<ffffffffa03b20fc>] srp_free_req+0x3c/0x80 [ib_srp] [<ffffffffa03b2188>] srp_finish_req+0x48/0x70 [ib_srp] [<ffffffffa03b21fb>] srp_terminate_io+0x4b/0x60 [ib_srp] [<ffffffffa03a6fb5>] __rport_fail_io_fast+0x75/0x80 [scsi_transport_srp] [<ffffffffa03a7438>] rport_fast_io_fail_timedout+0x88/0xc0 [scsi_transport_srp] [<ffffffff8108b370>] worker_thread+0x170/0x2a0 [<ffffffff81090876>] kthread+0x96/0xa0 [<ffffffff8100c0ca>] child_rip+0xa/0x20 Signed-off-by: Bart Van Assche <bvanassche@acm.org> Signed-off-by: Roland Dreier <roland@purestorage.com>

These changes correct the following issues with jumbo frames on the stmmac driver: 1) The Synopsys EMAC can be configured to support different FIFO sizes at core configuration time. There's no way to query the controller and know the FIFO size, so the driver needs to get this information from the device tree in order to know how to correctly handle MTU changes and setting up dma buffers. The default max-frame-size is as currently used, which is the size of a jumbo frame. 2) The driver was enabling Jumbo frames by default, but was not allocating dma buffers of sufficient size to handle the maximum possible packet size that could be received. This led to memory corruption since DMAs were occurring beyond the extent of the allocated receive buffers for certain types of network traffic. kernel BUG at net/core/skbuff.c:126! Internal error: Oops - BUG: 0 [#1] SMP ARM Modules linked in: CPU: 0 PID: 563 Comm: sockperf Not tainted 3.13.0-rc6-01523-gf7111b9 #31 task: ef35e580 ti: ef252000 task.ti: ef252000 PC is at skb_panic+0x60/0x64 LR is at skb_panic+0x60/0x64 pc : [<c03c7c3c>] lr : [<c03c7c3c>] psr: 60000113 sp : ef253c18 ip : 60000113 fp : 00000000 r10: ef3a5400 r9 : 00000ebc r8 : ef3a546c r7 : ee59f000 r6 : ee59f08 r5 : ee59ff40 r4 : ee59f140 r3 : 000003e2 r2 : 00000007 r1 : c0b9c420 r0 : 0000007d Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user Control: 10c5387d Table: 2e8ac04a DAC: 00000015 Process sockperf (pid: 563, stack limit = 0xef252248) Stack: (0xef253c18 to 0xef254000) 3c00: 00000ebc ee59f000 3c20: ee59f08 ee59ff40 ee59f140 c04a9cd8 ee8c50c0 00000ebc ee59ff40 00000000 3c40: ee59f140 c02d0ef0 00000056 ef1eda80 ee8c50c0 00000ebc 22bbef29 c0318f8c 3c60: 00000056 ef3a547c ffe2c716 c02c9c90 c0ba1298 ef3a5838 ef3a5838 ef3a5400 3c80: 000020c0 ee573840 000055cb ef3f2050 c053f0e0 c0319214 22b9b085 22d92813 3ca0: 00001c80 004b8e00 ef3a5400 ee573840 ef3f2064 22d92813 ef3f2064 000055cb 3cc0: ef3f2050 c031a19c ef252000 00000000 00000000 c0561bc0 00000000 ff00ffff 3ce0: c05621c0 ef3a5400 ef3f2064 ee573840 00000020 ef3f2064 000055cb ef3f2050 3d00: c053f0e0 c031cad0 c053e740 00000e60 00000000 00000000 ee573840 ef3a5400 3d20: ef0a6e00 00000000 ef3f2064 c032507c 00010000 00000020 c0561bc0 c0561bc0 3d40: ee599850 c032799c 00000000 ee573840 c055a380 ef3a5400 00000000 ef3f2064 3d60: ef3f2050 c032799c 0101c7c0 2b6755cb c059a280 c030e4d8 000055cb ffffffff 3d80: ee574fc0 c055a380 ee574000 ee573840 00002b67 ee573840 c03fe9c4 c053fa68 3da0: c055a380 00001f6f 00000000 ee573840 c053f0e0 c0304fd ef0a6e01 ef3f2050 3dc0: ee573858 ef031000 ee573840 c03055d8 c0ba0c40 ef000f40 00100100 c053f0dc 3de0: c053ffdc c053f0f0 00000008 00000000 ef031000 c02da948 00001140 00000000 3e00: c0563c78 ef253e5f 00000020 ee573840 00000020 c053f0f0 ef313400 ee573840 3e20: c053f0e0 00000000 00000000 c05380c0 ef313400 00001000 00000015 c02df280 3e40: ee574000 ef001e00 00000000 00001080 00000042 005cd980 ef031500 ef031500 3e60: 00000000 c02df824 ef031500 c053e390 c0541084 f00b1e00 c05925e8 c02df864 3e80: 00001f5c ef031440 c053e390 c0278524 00000002 00000000 c0b9eb48 c02df280 3ea0: ee8c7180 00000100 c0542ca8 00000015 00000040 ef031500 ef031500 ef031500 3ec0: c027803c ef252000 00000040 000000ec c05380c0 c0b9eb40 c0b9eb48 c02df940 3ee0: ef060780 ffffa4dd c0564a9c c056343c 002e80a8 00000080 ef031500 00000001 3f00: c053808c ef252000 fffec100 00000003 00000004 002e80a8 0000000c c00258f0 3f20: 002e80a8 c005e704 00000005 00000100 c05634d0 c0538080 c05333e0 00000000 3f40: 0000000a c0565580 c05380c0 ffffa4dc c05434f4 00400100 00000004 c0534cd4 3f60: 00000098 00000000 fffec100 002e80a8 00000004 002e80a8 002a20e0 c0025da8 3f80: c0534cd4 c000f020 fffec10c c053ea60 ef253fb0 c0008530 0000ffe2 b6ef67f4 3fa0: 40000010 ffffffff 00000124 c0012f3c 0000ffe2 002e80f0 0000ffe2 00004000 3fc0: becb6338 becb6334 00000004 00000124 002e80a8 00000004 002e80a8 002a20e0 3fe0: becb630 becb62f4 002773bb b6ef67f4 40000010 ffffffff 00000000 00000000 [<c03c7c3c>] (skb_panic+0x60/0x64) from [<c02d0ef0>] (skb_put+0x4c/0x50) [<c02d0ef0>] (skb_put+0x4c/0x50) from [<c0318f8c>] (tcp_collapse+0x314/0x3ec) [<c0318f8c>] (tcp_collapse+0x314/0x3ec) from [<c0319214>] (tcp_try_rmem_schedule+0x1b0/0x3c4) [<c0319214>] (tcp_try_rmem_schedule+0x1b0/0x3c4) from [<c031a19c>] (tcp_data_queue+0x480/0xe6c) [<c031a19c>] (tcp_data_queue+0x480/0xe6c) from [<c031cad0>] (tcp_rcv_established+0x180/0x62c) [<c031cad0>] (tcp_rcv_established+0x180/0x62c) from [<c032507c>] (tcp_v4_do_rcv+0x13c/0x31c) [<c032507c>] (tcp_v4_do_rcv+0x13c/0x31c) from [<c032799c>] (tcp_v4_rcv+0x718/0x73c) [<c032799c>] (tcp_v4_rcv+0x718/0x73c) from [<c0304fdc>] (ip_local_deliver+0x98/0x274) [<c0304fdc>] (ip_local_deliver+0x98/0x274) from [<c03055d8>] (ip_rcv+0x420/0x758) [<c03055d8>] (ip_rcv+0x420/0x758) from [<c02da948>] (__netif_receive_skb_core+0x44c/0x5bc) [<c02da948>] (__netif_receive_skb_core+0x44c/0x5bc) from [<c02df280>] (netif_receive_skb+0x48/0xb4) [<c02df280>] (netif_receive_skb+0x48/0xb4) from [<c02df824>] (napi_gro_flush+0x70/0x94) [<c02df824>] (napi_gro_flush+0x70/0x94) from [<c02df864>] (napi_complete+0x1c/0x34) [<c02df864>] (napi_complete+0x1c/0x34) from [<c0278524>] (stmmac_poll+0x4e8/0x5c8) [<c0278524>] (stmmac_poll+0x4e8/0x5c8) from [<c02df940>] (net_rx_action+0xc4/0x1e4) [<c02df940>] (net_rx_action+0xc4/0x1e4) from [<c00258f0>] (__do_softirq+0x12c/0x2e8) [<c00258f0>] (__do_softirq+0x12c/0x2e8) from [<c0025da8>] (irq_exit+0x78/0xac) [<c0025da8>] (irq_exit+0x78/0xac) from [<c000f020>] (handle_IRQ+0x44/0x90) [<c000f020>] (handle_IRQ+0x44/0x90) from [<c0008530>] (gic_handle_irq+0x2c/0x5c) [<c0008530>] (gic_handle_irq+0x2c/0x5c) from [<c0012f3c>] (__irq_usr+0x3c/0x60) 3) The driver was setting the dma buffer size after allocating dma buffers, which caused a system panic when changing the MTU. BUG: Bad page state in process ifconfig pfn:2e850 page:c0b72a00 count:0 mapcount:0 mapping: (null) index:0x0 page flags: 0x200(arch_1) Modules linked in: CPU: 0 PID: 566 Comm: ifconfig Not tainted 3.13.0-rc6-01523-gf7111b9 #29 [<c001547c>] (unwind_backtrace+0x0/0xf8) from [<c00122dc>] (show_stack+0x10/0x14) [<c00122dc>] (show_stack+0x10/0x14) from [<c03c793c>] (dump_stack+0x70/0x88) [<c03c793c>] (dump_stack+0x70/0x88) from [<c00b2620>] (bad_page+0xc8/0x118) [<c00b2620>] (bad_page+0xc8/0x118) from [<c00b302c>] (get_page_from_freelist+0x744/0x870) [<c00b302c>] (get_page_from_freelist+0x744/0x870) from [<c00b40f4>] (__alloc_pages_nodemask+0x118/0x86c) [<c00b40f4>] (__alloc_pages_nodemask+0x118/0x86c) from [<c00b4858>] (__get_free_pages+0x10/0x54) [<c00b4858>] (__get_free_pages+0x10/0x54) from [<c00cba1c>] (kmalloc_order_trace+0x24/0xa0) [<c00cba1c>] (kmalloc_order_trace+0x24/0xa0) from [<c02d199c>] (__kmalloc_reserve.isra.21+0x24/0x70) [<c02d199c>] (__kmalloc_reserve.isra.21+0x24/0x70) from [<c02d240c>] (__alloc_skb+0x68/0x13c) [<c02d240c>] (__alloc_skb+0x68/0x13c) from [<c02d3930>] (__netdev_alloc_skb+0x3c/0xe8) [<c02d3930>] (__netdev_alloc_skb+0x3c/0xe8) from [<c0279378>] (stmmac_open+0x63c/0x1024) [<c0279378>] (stmmac_open+0x63c/0x1024) from [<c02e18cc>] (__dev_open+0xa0/0xfc) [<c02e18cc>] (__dev_open+0xa0/0xfc) from [<c02e1b40>] (__dev_change_flags+0x94/0x158) [<c02e1b40>] (__dev_change_flags+0x94/0x158) from [<c02e1c24>] (dev_change_flags+0x18/0x48) [<c02e1c24>] (dev_change_flags+0x18/0x48) from [<c0337bc0>] (devinet_ioctl+0x638/0x700) [<c0337bc0>] (devinet_ioctl+0x638/0x700) from [<c02c7aec>] (sock_ioctl+0x64/0x290) [<c02c7aec>] (sock_ioctl+0x64/0x290) from [<c0100890>] (do_vfs_ioctl+0x78/0x5b8) [<c0100890>] (do_vfs_ioctl+0x78/0x5b8) from [<c0100e0c>] (SyS_ioctl+0x3c/0x5c) [<c0100e0c>] (SyS_ioctl+0x3c/0x5c) from [<c000e760>] The fixes have been verified using reproducible, automated testing. Signed-off-by: Vince Bridgers <vbridgers2013@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>

If we have EEH error happens to the adapter and we have to remove it from the system for some reasons (e.g. more than 5 EEH errors detected from the device in last hour), the adapter will be disabled for towice separately by eeh_err_detected() and remove_one(), which will incur following unexpected backtrace. The patch tries to avoid it. WARNING: at drivers/pci/pci.c:1431 CPU: 12 PID: 121 Comm: eehd Not tainted 3.13.0-rc7+ #1 task: c0000001823a3780 ti: c00000018240c000 task.ti: c00000018240c000 NIP: c0000000003c1e40 LR: c0000000003c1e3c CTR: 0000000001764c5c REGS: c00000018240f470 TRAP: 0700 Not tainted (3.13.0-rc7+) MSR: 8000000000029032 <SF,EE,ME,IR,DR,RI> CR: 28000024 XER: 00000004 CFAR: c000000000706528 SOFTE: 1 GPR00: c0000000003c1e3c c00000018240f6f0 c0000000010fe1f8 0000000000000035 GPR04: 0000000000000000 0000000000000000 00000000003ae509 0000000000000000 GPR08: 000000000000346f 0000000000000000 0000000000000000 0000000000003fef GPR12: 0000000028000022 c00000000ec93000 c0000000000c11b0 c000000184ac3e40 GPR16: 0000000000000000 0000000000000000 0000000000000000 0000000000000000 GPR20: 0000000000000000 0000000000000000 0000000000000000 0000000000000000 GPR24: 0000000000000000 c0000000009398d8 c00000000101f9c0 c0000001860ae000 GPR28: c000000182ba0000 00000000000001f0 c0000001860ae6f8 c0000001860ae000 NIP [c0000000003c1e40] .pci_disable_device+0xd0/0xf0 LR [c0000000003c1e3c] .pci_disable_device+0xcc/0xf0 Call Trace: [c0000000003c1e3c] .pci_disable_device+0xcc/0xf0 (unreliable) [d0000000073881c4] .remove_one+0x174/0x320 [cxgb4] [c0000000003c57e0] .pci_device_remove+0x60/0x100 [c00000000046396c] .__device_release_driver+0x9c/0x120 [c000000000463a20] .device_release_driver+0x30/0x60 [c0000000003bcdb4] .pci_stop_bus_device+0x94/0xd0 [c0000000003bcf48] .pci_stop_and_remove_bus_device+0x18/0x30 [c00000000003f548] .pcibios_remove_pci_devices+0xa8/0x140 [c000000000035c00] .eeh_handle_normal_event+0xa0/0x3c0 [c000000000035f50] .eeh_handle_event+0x30/0x2b0 [c0000000000362c4] .eeh_event_handler+0xf4/0x1b0 [c0000000000c12b8] .kthread+0x108/0x130 [c00000000000a168] .ret_from_kernel_thread+0x5c/0x74 Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>

…r thp split After thp split in hwpoison_user_mappings(), we hold page lock on the raw error page only between try_to_unmap, hence we are in danger of race condition. I found in the RHEL7 MCE-relay testing that we have "bad page" error when a memory error happens on a thp tail page used by qemu-kvm: Triggering MCE exception on CPU 10 mce: [Hardware Error]: Machine check events logged MCE exception done on CPU 10 MCE 0x38c535: Killing qemu-kvm:8418 due to hardware memory corruption MCE 0x38c535: dirty LRU page recovery: Recovered qemu-kvm[8418]: segfault at 20 ip 00007ffb0f0f229a sp 00007fffd6bc5240 error 4 in qemu-kvm[7ffb0ef14000+420000] BUG: Bad page state in process qemu-kvm pfn:38c400 page:ffffea000e310000 count:0 mapcount:0 mapping: (null) index:0x7ffae3c00 page flags: 0x2fffff0008001d(locked|referenced|uptodate|dirty|swapbacked) Modules linked in: hwpoison_inject mce_inject vhost_net macvtap macvlan ... CPU: 0 PID: 8418 Comm: qemu-kvm Tainted: G M -------------- 3.10.0-54.0.1.el7.mce_test_fixed.x86_64 #1 Hardware name: NEC NEC Express5800/R120b-1 [N8100-1719F]/MS-91E7-001, BIOS 4.6.3C19 02/10/2011 Call Trace: dump_stack+0x19/0x1b bad_page.part.59+0xcf/0xe8 free_pages_prepare+0x148/0x160 free_hot_cold_page+0x31/0x140 free_hot_cold_page_list+0x46/0xa0 release_pages+0x1c1/0x200 free_pages_and_swap_cache+0xad/0xd0 tlb_flush_mmu.part.46+0x4c/0x90 tlb_finish_mmu+0x55/0x60 exit_mmap+0xcb/0x170 mmput+0x67/0xf0 vhost_dev_cleanup+0x231/0x260 [vhost_net] vhost_net_release+0x3f/0x90 [vhost_net] __fput+0xe9/0x270 ____fput+0xe/0x10 task_work_run+0xc4/0xe0 do_exit+0x2bb/0xa40 do_group_exit+0x3f/0xa0 get_signal_to_deliver+0x1d0/0x6e0 do_signal+0x48/0x5e0 do_notify_resume+0x71/0xc0 retint_signal+0x48/0x8c The reason of this bug is that a page fault happens before unlocking the head page at the end of memory_failure(). This strange page fault is trying to access to address 0x20 and I'm not sure why qemu-kvm does this, but anyway as a result the SIGSEGV makes qemu-kvm exit and on the way we catch the bad page bug/warning because we try to free a locked page (which was the former head page.) To fix this, this patch suggests to shift page lock from head page to tail page just after thp split. SIGSEGV still happens, but it affects only error affected VMs, not a whole system. Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Cc: Andi Kleen <andi@firstfloor.org> Cc: Wanpeng Li <liwanp@linux.vnet.ibm.com> Cc: <stable@vger.kernel.org> [3.9+] # a3e0f9e "mm/memory-failure.c: transfer page count from head page to tail page after split thp" Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

This warning was reported recently: WARNING: at drivers/scsi/libfc/fc_exch.c:478 fc_seq_send+0x14f/0x160 [libfc]() (Not tainted) Hardware name: ProLiant DL120 G7 Modules linked in: tcm_fc target_core_iblock target_core_file target_core_pscsi target_core_mod configfs dm_round_robin dm_multipath 8021q garp stp llc bnx2fc cnic uio fcoe libfcoe libfc scsi_transport_fc scsi_tgt autofs4 sunrpc pcc_cpufreq ipv6 hpilo hpwdt e1000e microcode iTCO_wdt iTCO_vendor_support serio_raw shpchp ixgbe dca mdio sg ext4 mbcache jbd2 sd_mod crc_t10dif pata_acpi ata_generic ata_piix hpsa dm_mirror dm_region_hash dm_log dm_mod [last unloaded: scsi_wait_scan] Pid: 5464, comm: target_completi Not tainted 2.6.32-272.el6.x86_64 #1 Call Trace: [<ffffffff8106b747>] ? warn_slowpath_common+0x87/0xc0 [<ffffffff8106b79a>] ? warn_slowpath_null+0x1a/0x20 [<ffffffffa025f7df>] ? fc_seq_send+0x14f/0x160 [libfc] [<ffffffffa035cbce>] ? ft_queue_status+0x16e/0x210 [tcm_fc] [<ffffffffa030a660>] ? target_complete_ok_work+0x0/0x4b0 [target_core_mod] [<ffffffffa030a766>] ? target_complete_ok_work+0x106/0x4b0 [target_core_mod] [<ffffffffa030a660>] ? target_complete_ok_work+0x0/0x4b0 [target_core_mod] [<ffffffff8108c760>] ? worker_thread+0x170/0x2a0 [<ffffffff810920d0>] ? autoremove_wake_function+0x0/0x40 [<ffffffff8108c5f0>] ? worker_thread+0x0/0x2a0 [<ffffffff81091d66>] ? kthread+0x96/0xa0 [<ffffffff8100c14a>] ? child_rip+0xa/0x20 [<ffffffff81091cd0>] ? kthread+0x0/0xa0 [<ffffffff8100c140>] ? child_rip+0x0/0x20 It occurs because fc_seq_send can have multiple contexts executing within it at the same time, and fc_seq_send doesn't consistently use the ep->ex_lock that protects this structure. Because of that, its possible for one context to clear the INIT bit in the ep->esb_state field while another checks it, leading to the above stack trace generated by the WARN_ON in the function. We should probably undertake the effort to convert access to the fc_exch structures to use rcu, but that a larger work item. To just fix this specific issue, we can just extend the ex_lock protection through the entire fc_seq_send path Signed-off-by: Neil Horman <nhorman@tuxdriver.com> Reported-by: Gris Ge <fge@redhat.com> CC: Robert Love <robert.w.love@intel.com> Signed-off-by: Robert Love <robert.w.love@intel.com>

A long time ago in a galaxy far away.... .. the was a commit made to fix some ilinux specific "fragmented buffer" log recovery problem: http://oss.sgi.com/cgi-bin/gitweb.cgi?p=archive/xfs-import.git;a=commitdiff;h=b29c0bece51da72fb3ff3b61391a391ea54e1603 That problem occurred when a contiguous dirty region of a buffer was split across across two pages of an unmapped buffer. It's been a long time since that has been done in XFS, and the changes to log the entire inode buffers for CRC enabled filesystems has re-introduced that corner case. And, of course, it turns out that the above commit didn't actually fix anything - it just ensured that log recovery is guaranteed to fail when this situation occurs. And now for the gory details. xfstest xfs/085 is failing with this assert: XFS (vdb): bad number of regions (0) in inode log format XFS: Assertion failed: 0, file: fs/xfs/xfs_log_recover.c, line: 1583 Largely undocumented factoid #1: Log recovery depends on all log buffer format items starting with this format: struct foo_log_format { __uint16_t type; __uint16_t size; .... As recoery uses the size field and assumptions about 32 bit alignment in decoding format items. So don't pay much attention to the fact log recovery thinks that it decoding an inode log format item - it just uses them to determine what the size of the item is. But why would it see a log format item with a zero size? Well, luckily enough xfs_logprint uses the same code and gives the same error, so with a bit of gdb magic, it turns out that it isn't a log format that is being decoded. What logprint tells us is this: Oper (130): tid: a0375e1a len: 28 clientid: TRANS flags: none BUF: #regs: 2 start blkno: 144 (0x90) len: 16 bmap size: 2 flags: 0x4000 Oper (131): tid: a0375e1a len: 4096 clientid: TRANS flags: none BUF DATA ---------------------------------------------------------------------------- Oper (132): tid: a0375e1a len: 4096 clientid: TRANS flags: none xfs_logprint: unknown log operation type (4e49) ********************************************************************** * ERROR: data block=2 * ********************************************************************** That we've got a buffer format item (oper 130) that has two regions; the format item itself and one dirty region. The subsequent region after the buffer format item and it's data is them what we are tripping over, and the first bytes of it at an inode magic number. Not a log opheader like there is supposed to be. That means there's a problem with the buffer format item. It's dirty data region is 4096 bytes, and it contains - you guessed it - initialised inodes. But inode buffers are 8k, not 4k, and we log them in their entirety. So something is wrong here. The buffer format item contains: (gdb) p /x *(struct xfs_buf_log_format *)in_f $22 = {blf_type = 0x123c, blf_size = 0x2, blf_flags = 0x4000, blf_len = 0x10, blf_blkno = 0x90, blf_map_size = 0x2, blf_data_map = {0xffffffff, 0xffffffff, .... }} Two regions, and a signle dirty contiguous region of 64 bits. 64 * 128 = 8k, so this should be followed by a single 8k region of data. And the blf_flags tell us that the type of buffer is a XFS_BLFT_DINO_BUF. It contains inodes. And because it doesn't have the XFS_BLF_INODE_BUF flag set, that means it's an inode allocation buffer. So, it should be followed by 8k of inode data. But we know that the next region has a header of: (gdb) p /x *ohead $25 = {oh_tid = 0x1a5e37a0, oh_len = 0x100000, oh_clientid = 0x69, oh_flags = 0x0, oh_res2 = 0x0} and so be32_to_cpu(oh_len) = 0x1000 = 4096 bytes. It's simply not long enough to hold all the logged data. There must be another region. There is - there's a following opheader for another 4k of data that contains the other half of the inode cluster data - the one we assert fail on because it's not a log format header. So why is the second part of the data not being accounted to the correct buffer log format structure? It took a little more work with gdb to work out that the buffer log format structure was both expecting it to be there but hadn't accounted for it. It was at that point I went to the kernel code, as clearly this wasn't a bug in xfs_logprint and the kernel was writing bad stuff to the log. First port of call was the buffer item formatting code, and the discontiguous memory/contiguous dirty region handling code immediately stood out. I've wondered for a long time why the code had this comment in it: vecp->i_addr = xfs_buf_offset(bp, buffer_offset); vecp->i_len = nbits * XFS_BLF_CHUNK; vecp->i_type = XLOG_REG_TYPE_BCHUNK; /* * You would think we need to bump the nvecs here too, but we do not * this number is used by recovery, and it gets confused by the boundary * split here * nvecs++; */ vecp++; And it didn't account for the extra vector pointer. The case being handled here is that a contiguous dirty region lies across a boundary that cannot be memcpy()d across, and so has to be split into two separate operations for xlog_write() to perform. What this code assumes is that what is written to the log is two consecutive blocks of data that are accounted in the buf log format item as the same contiguous dirty region and so will get decoded as such by the log recovery code. The thing is, xlog_write() knows nothing about this, and so just does it's normal thing of adding an opheader for each vector. That means the 8k region gets written to the log as two separate regions of 4k each, but because nvecs has not been incremented, the buf log format item accounts for only one of them. Hence when we come to log recovery, we process the first 4k region and then expect to come across a new item that starts with a log format structure of some kind that tells us whenteh next data is going to be. Instead, we hit raw buffer data and things go bad real quick. So, the commit from 2002 that commented out nvecs++ is just plain wrong. It breaks log recovery completely, and it would seem the only reason this hasn't been since then is that we don't log large contigous regions of multi-page unmapped buffers very often. Never would be a closer estimate, at least until the CRC code came along.... So, lets fix that by restoring the nvecs accounting for the extra region when we hit this case..... .... and there's the problemin log recovery it is apparently working around: XFS: Assertion failed: i == item->ri_total, file: fs/xfs/xfs_log_recover.c, line: 2135 Yup, xlog_recover_do_reg_buffer() doesn't handle contigous dirty regions being broken up into multiple regions by the log formatting code. That's an easy fix, though - if the number of contiguous dirty bits exceeds the length of the region being copied out of the log, only account for the number of dirty bits that region covers, and then loop again and copy more from the next region. It's a 2 line fix. Now xfstests xfs/085 passes, we have one less piece of mystery code, and one more important piece of knowledge about how to structure new log format items.. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Mark Tinguely <tinguely@sgi.com> Signed-off-by: Ben Myers <bpm@sgi.com>

Got bellow lockdep warning during tests. It is false alarm though. [ 1184.479097] ============================================= [ 1184.479187] [ INFO: possible recursive locking detected ] [ 1184.479277] 3.10.0-rc3+ #13 Tainted: G C [ 1184.479355] --------------------------------------------- [ 1184.479444] mkdir/2215 is trying to acquire lock: [ 1184.479521] (&(&dentry->d_lock)->rlock){+.+...}, at: [<ffffffffa06cc27c>] ll_md_blocking_ast+0x55c/0x655 [lustre] [ 1184.479801] but task is already holding lock: [ 1184.479895] (&(&dentry->d_lock)->rlock){+.+...}, at: [<ffffffffa06cc1b1>] ll_md_blocking_ast+0x491/0x655 [lustre] [ 1184.480101] other info that might help us debug this: [ 1184.480206] Possible unsafe locking scenario: [ 1184.480300] CPU0 [ 1184.480340] ---- [ 1184.480380] lock(&(&dentry->d_lock)->rlock); [ 1184.480458] lock(&(&dentry->d_lock)->rlock); [ 1184.480536] *** DEADLOCK *** [ 1184.480761] May be due to missing lock nesting notation [ 1184.480936] 4 locks held by mkdir/2215: [ 1184.481037] #0: (sb_writers#11){.+.+.+}, at: [<ffffffff811531a9>] mnt_want_write+0x24/0x4b [ 1184.481273] #1: (&type->i_mutex_dir_key#3/1){+.+.+.}, at: [<ffffffff81144fce>] kern_path_create+0x8c/0x144 [ 1184.481513] #2: (&sb->s_type->i_lock_key#19){+.+...}, at: [<ffffffffa06cc180>] ll_md_blocking_ast+0x460/0x655 [lustre] [ 1184.481778] #3: (&(&dentry->d_lock)->rlock){+.+...}, at: [<ffffffffa06cc1b1>] ll_md_blocking_ast+0x491/0x655 [lustre] [ 1184.482050] Signed-off-by: Peng Tao <tao.peng@emc.com> Signed-off-by: Andreas Dilger <andreas.dilger@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

There is a potential deadlock that can happen in try_release_subpage_extent_buffer() because the irq-safe xarray spin lock fs_info->buffer_tree is being acquired before the irq-unsafe eb->refs_lock. This leads to the potential race: // T1 (random eb->refs user) // T2 (release folio) spin_lock(&eb->refs_lock); // interrupt end_bbio_meta_write() btrfs_meta_folio_clear_writeback() btree_release_folio() folio_test_writeback() //false try_release_extent_buffer() try_release_subpage_extent_buffer() xa_lock_irq(&fs_info->buffer_tree) spin_lock(&eb->refs_lock); // blocked; held by T1 buffer_tree_clear_mark() xas_lock_irqsave() // blocked; held by T2 I believe that the spin lock can safely be replaced by an rcu_read_lock. The xa_for_each loop does not need the spin lock as it's already internally protected by the rcu_read_lock. The extent buffer is also protected by the rcu_read_lock so it won't be freed before we take the eb->refs_lock and check the ref count. The rcu_read_lock is taken and released every iteration, just like the spin lock, which means we're not protected against concurrent insertions into the xarray. This is fine because we rely on folio->private to detect if there are any ebs remaining in the folio. There is already some precedent for this with find_extent_buffer_nolock, which loads an extent buffer from the xarray with only rcu_read_lock. lockdep warning: ===================================================== WARNING: HARDIRQ-safe -> HARDIRQ-unsafe lock order detected 6.16.0-0_fbk701_debug_rc0_123_g4c06e63b9203 #1 Tainted: G E N ----------------------------------------------------- kswapd0/66 [HC0[0]:SC0[0]:HE0:SE1] is trying to acquire: ffff000011ffd600 (&eb->refs_lock){+.+.}-{3:3}, at: try_release_extent_buffer+0x18c/0x560 and this task is already holding: ffff0000c1d91b88 (&buffer_xa_class){-.-.}-{3:3}, at: try_release_extent_buffer+0x13c/0x560 which would create a new lock dependency: (&buffer_xa_class){-.-.}-{3:3} -> (&eb->refs_lock){+.+.}-{3:3} but this new dependency connects a HARDIRQ-irq-safe lock: (&buffer_xa_class){-.-.}-{3:3} ... which became HARDIRQ-irq-safe at: lock_acquire+0x178/0x358 _raw_spin_lock_irqsave+0x60/0x88 buffer_tree_clear_mark+0xc4/0x160 end_bbio_meta_write+0x238/0x398 btrfs_bio_end_io+0x1f8/0x330 btrfs_orig_write_end_io+0x1c4/0x2c0 bio_endio+0x63c/0x678 blk_update_request+0x1c4/0xa00 blk_mq_end_request+0x54/0x88 virtblk_request_done+0x124/0x1d0 blk_mq_complete_request+0x84/0xa0 virtblk_done+0x130/0x238 vring_interrupt+0x130/0x288 __handle_irq_event_percpu+0x1e8/0x708 handle_irq_event+0x98/0x1b0 handle_fasteoi_irq+0x264/0x7c0 generic_handle_domain_irq+0xa4/0x108 gic_handle_irq+0x7c/0x1a0 do_interrupt_handler+0xe4/0x148 el1_interrupt+0x30/0x50 el1h_64_irq_handler+0x14/0x20 el1h_64_irq+0x6c/0x70 _raw_spin_unlock_irq+0x38/0x70 __run_timer_base+0xdc/0x5e0 run_timer_softirq+0xa0/0x138 handle_softirqs.llvm.13542289750107964195+0x32c/0xbd0 ____do_softirq.llvm.17674514681856217165+0x18/0x28 call_on_irq_stack+0x24/0x30 __irq_exit_rcu+0x164/0x430 irq_exit_rcu+0x18/0x88 el1_interrupt+0x34/0x50 el1h_64_irq_handler+0x14/0x20 el1h_64_irq+0x6c/0x70 arch_local_irq_enable+0x4/0x8 do_idle+0x1a0/0x3b8 cpu_startup_entry+0x60/0x80 rest_init+0x204/0x228 start_kernel+0x394/0x3f0 __primary_switched+0x8c/0x8958 to a HARDIRQ-irq-unsafe lock: (&eb->refs_lock){+.+.}-{3:3} ... which became HARDIRQ-irq-unsafe at: ... lock_acquire+0x178/0x358 _raw_spin_lock+0x4c/0x68 free_extent_buffer_stale+0x2c/0x170 btrfs_read_sys_array+0x1b0/0x338 open_ctree+0xeb0/0x1df8 btrfs_get_tree+0xb60/0x1110 vfs_get_tree+0x8c/0x250 fc_mount+0x20/0x98 btrfs_get_tree+0x4a4/0x1110 vfs_get_tree+0x8c/0x250 do_new_mount+0x1e0/0x6c0 path_mount+0x4ec/0xa58 __arm64_sys_mount+0x370/0x490 invoke_syscall+0x6c/0x208 el0_svc_common+0x14c/0x1b8 do_el0_svc+0x4c/0x60 el0_svc+0x4c/0x160 el0t_64_sync_handler+0x70/0x100 el0t_64_sync+0x168/0x170 other info that might help us debug this: Possible interrupt unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&eb->refs_lock); local_irq_disable(); lock(&buffer_xa_class); lock(&eb->refs_lock); <Interrupt> lock(&buffer_xa_class); *** DEADLOCK *** 2 locks held by kswapd0/66: #0: ffff800085506e40 (fs_reclaim){+.+.}-{0:0}, at: balance_pgdat+0xe8/0xe50 #1: ffff0000c1d91b88 (&buffer_xa_class){-.-.}-{3:3}, at: try_release_extent_buffer+0x13c/0x560 Link: https://www.kernel.org/doc/Documentation/locking/lockdep-design.rst#:~:text=Multi%2Dlock%20dependency%20rules%3A Fixes: 19d7f65 ("btrfs: convert the buffer_radix to an xarray") CC: stable@vger.kernel.org # 6.16+ Reviewed-by: Boris Burkov <boris@bur.io> Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: Leo Martins <loemra.dev@gmail.com> Signed-off-by: David Sterba <dsterba@suse.com>

The existing code move the VF NIC to new namespace when NETDEV_REGISTER is received on netvsc NIC. During deletion of the namespace, default_device_exit_batch() >> default_device_exit_net() is called. When netvsc NIC is moved back and registered to the default namespace, it automatically brings VF NIC back to the default namespace. This will cause the default_device_exit_net() >> for_each_netdev_safe loop unable to detect the list end, and hit NULL ptr: [ 231.449420] mana 7870:00:00.0 enP30832s1: Moved VF to namespace with: eth0 [ 231.449656] BUG: kernel NULL pointer dereference, address: 0000000000000010 [ 231.450246] #PF: supervisor read access in kernel mode [ 231.450579] #PF: error_code(0x0000) - not-present page [ 231.450916] PGD 17b8a8067 P4D 0 [ 231.451163] Oops: Oops: 0000 [#1] SMP NOPTI [ 231.451450] CPU: 82 UID: 0 PID: 1394 Comm: kworker/u768:1 Not tainted 6.16.0-rc4+ #3 VOLUNTARY [ 231.452042] Hardware name: Microsoft Corporation Virtual Machine/Virtual Machine, BIOS Hyper-V UEFI Release v4.1 11/21/2024 [ 231.452692] Workqueue: netns cleanup_net [ 231.452947] RIP: 0010:default_device_exit_batch+0x16c/0x3f0 [ 231.453326] Code: c0 0c f5 b3 e8 d5 db fe ff 48 85 c0 74 15 48 c7 c2 f8 fd ca b2 be 10 00 00 00 48 8d 7d c0 e8 7b 77 25 00 49 8b 86 28 01 00 00 <48> 8b 50 10 4c 8b 2a 4c 8d 62 f0 49 83 ed 10 4c 39 e0 0f 84 d6 00 [ 231.454294] RSP: 0018:ff75fc7c9bf9fd00 EFLAGS: 00010246 [ 231.454610] RAX: 0000000000000000 RBX: 0000000000000002 RCX: 61c8864680b583eb [ 231.455094] RDX: ff1fa9f71462d800 RSI: ff75fc7c9bf9fd38 RDI: 0000000030766564 [ 231.455686] RBP: ff75fc7c9bf9fd78 R08: 0000000000000000 R09: 0000000000000000 [ 231.456126] R10: 0000000000000001 R11: 0000000000000004 R12: ff1fa9f70088e340 [ 231.456621] R13: ff1fa9f70088e340 R14: ffffffffb3f50c20 R15: ff1fa9f7103e6340 [ 231.457161] FS: 0000000000000000(0000) GS:ff1faa6783a08000(0000) knlGS:0000000000000000 [ 231.457707] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 231.458031] CR2: 0000000000000010 CR3: 0000000179ab2006 CR4: 0000000000b73ef0 [ 231.458434] Call Trace: [ 231.458600] <TASK> [ 231.458777] ops_undo_list+0x100/0x220 [ 231.459015] cleanup_net+0x1b8/0x300 [ 231.459285] process_one_work+0x184/0x340 To fix it, move the ns change to a workqueue, and take rtnl_lock to avoid changing the netdev list when default_device_exit_net() is using it. Cc: stable@vger.kernel.org Fixes: 4c26280 ("hv_netvsc: Fix VF namespace also in synthetic NIC NETDEV_REGISTER event") Signed-off-by: Haiyang Zhang <haiyangz@microsoft.com> Link: https://patch.msgid.link/1754511711-11188-1-git-send-email-haiyangz@linux.microsoft.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Since EROFS handles decompression in non-atomic contexts due to uncontrollable decompression latencies and vmap() usage, it tries to detect atomic contexts and only kicks off a kworker on demand in order to reduce unnecessary scheduling overhead. However, the current approach is insufficient and can lead to sleeping function calls in invalid contexts, causing kernel warnings and potential system instability. See the stacktrace [1] and previous discussion [2]. The current implementation only checks rcu_read_lock_any_held(), which behaves inconsistently across different kernel configurations: - When CONFIG_DEBUG_LOCK_ALLOC is enabled: correctly detects RCU critical sections by checking rcu_lock_map - When CONFIG_DEBUG_LOCK_ALLOC is disabled: compiles to "!preemptible()", which only checks preempt_count and misses RCU critical sections This patch introduces z_erofs_in_atomic() to provide comprehensive atomic context detection: 1. Check RCU preemption depth when CONFIG_PREEMPTION is enabled, as RCU critical sections may not affect preempt_count but still require atomic handling 2. Always use async processing when CONFIG_PREEMPT_COUNT is disabled, as preemption state cannot be reliably determined 3. Fall back to standard preemptible() check for remaining cases The function replaces the previous complex condition check and ensures that z_erofs always uses (kthread_)work in atomic contexts to minimize scheduling overhead and prevent sleeping in invalid contexts. [1] Problem stacktrace [ 61.266692] BUG: sleeping function called from invalid context at kernel/locking/rtmutex_api.c:510 [ 61.266702] in_atomic(): 0, irqs_disabled(): 0, non_block: 0, pid: 107, name: irq/54-ufshcd [ 61.266704] preempt_count: 0, expected: 0 [ 61.266705] RCU nest depth: 2, expected: 0 [ 61.266710] CPU: 0 UID: 0 PID: 107 Comm: irq/54-ufshcd Tainted: G W O 6.12.17 #1 [ 61.266714] Tainted: [W]=WARN, [O]=OOT_MODULE [ 61.266715] Hardware name: schumacher (DT) [ 61.266717] Call trace: [ 61.266718] dump_backtrace+0x9c/0x100 [ 61.266727] show_stack+0x20/0x38 [ 61.266728] dump_stack_lvl+0x78/0x90 [ 61.266734] dump_stack+0x18/0x28 [ 61.266736] __might_resched+0x11c/0x180 [ 61.266743] __might_sleep+0x64/0xc8 [ 61.266745] mutex_lock+0x2c/0xc0 [ 61.266748] z_erofs_decompress_queue+0xe8/0x978 [ 61.266753] z_erofs_decompress_kickoff+0xa8/0x190 [ 61.266756] z_erofs_endio+0x168/0x288 [ 61.266758] bio_endio+0x160/0x218 [ 61.266762] blk_update_request+0x244/0x458 [ 61.266766] scsi_end_request+0x38/0x278 [ 61.266770] scsi_io_completion+0x4c/0x600 [ 61.266772] scsi_finish_command+0xc8/0xe8 [ 61.266775] scsi_complete+0x88/0x148 [ 61.266777] blk_mq_complete_request+0x3c/0x58 [ 61.266780] scsi_done_internal+0xcc/0x158 [ 61.266782] scsi_done+0x1c/0x30 [ 61.266783] ufshcd_compl_one_cqe+0x12c/0x438 [ 61.266786] __ufshcd_transfer_req_compl+0x2c/0x78 [ 61.266788] ufshcd_poll+0xf4/0x210 [ 61.266789] ufshcd_transfer_req_compl+0x50/0x88 [ 61.266791] ufshcd_intr+0x21c/0x7c8 [ 61.266792] irq_forced_thread_fn+0x44/0xd8 [ 61.266796] irq_thread+0x1a4/0x358 [ 61.266799] kthread+0x12c/0x138 [ 61.266802] ret_from_fork+0x10/0x20 [2] https://lore.kernel.org/r/58b661d0-0ebb-4b45-a10d-c5927fb791cd@paulmck-laptop Signed-off-by: Junli Liu <liujunli@lixiang.com> Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com> Link: https://lore.kernel.org/r/20250805011957.911186-1-liujunli@lixiang.com [ Gao Xiang: Use the original trace in v1. ] Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>

syzbot reported the splat below. [0] When nsim_queue_uninit() is called from nsim_init_netdevsim(), register_netdevice() has not been called, thus dev->dstats has not been allocated. Let's not call dev_dstats_rx_dropped_add() in such a case. [0] BUG: unable to handle page fault for address: ffff88809782c020 PF: supervisor write access in kernel mode PF: error_code(0x0002) - not-present page PGD 1b401067 P4D 1b401067 PUD 0 Oops: Oops: 0002 [#1] SMP KASAN NOPTI CPU: 3 UID: 0 PID: 8476 Comm: syz.1.251 Not tainted 6.16.0-syzkaller-06699-ge8d780dcd957 #0 PREEMPT(full) Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014 RIP: 0010:local_add arch/x86/include/asm/local.h:33 [inline] RIP: 0010:u64_stats_add include/linux/u64_stats_sync.h:89 [inline] RIP: 0010:dev_dstats_rx_dropped_add include/linux/netdevice.h:3027 [inline] RIP: 0010:nsim_queue_free+0xba/0x120 drivers/net/netdevsim/netdev.c:714 Code: 07 77 6c 4a 8d 3c ed 20 7e f1 8d 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 75 46 4a 03 1c ed 20 7e f1 8d <4c> 01 63 20 be 00 02 00 00 48 8d 3d 00 00 00 00 e8 61 2f 58 fa 48 RSP: 0018:ffffc900044af150 EFLAGS: 00010286 RAX: dffffc0000000000 RBX: ffff88809782c000 RCX: 00000000000079c3 RDX: 1ffffffff1be2fc7 RSI: ffffffff8c15f380 RDI: ffffffff8df17e38 RBP: ffff88805f59d000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000001 R12: 0000000000000000 R13: 0000000000000003 R14: ffff88806ceb3d00 R15: ffffed100dfd308e FS: 0000000000000000(0000) GS:ffff88809782c000(0063) knlGS:00000000f505db40 CS: 0010 DS: 002b ES: 002b CR0: 0000000080050033 CR2: ffff88809782c020 CR3: 000000006fc6a000 CR4: 0000000000352ef0 Call Trace: <TASK> nsim_queue_uninit drivers/net/netdevsim/netdev.c:993 [inline] nsim_init_netdevsim drivers/net/netdevsim/netdev.c:1049 [inline] nsim_create+0xd0a/0x1260 drivers/net/netdevsim/netdev.c:1101 __nsim_dev_port_add+0x435/0x7d0 drivers/net/netdevsim/dev.c:1438 nsim_dev_port_add_all drivers/net/netdevsim/dev.c:1494 [inline] nsim_dev_reload_create drivers/net/netdevsim/dev.c:1546 [inline] nsim_dev_reload_up+0x5b8/0x860 drivers/net/netdevsim/dev.c:1003 devlink_reload+0x322/0x7c0 net/devlink/dev.c:474 devlink_nl_reload_doit+0xe31/0x1410 net/devlink/dev.c:584 genl_family_rcv_msg_doit+0x206/0x2f0 net/netlink/genetlink.c:1115 genl_family_rcv_msg net/netlink/genetlink.c:1195 [inline] genl_rcv_msg+0x55c/0x800 net/netlink/genetlink.c:1210 netlink_rcv_skb+0x155/0x420 net/netlink/af_netlink.c:2552 genl_rcv+0x28/0x40 net/netlink/genetlink.c:1219 netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline] netlink_unicast+0x5aa/0x870 net/netlink/af_netlink.c:1346 netlink_sendmsg+0x8d1/0xdd0 net/netlink/af_netlink.c:1896 sock_sendmsg_nosec net/socket.c:714 [inline] __sock_sendmsg net/socket.c:729 [inline] ____sys_sendmsg+0xa95/0xc70 net/socket.c:2614 ___sys_sendmsg+0x134/0x1d0 net/socket.c:2668 __sys_sendmsg+0x16d/0x220 net/socket.c:2700 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline] __do_fast_syscall_32+0x7c/0x3a0 arch/x86/entry/syscall_32.c:306 do_fast_syscall_32+0x32/0x80 arch/x86/entry/syscall_32.c:331 entry_SYSENTER_compat_after_hwframe+0x84/0x8e RIP: 0023:0xf708e579 Code: b8 01 10 06 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 00 00 00 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 8d b4 26 00 00 00 00 8d b4 26 00 00 00 00 RSP: 002b:00000000f505d55c EFLAGS: 00000296 ORIG_RAX: 0000000000000172 RAX: ffffffffffffffda RBX: 0000000000000007 RCX: 0000000080000080 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000296 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 </TASK> Modules linked in: CR2: ffff88809782c020 Fixes: 2a68a22 ("netdevsim: account dropped packet length in stats on queue free") Reported-by: syzbot+8aa80c6232008f7b957d@syzkaller.appspotmail.com Closes: https://lore.kernel.org/netdev/688bb9ca.a00a0220.26d0e1.0050.GAE@google.com/ Suggested-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com> Link: https://patch.msgid.link/20250812162130.4129322-1-kuniyu@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Shuang reported sch_ets test-case [1] crashing in ets_class_qlen_notify() after recent changes from Lion [2]. The problem is: in ets_qdisc_change() we purge unused DWRR queues; the value of 'q->nbands' is the new one, and the cleanup should be done with the old one. The problem is here since my first attempts to fix ets_qdisc_change(), but it surfaced again after the recent qdisc len accounting fixes. Fix it purging idle DWRR queues before assigning a new value of 'q->nbands', so that all purge operations find a consistent configuration: - old 'q->nbands' because it's needed by ets_class_find() - old 'q->nstrict' because it's needed by ets_class_is_strict() BUG: kernel NULL pointer dereference, address: 0000000000000000 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 0 P4D 0 Oops: Oops: 0000 [#1] SMP NOPTI CPU: 62 UID: 0 PID: 39457 Comm: tc Kdump: loaded Not tainted 6.12.0-116.el10.x86_64 #1 PREEMPT(voluntary) Hardware name: Dell Inc. PowerEdge R640/06DKY5, BIOS 2.12.2 07/09/2021 RIP: 0010:__list_del_entry_valid_or_report+0x4/0x80 Code: ff 4c 39 c7 0f 84 39 19 8e ff b8 01 00 00 00 c3 cc cc cc cc 66 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa <48> 8b 17 48 8b 4f 08 48 85 d2 0f 84 56 19 8e ff 48 85 c9 0f 84 ab RSP: 0018:ffffba186009f400 EFLAGS: 00010202 RAX: 00000000000000d6 RBX: 0000000000000000 RCX: 0000000000000004 RDX: ffff9f0fa29b69c0 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffffffc12c2400 R08: 0000000000000008 R09: 0000000000000004 R10: ffffffffffffffff R11: 0000000000000004 R12: 0000000000000000 R13: ffff9f0f8cfe0000 R14: 0000000000100005 R15: 0000000000000000 FS: 00007f2154f37480(0000) GS:ffff9f269c1c0000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 00000001530be001 CR4: 00000000007726f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 PKRU: 55555554 Call Trace: <TASK> ets_class_qlen_notify+0x65/0x90 [sch_ets] qdisc_tree_reduce_backlog+0x74/0x110 ets_qdisc_change+0x630/0xa40 [sch_ets] __tc_modify_qdisc.constprop.0+0x216/0x7f0 tc_modify_qdisc+0x7c/0x120 rtnetlink_rcv_msg+0x145/0x3f0 netlink_rcv_skb+0x53/0x100 netlink_unicast+0x245/0x390 netlink_sendmsg+0x21b/0x470 ____sys_sendmsg+0x39d/0x3d0 ___sys_sendmsg+0x9a/0xe0 __sys_sendmsg+0x7a/0xd0 do_syscall_64+0x7d/0x160 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x7f2155114084 Code: 89 02 b8 ff ff ff ff eb bb 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 f3 0f 1e fa 80 3d 25 f0 0c 00 00 74 13 b8 2e 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 54 c3 0f 1f 00 48 83 ec 28 89 54 24 1c 48 89 RSP: 002b:00007fff1fd7a988 EFLAGS: 00000202 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 0000560ec063e5e0 RCX: 00007f2155114084 RDX: 0000000000000000 RSI: 00007fff1fd7a9f0 RDI: 0000000000000003 RBP: 00007fff1fd7aa60 R08: 0000000000000010 R09: 000000000000003f R10: 0000560ee9b3a010 R11: 0000000000000202 R12: 00007fff1fd7aae0 R13: 000000006891ccde R14: 0000560ec063e5e0 R15: 00007fff1fd7aad0 </TASK> [1] https://lore.kernel.org/netdev/e08c7f4a6882f260011909a868311c6e9b54f3e4.1639153474.git.dcaratti@redhat.com/ [2] https://lore.kernel.org/netdev/d912cbd7-193b-4269-9857-525bee8bbb6a@gmail.com/ Cc: stable@vger.kernel.org Fixes: 103406b ("net/sched: Always pass notifications when child class becomes empty") Fixes: c062f2a ("net/sched: sch_ets: don't remove idle classes from the round-robin list") Fixes: dcc68b4 ("net: sch_ets: Add a new Qdisc") Reported-by: Li Shuang <shuali@redhat.com> Closes: https://issues.redhat.com/browse/RHEL-108026 Reviewed-by: Petr Machata <petrm@nvidia.com> Co-developed-by: Ivan Vecera <ivecera@redhat.com> Signed-off-by: Ivan Vecera <ivecera@redhat.com> Signed-off-by: Davide Caratti <dcaratti@redhat.com> Link: https://patch.msgid.link/7928ff6d17db47a2ae7cc205c44777b1f1950545.1755016081.git.dcaratti@redhat.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>

On CPU offline the kernel stalled with below call trace: INFO: task kworker/0:1:11 blocked for more than 120 seconds. Tainted: G O 6.15.0-rc4+ #1 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/0:1 state:D stack:0 pid:11 tgid:11 ppid:2 task_flags:0x4208060 flags:0x00000008 Workqueue: events vmstat_shepherd Call trace: __switch_to+0x118/0x188 (T) __schedule+0x31c/0x1300 schedule+0x3c/0x120 percpu_rwsem_wait+0x12c/0x1b0 __percpu_down_read+0x78/0x188 cpus_read_lock+0xc4/0xe8 vmstat_shepherd+0x30/0x138 process_one_work+0x154/0x3c8 worker_thread+0x2e8/0x400 kthread+0x154/0x230 ret_from_fork+0x10/0x20 INFO: task kworker/1:1:116 blocked for more than 120 seconds. Tainted: G O 6.15.0-rc4+ #1 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/1:1 state:D stack:0 pid:116 tgid:116 ppid:2 task_flags:0x4208060 flags:0x00000008 Workqueue: events work_for_cpu_fn Call trace: __switch_to+0x118/0x188 (T) __schedule+0x31c/0x1300 schedule+0x3c/0x120 schedule_timeout+0x10c/0x120 __wait_for_common+0xc4/0x1b8 wait_for_completion+0x28/0x40 cpuhp_kick_ap_work+0x114/0x3c8 _cpu_down+0x130/0x4b8 __cpu_down_maps_locked+0x20/0x38 work_for_cpu_fn+0x24/0x40 process_one_work+0x154/0x3c8 worker_thread+0x2e8/0x400 kthread+0x154/0x230 ret_from_fork+0x10/0x20 cpuhp hold the cpu hotplug lock endless and stalled vmstat_shepherd. This is because we count nr_running twice on cpuhp enqueuing and failed the wait condition of cpuhp: enqueue_task_fair() // pick cpuhp from idle, rq->nr_running = 0 dl_server_start() [...] add_nr_running() // rq->nr_running = 1 add_nr_running() // rq->nr_running = 2 [switch to cpuhp, waiting on balance_hotplug_wait()] rcuwait_wait_event(rq->nr_running == 1 && ...) // failed, rq->nr_running=2 schedule() // wait again This doesn't make sense to count one single task twice on rq->nr_running. So fix this. Signed-off-by: Yicong Yang <yangyicong@hisilicon.com>

btrfs_subpage_set_writeback() calls folio_start_writeback() the first time a folio is written back, and it also clears the PAGECACHE_TAG_TOWRITE tag even if there are still dirty blocks in the folio. This can break ordering guarantees, such as those required by btrfs_wait_ordered_extents(). That ordering breakage leads to a real failure. For example, running generic/464 on a zoned setup will hit the following ASSERT. This happens because the broken ordering fails to flush existing dirty pages before the file size is truncated. assertion failed: !list_empty(&ordered->list) :: 0, in fs/btrfs/zoned.c:1899 ------------[ cut here ]------------ kernel BUG at fs/btrfs/zoned.c:1899! Oops: invalid opcode: 0000 [#1] SMP NOPTI CPU: 2 UID: 0 PID: 1906169 Comm: kworker/u130:2 Kdump: loaded Not tainted 6.16.0-rc6-BTRFS-ZNS+ #554 PREEMPT(voluntary) Hardware name: Supermicro Super Server/H12SSL-NT, BIOS 2.0 02/22/2021 Workqueue: btrfs-endio-write btrfs_work_helper [btrfs] RIP: 0010:btrfs_finish_ordered_zoned.cold+0x50/0x52 [btrfs] RSP: 0018:ffffc9002efdbd60 EFLAGS: 00010246 RAX: 000000000000004c RBX: ffff88811923c4e0 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffffffff827e38b1 RDI: 00000000ffffffff RBP: ffff88810005d000 R08: 00000000ffffdfff R09: ffffffff831051c8 R10: ffffffff83055220 R11: 0000000000000000 R12: ffff8881c2458c00 R13: ffff88811923c540 R14: ffff88811923c5e8 R15: ffff8881c1bd9680 FS: 0000000000000000(0000) GS:ffff88a04acd0000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f907c7a918c CR3: 0000000004024000 CR4: 0000000000350ef0 Call Trace: <TASK> ? srso_return_thunk+0x5/0x5f btrfs_finish_ordered_io+0x4a/0x60 [btrfs] btrfs_work_helper+0xf9/0x490 [btrfs] process_one_work+0x204/0x590 ? srso_return_thunk+0x5/0x5f worker_thread+0x1d6/0x3d0 ? __pfx_worker_thread+0x10/0x10 kthread+0x118/0x230 ? __pfx_kthread+0x10/0x10 ret_from_fork+0x205/0x260 ? __pfx_kthread+0x10/0x10 ret_from_fork_asm+0x1a/0x30 </TASK> Consider process A calling writepages() with WB_SYNC_NONE. In zoned mode or for compressed writes, it locks several folios for delalloc and starts writing them out. Let's call the last locked folio folio X. Suppose the write range only partially covers folio X, leaving some pages dirty. Process A calls btrfs_subpage_set_writeback() when building a bio. This function call clears the TOWRITE tag of folio X, whose size = 8K and the block size = 4K. It is following state. 0 4K 8K |/////|/////| (flag: DIRTY, tag: DIRTY) <-----> Process A will write this range. Now suppose process B concurrently calls writepages() with WB_SYNC_ALL. It calls tag_pages_for_writeback() to tag dirty folios with PAGECACHE_TAG_TOWRITE. Since folio X is still dirty, it gets tagged. Then, B collects tagged folios using filemap_get_folios_tag() and must wait for folio X to be written before returning from writepages(). 0 4K 8K |/////|/////| (flag: DIRTY, tag: DIRTY|TOWRITE) However, between tagging and collecting, process A may call btrfs_subpage_set_writeback() and clear folio X's TOWRITE tag. 0 4K 8K | |/////| (flag: DIRTY|WRITEBACK, tag: DIRTY) As a result, process B won't see folio X in its batch, and returns without waiting for it. This breaks the WB_SYNC_ALL ordering requirement. Fix this by using btrfs_subpage_set_writeback_keepwrite(), which retains the TOWRITE tag. We now manually clear the tag only after the folio becomes clean, via the xas operation. Fixes: 3470da3 ("btrfs: subpage: introduce helpers for writeback status") CC: stable@vger.kernel.org # 6.12+ Reviewed-by: Qu Wenruo <wqu@suse.com> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com> Signed-off-by: David Sterba <dsterba@suse.com>

An use-after-free issue occurred when __mark_inode_dirty() get the bdi_writeback that was in the progress of switching. CPU: 1 PID: 562 Comm: systemd-random- Not tainted 6.6.56-gb4403bd46a8e #1 ...... pstate: 60400005 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : __mark_inode_dirty+0x124/0x418 lr : __mark_inode_dirty+0x118/0x418 sp : ffffffc08c9dbbc0 ........ Call trace: __mark_inode_dirty+0x124/0x418 generic_update_time+0x4c/0x60 file_modified+0xcc/0xd0 ext4_buffered_write_iter+0x58/0x124 ext4_file_write_iter+0x54/0x704 vfs_write+0x1c0/0x308 ksys_write+0x74/0x10c __arm64_sys_write+0x1c/0x28 invoke_syscall+0x48/0x114 el0_svc_common.constprop.0+0xc0/0xe0 do_el0_svc+0x1c/0x28 el0_svc+0x40/0xe4 el0t_64_sync_handler+0x120/0x12c el0t_64_sync+0x194/0x198 Root cause is: systemd-random-seed kworker ---------------------------------------------------------------------- ___mark_inode_dirty inode_switch_wbs_work_fn spin_lock(&inode->i_lock); inode_attach_wb locked_inode_to_wb_and_lock_list get inode->i_wb spin_unlock(&inode->i_lock); spin_lock(&wb->list_lock) spin_lock(&inode->i_lock) inode_io_list_move_locked spin_unlock(&wb->list_lock) spin_unlock(&inode->i_lock) spin_lock(&old_wb->list_lock) inode_do_switch_wbs spin_lock(&inode->i_lock) inode->i_wb = new_wb spin_unlock(&inode->i_lock) spin_unlock(&old_wb->list_lock) wb_put_many(old_wb, nr_switched) cgwb_release old wb released wb_wakeup_delayed() accesses wb, then trigger the use-after-free issue Fix this race condition by holding inode spinlock until wb_wakeup_delayed() finished. Signed-off-by: Jiufei Xue <jiufei.xue@samsung.com> Link: https://lore.kernel.org/20250728100715.3863241-1-jiufei.xue@samsung.com Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Christian Brauner <brauner@kernel.org>

…dlock When a user creates a dualpi2 qdisc it automatically sets a timer. This timer will run constantly and update the qdisc's probability field. The issue is that the timer acquires the qdisc root lock and runs in hardirq. The qdisc root lock is also acquired in dev.c whenever a packet arrives for this qdisc. Since the dualpi2 timer callback runs in hardirq, it may interrupt the packet processing running in softirq. If that happens and it runs on the same CPU, it will acquire the same lock and cause a deadlock. The following splat shows up when running a kernel compiled with lock debugging: [ +0.000224] WARNING: inconsistent lock state [ +0.000224] 6.16.0+ #10 Not tainted [ +0.000169] -------------------------------- [ +0.000029] inconsistent {IN-HARDIRQ-W} -> {HARDIRQ-ON-W} usage. [ +0.000000] ping/156 [HC0[0]:SC0[2]:HE1:SE0] takes: [ +0.000000] ffff897841242110 (&sch->root_lock_key){?.-.}-{3:3}, at: __dev_queue_xmit+0x86d/0x1140 [ +0.000000] {IN-HARDIRQ-W} state was registered at: [ +0.000000] lock_acquire.part.0+0xb6/0x220 [ +0.000000] _raw_spin_lock+0x31/0x80 [ +0.000000] dualpi2_timer+0x6f/0x270 [ +0.000000] __hrtimer_run_queues+0x1c5/0x360 [ +0.000000] hrtimer_interrupt+0x115/0x260 [ +0.000000] __sysvec_apic_timer_interrupt+0x6d/0x1a0 [ +0.000000] sysvec_apic_timer_interrupt+0x6e/0x80 [ +0.000000] asm_sysvec_apic_timer_interrupt+0x1a/0x20 [ +0.000000] pv_native_safe_halt+0xf/0x20 [ +0.000000] default_idle+0x9/0x10 [ +0.000000] default_idle_call+0x7e/0x1e0 [ +0.000000] do_idle+0x1e8/0x250 [ +0.000000] cpu_startup_entry+0x29/0x30 [ +0.000000] rest_init+0x151/0x160 [ +0.000000] start_kernel+0x6f3/0x700 [ +0.000000] x86_64_start_reservations+0x24/0x30 [ +0.000000] x86_64_start_kernel+0xc8/0xd0 [ +0.000000] common_startup_64+0x13e/0x148 [ +0.000000] irq event stamp: 6884 [ +0.000000] hardirqs last enabled at (6883): [<ffffffffa75700b3>] neigh_resolve_output+0x223/0x270 [ +0.000000] hardirqs last disabled at (6882): [<ffffffffa7570078>] neigh_resolve_output+0x1e8/0x270 [ +0.000000] softirqs last enabled at (6880): [<ffffffffa757006b>] neigh_resolve_output+0x1db/0x270 [ +0.000000] softirqs last disabled at (6884): [<ffffffffa755b533>] __dev_queue_xmit+0x73/0x1140 [ +0.000000] other info that might help us debug this: [ +0.000000] Possible unsafe locking scenario: [ +0.000000] CPU0 [ +0.000000] ---- [ +0.000000] lock(&sch->root_lock_key); [ +0.000000] <Interrupt> [ +0.000000] lock(&sch->root_lock_key); [ +0.000000] *** DEADLOCK *** [ +0.000000] 4 locks held by ping/156: [ +0.000000] #0: ffff897842332e08 (sk_lock-AF_INET){+.+.}-{0:0}, at: raw_sendmsg+0x41e/0xf40 [ +0.000000] #1: ffffffffa816f880 (rcu_read_lock){....}-{1:3}, at: ip_output+0x2c/0x190 [ +0.000000] #2: ffffffffa816f880 (rcu_read_lock){....}-{1:3}, at: ip_finish_output2+0xad/0x950 [ +0.000000] #3: ffffffffa816f840 (rcu_read_lock_bh){....}-{1:3}, at: __dev_queue_xmit+0x73/0x1140 I am able to reproduce it consistently when running the following: tc qdisc add dev lo handle 1: root dualpi2 ping -f 127.0.0.1 To fix it, make the timer run in softirq. Fixes: 320d031 ("sched: Struct definition and parsing of dualpi2 qdisc") Reviewed-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: Victor Nogueira <victor@mojatatu.com> Link: https://patch.msgid.link/20250815135317.664993-1-victor@mojatatu.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>

BPF CI testing report a UAF issue: [ 16.446633] BUG: kernel NULL pointer dereference, address: 000000000000003 0 [ 16.447134] #PF: supervisor read access in kernel mod e [ 16.447516] #PF: error_code(0x0000) - not-present pag e [ 16.447878] PGD 0 P4D 0 [ 16.448063] Oops: Oops: 0000 [#1] PREEMPT SMP NOPT I [ 16.448409] CPU: 0 UID: 0 PID: 9 Comm: kworker/0:1 Tainted: G OE 6.13.0-rc3-g89e8a75fda73-dirty #4 2 [ 16.449124] Tainted: [O]=OOT_MODULE, [E]=UNSIGNED_MODUL E [ 16.449502] Hardware name: QEMU Ubuntu 24.04 PC (i440FX + PIIX, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/201 4 [ 16.450201] Workqueue: smc_hs_wq smc_listen_wor k [ 16.450531] RIP: 0010:smc_listen_work+0xc02/0x159 0 [ 16.452158] RSP: 0018:ffffb5ab40053d98 EFLAGS: 0001024 6 [ 16.452526] RAX: 0000000000000001 RBX: 0000000000000002 RCX: 000000000000030 0 [ 16.452994] RDX: 0000000000000280 RSI: 00003513840053f0 RDI: 000000000000000 0 [ 16.453492] RBP: ffffa097808e3800 R08: ffffa09782dba1e0 R09: 000000000000000 5 [ 16.453987] R10: 0000000000000000 R11: 0000000000000000 R12: ffffa0978274640 0 [ 16.454497] R13: 0000000000000000 R14: 0000000000000000 R15: ffffa09782d4092 0 [ 16.454996] FS: 0000000000000000(0000) GS:ffffa097bbc00000(0000) knlGS:000000000000000 0 [ 16.455557] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003 3 [ 16.455961] CR2: 0000000000000030 CR3: 0000000102788004 CR4: 0000000000770ef 0 [ 16.456459] PKRU: 5555555 4 [ 16.456654] Call Trace : [ 16.456832] <TASK > [ 16.456989] ? __die+0x23/0x7 0 [ 16.457215] ? page_fault_oops+0x180/0x4c 0 [ 16.457508] ? __lock_acquire+0x3e6/0x249 0 [ 16.457801] ? exc_page_fault+0x68/0x20 0 [ 16.458080] ? asm_exc_page_fault+0x26/0x3 0 [ 16.458389] ? smc_listen_work+0xc02/0x159 0 [ 16.458689] ? smc_listen_work+0xc02/0x159 0 [ 16.458987] ? lock_is_held_type+0x8f/0x10 0 [ 16.459284] process_one_work+0x1ea/0x6d 0 [ 16.459570] worker_thread+0x1c3/0x38 0 [ 16.459839] ? __pfx_worker_thread+0x10/0x1 0 [ 16.460144] kthread+0xe0/0x11 0 [ 16.460372] ? __pfx_kthread+0x10/0x1 0 [ 16.460640] ret_from_fork+0x31/0x5 0 [ 16.460896] ? __pfx_kthread+0x10/0x1 0 [ 16.461166] ret_from_fork_asm+0x1a/0x3 0 [ 16.461453] </TASK > [ 16.461616] Modules linked in: bpf_testmod(OE) [last unloaded: bpf_testmod(OE) ] [ 16.462134] CR2: 000000000000003 0 [ 16.462380] ---[ end trace 0000000000000000 ]--- [ 16.462710] RIP: 0010:smc_listen_work+0xc02/0x1590 The direct cause of this issue is that after smc_listen_out_connected(), newclcsock->sk may be NULL since it will releases the smcsk. Therefore, if the application closes the socket immediately after accept, newclcsock->sk can be NULL. A possible execution order could be as follows: smc_listen_work | userspace ----------------------------------------------------------------- lock_sock(sk) | smc_listen_out_connected() | | \- smc_listen_out | | | \- release_sock | | |- sk->sk_data_ready() | | fd = accept(); | close(fd); | \- socket->sk = NULL; /* newclcsock->sk is NULL now */ SMC_STAT_SERV_SUCC_INC(sock_net(newclcsock->sk)) Since smc_listen_out_connected() will not fail, simply swapping the order of the code can easily fix this issue. Fixes: 3b2dec2 ("net/smc: restructure client and server code in af_smc") Signed-off-by: D. Wythe <alibuda@linux.alibaba.com> Reviewed-by: Guangguan Wang <guangguan.wang@linux.alibaba.com> Reviewed-by: Alexandra Winter <wintera@linux.ibm.com> Reviewed-by: Dust Li <dust.li@linux.alibaba.com> Link: https://patch.msgid.link/20250818054618.41615-1-alibuda@linux.alibaba.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Receiving HSR frame with insufficient space to hold HSR tag in the skb can result in a crash (kernel BUG): [ 45.390915] skbuff: skb_under_panic: text:ffffffff86f32cac len:26 put:14 head:ffff888042418000 data:ffff888042417ff4 tail:0xe end:0x180 dev:bridge_slave_1 [ 45.392559] ------------[ cut here ]------------ [ 45.392912] kernel BUG at net/core/skbuff.c:211! [ 45.393276] Oops: invalid opcode: 0000 [#1] SMP DEBUG_PAGEALLOC KASAN NOPTI [ 45.393809] CPU: 1 UID: 0 PID: 2496 Comm: reproducer Not tainted 6.15.0 #12 PREEMPT(undef) [ 45.394433] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014 [ 45.395273] RIP: 0010:skb_panic+0x15b/0x1d0 <snip registers, remove unreliable trace> [ 45.402911] Call Trace: [ 45.403105] <IRQ> [ 45.404470] skb_push+0xcd/0xf0 [ 45.404726] br_dev_queue_push_xmit+0x7c/0x6c0 [ 45.406513] br_forward_finish+0x128/0x260 [ 45.408483] __br_forward+0x42d/0x590 [ 45.409464] maybe_deliver+0x2eb/0x420 [ 45.409763] br_flood+0x174/0x4a0 [ 45.410030] br_handle_frame_finish+0xc7c/0x1bc0 [ 45.411618] br_handle_frame+0xac3/0x1230 [ 45.413674] __netif_receive_skb_core.constprop.0+0x808/0x3df0 [ 45.422966] __netif_receive_skb_one_core+0xb4/0x1f0 [ 45.424478] __netif_receive_skb+0x22/0x170 [ 45.424806] process_backlog+0x242/0x6d0 [ 45.425116] __napi_poll+0xbb/0x630 [ 45.425394] net_rx_action+0x4d1/0xcc0 [ 45.427613] handle_softirqs+0x1a4/0x580 [ 45.427926] do_softirq+0x74/0x90 [ 45.428196] </IRQ> This issue was found by syzkaller. The panic happens in br_dev_queue_push_xmit() once it receives a corrupted skb with ETH header already pushed in linear data. When it attempts the skb_push() call, there's not enough headroom and skb_push() panics. The corrupted skb is put on the queue by HSR layer, which makes a sequence of unintended transformations when it receives a specific corrupted HSR frame (with incomplete TAG). Fix it by dropping and consuming frames that are not long enough to contain both ethernet and hsr headers. Alternative fix would be to check for enough headroom before skb_push() in br_dev_queue_push_xmit(). In the reproducer, this is injected via AF_PACKET, but I don't easily see why it couldn't be sent over the wire from adjacent network. Further Details: In the reproducer, the following network interface chain is set up: ┌────────────────┐ ┌────────────────┐ │ veth0_to_hsr ├───┤ hsr_slave0 ┼───┐ └────────────────┘ └────────────────┘ │ │ ┌──────┐ ├─┤ hsr0 ├───┐ │ └──────┘ │ ┌────────────────┐ ┌────────────────┐ │ │┌────────┐ │ veth1_to_hsr ┼───┤ hsr_slave1 ├───┘ └┤ │ └────────────────┘ └────────────────┘ ┌┼ bridge │ ││ │ │└────────┘ │ ┌───────┐ │ │ ... ├──────┘ └───────┘ To trigger the events leading up to crash, reproducer sends a corrupted HSR frame with incomplete TAG, via AF_PACKET socket on 'veth0_to_hsr'. The first HSR-layer function to process this frame is hsr_handle_frame(). It and then checks if the protocol is ETH_P_PRP or ETH_P_HSR. If it is, it calls skb_set_network_header(skb, ETH_HLEN + HSR_HLEN), without checking that the skb is long enough. For the crashing frame it is not, and hence the skb->network_header and skb->mac_len fields are set incorrectly, pointing after the end of the linear buffer. I will call this a BUG#1 and it is what is addressed by this patch. In the crashing scenario before the fix, the skb continues to go down the hsr path as follows. hsr_handle_frame() then calls this sequence hsr_forward_skb() fill_frame_info() hsr->proto_ops->fill_frame_info() hsr_fill_frame_info() hsr_fill_frame_info() contains a check that intends to check whether the skb actually contains the HSR header. But the check relies on the skb->mac_len field which was erroneously setup due to BUG#1, so the check passes and the execution continues back in the hsr_forward_skb(): hsr_forward_skb() hsr_forward_do() hsr->proto_ops->get_untagged_frame() hsr_get_untagged_frame() create_stripped_skb_hsr() In create_stripped_skb_hsr(), a copy of the skb is created and is further corrupted by operation that attempts to strip the HSR tag in a call to __pskb_copy(). The skb enters create_stripped_skb_hsr() with ethernet header pushed in linear buffer. The skb_pull(skb_in, HSR_HLEN) thus pulls 6 bytes of ethernet header into the headroom, creating skb_in with a headroom of size 8. The subsequent __pskb_copy() then creates an skb with headroom of just 2 and skb->len of just 12, this is how it looks after the copy: gdb) p skb->len $10 = 12 (gdb) p skb->data $11 = (unsigned char *) 0xffff888041e45382 "\252\252\252\252\252!\210\373", (gdb) p skb->head $12 = (unsigned char *) 0xffff888041e45380 "" It seems create_stripped_skb_hsr() assumes that ETH header is pulled in the headroom when it's entered, because it just pulls HSR header on top. But that is not the case in our code-path and we end up with the corrupted skb instead. I will call this BUG#2 *I got confused here because it seems that under no conditions can create_stripped_skb_hsr() work well, the assumption it makes is not true during the processing of hsr frames - since the skb_push() in hsr_handle_frame to skb_pull in hsr_deliver_master(). I wonder whether I missed something here.* Next, the execution arrives in hsr_deliver_master(). It calls skb_pull(ETH_HLEN), which just returns NULL - the SKB does not have enough space for the pull (as it only has 12 bytes in total at this point). *The skb_pull() here further suggests that ethernet header is meant to be pushed through the whole hsr processing and create_stripped_skb_hsr() should pull it before doing the HSR header pull.* hsr_deliver_master() then puts the corrupted skb on the queue, it is then picked up from there by bridge frame handling layer and finally lands in br_dev_queue_push_xmit where it panics. Cc: stable@kernel.org Fixes: 48b491a ("net: hsr: fix mac_len checks") Reported-by: syzbot+a81f2759d022496b40ab@syzkaller.appspotmail.com Signed-off-by: Jakub Acs <acsjakub@amazon.de> Reviewed-by: Eric Dumazet <edumazet@google.com> Link: https://patch.msgid.link/20250819082842.94378-1-acsjakub@amazon.de Signed-off-by: Jakub Kicinski <kuba@kernel.org>

The mm/debug_vm_pagetable test allocates manually page table entries for the tests it runs, using also its manually allocated mm_struct. That in itself is ok, but when it exits, at destroy_args() it fails to clear those entries with the *_clear functions. The problem is that leaves stale entries. If another process allocates an mm_struct with a pgd at the same address, it may end up running into the stale entry. This is happening in practice on a debug kernel with CONFIG_DEBUG_VM_PGTABLE=y, for example this is the output with some extra debugging I added (it prints a warning trace if pgtables_bytes goes negative, in addition to the warning at check_mm() function): [ 2.539353] debug_vm_pgtable: [get_random_vaddr ]: random_vaddr is 0x7ea247140000 [ 2.539366] kmem_cache info [ 2.539374] kmem_cachep 0x000000002ce82385 - freelist 0x0000000000000000 - offset 0x508 [ 2.539447] debug_vm_pgtable: [init_args ]: args->mm is 0x000000002267cc9e (...) [ 2.552800] WARNING: CPU: 5 PID: 116 at include/linux/mm.h:2841 free_pud_range+0x8bc/0x8d0 [ 2.552816] Modules linked in: [ 2.552843] CPU: 5 UID: 0 PID: 116 Comm: modprobe Not tainted 6.12.0-105.debug_vm2.el10.ppc64le+debug #1 VOLUNTARY [ 2.552859] Hardware name: IBM,9009-41A POWER9 (architected) 0x4e0202 0xf000005 of:IBM,FW910.00 (VL910_062) hv:phyp pSeries [ 2.552872] NIP: c0000000007eef3c LR: c0000000007eef30 CTR: c0000000003d8c90 [ 2.552885] REGS: c0000000622e73b0 TRAP: 0700 Not tainted (6.12.0-105.debug_vm2.el10.ppc64le+debug) [ 2.552899] MSR: 800000000282b033 <SF,VEC,VSX,EE,FP,ME,IR,DR,RI,LE> CR: 24002822 XER: 0000000a [ 2.552954] CFAR: c0000000008f03f0 IRQMASK: 0 [ 2.552954] GPR00: c0000000007eef30 c0000000622e7650 c000000002b1ac00 0000000000000001 [ 2.552954] GPR04: 0000000000000008 0000000000000000 c0000000007eef30 ffffffffffffffff [ 2.552954] GPR08: 00000000ffff00f5 0000000000000001 0000000000000048 0000000000004000 [ 2.552954] GPR12: 00000003fa440000 c000000017ffa300 c0000000051d9f80 ffffffffffffffdb [ 2.552954] GPR16: 0000000000000000 0000000000000008 000000000000000a 60000000000000e0 [ 2.552954] GPR20: 4080000000000000 c0000000113af038 00007fffcf130000 0000700000000000 [ 2.552954] GPR24: c000000062a6a000 0000000000000001 8000000062a68000 0000000000000001 [ 2.552954] GPR28: 000000000000000a c000000062ebc600 0000000000002000 c000000062ebc760 [ 2.553170] NIP [c0000000007eef3c] free_pud_range+0x8bc/0x8d0 [ 2.553185] LR [c0000000007eef30] free_pud_range+0x8b0/0x8d0 [ 2.553199] Call Trace: [ 2.553207] [c0000000622e7650] [c0000000007eef30] free_pud_range+0x8b0/0x8d0 (unreliable) [ 2.553229] [c0000000622e7750] [c0000000007f40b4] free_pgd_range+0x284/0x3b0 [ 2.553248] [c0000000622e7800] [c0000000007f4630] free_pgtables+0x450/0x570 [ 2.553274] [c0000000622e78e0] [c0000000008161c0] exit_mmap+0x250/0x650 [ 2.553292] [c0000000622e7a30] [c0000000001b95b8] __mmput+0x98/0x290 [ 2.558344] [c0000000622e7a80] [c0000000001d1018] exit_mm+0x118/0x1b0 [ 2.558361] [c0000000622e7ac0] [c0000000001d141c] do_exit+0x2ec/0x870 [ 2.558376] [c0000000622e7b60] [c0000000001d1ca8] do_group_exit+0x88/0x150 [ 2.558391] [c0000000622e7bb0] [c0000000001d1db8] sys_exit_group+0x48/0x50 [ 2.558407] [c0000000622e7be0] [c00000000003d810] system_call_exception+0x1e0/0x4c0 [ 2.558423] [c0000000622e7e50] [c00000000000d05c] system_call_vectored_common+0x15c/0x2ec (...) [ 2.558892] ---[ end trace 0000000000000000 ]--- [ 2.559022] BUG: Bad rss-counter state mm:000000002267cc9e type:MM_ANONPAGES val:1 [ 2.559037] BUG: non-zero pgtables_bytes on freeing mm: -6144 Here the modprobe process ended up with an allocated mm_struct from the mm_struct slab that was used before by the debug_vm_pgtable test. That is not a problem, since the mm_struct is initialized again etc., however, if it ends up using the same pgd table, it bumps into the old stale entry when clearing/freeing the page table entries, so it tries to free an entry already gone (that one which was allocated by the debug_vm_pgtable test), which also explains the negative pgtables_bytes since it's accounting for not allocated entries in the current process. As far as I looked pgd_{alloc,free} etc. does not clear entries, and clearing of the entries is explicitly done in the free_pgtables-> free_pgd_range->free_p4d_range->free_pud_range->free_pmd_range-> free_pte_range path. However, the debug_vm_pgtable test does not call free_pgtables, since it allocates mm_struct and entries manually for its test and eg. not goes through page faults. So it also should clear manually the entries before exit at destroy_args(). This problem was noticed on a reboot X number of times test being done on a powerpc host, with a debug kernel with CONFIG_DEBUG_VM_PGTABLE enabled. Depends on the system, but on a 100 times reboot loop the problem could manifest once or twice, if a process ends up getting the right mm->pgd entry with the stale entries used by mm/debug_vm_pagetable. After using this patch, I couldn't reproduce/experience the problems anymore. I was able to reproduce the problem as well on latest upstream kernel (6.16). I also modified destroy_args() to use mmput() instead of mmdrop(), there is no reason to hold mm_users reference and not release the mm_struct entirely, and in the output above with my debugging prints I already had patched it to use mmput, it did not fix the problem, but helped in the debugging as well. Link: https://lkml.kernel.org/r/20250731214051.4115182-1-herton@redhat.com Fixes: 3c9b84f ("mm/debug_vm_pgtable: introduce struct pgtable_debug_args") Signed-off-by: Herton R. Krzesinski <herton@redhat.com> Cc: Anshuman Khandual <anshuman.khandual@arm.com> Cc: Christophe Leroy <christophe.leroy@csgroup.eu> Cc: Gavin Shan <gshan@redhat.com> Cc: Gerald Schaefer <gerald.schaefer@linux.ibm.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

Commit 3c7ac40 ("scsi: ufs: core: Delegate the interrupt service routine to a threaded IRQ handler") introduced an IRQ lock inversion issue. Fix this lock inversion by changing the spin_lock_irq() calls into spin_lock_irqsave() calls in code that can be called either from interrupt context or from thread context. This patch fixes the following lockdep complaint: WARNING: possible irq lock inversion dependency detected 6.12.30-android16-5-maybe-dirty-4k #1 Tainted: G W OE -------------------------------------------------------- kworker/u28:0/12 just changed the state of lock: ffffff881e29dd60 (&hba->clk_gating.lock){-...}-{2:2}, at: ufshcd_release_scsi_cmd+0x60/0x110 but this lock took another, HARDIRQ-unsafe lock in the past: (shost->host_lock){+.+.}-{2:2} and interrupts could create inverse lock ordering between them. other info that might help us debug this: Possible interrupt unsafe locking scenario: CPU0 CPU1 ---- ---- lock(shost->host_lock); local_irq_disable(); lock(&hba->clk_gating.lock); lock(shost->host_lock); <Interrupt> lock(&hba->clk_gating.lock); *** DEADLOCK *** 4 locks held by kworker/u28:0/12: #0: ffffff8800ac6158 ((wq_completion)async){+.+.}-{0:0}, at: process_one_work+0x1bc/0x65c #1: ffffffc085c93d70 ((work_completion)(&entry->work)){+.+.}-{0:0}, at: process_one_work+0x1e4/0x65c #2: ffffff881e29c0e0 (&shost->scan_mutex){+.+.}-{3:3}, at: __scsi_add_device+0x74/0x120 #3: ffffff881960ea00 (&hwq->cq_lock){-...}-{2:2}, at: ufshcd_mcq_poll_cqe_lock+0x28/0x104 the shortest dependencies between 2nd lock and 1st lock: -> (shost->host_lock){+.+.}-{2:2} { HARDIRQ-ON-W at: lock_acquire+0x134/0x2b4 _raw_spin_lock+0x48/0x64 ufshcd_sl_intr+0x4c/0xa08 ufshcd_threaded_intr+0x70/0x12c irq_thread_fn+0x48/0xa8 irq_thread+0x130/0x1ec kthread+0x110/0x134 ret_from_fork+0x10/0x20 SOFTIRQ-ON-W at: lock_acquire+0x134/0x2b4 _raw_spin_lock+0x48/0x64 ufshcd_sl_intr+0x4c/0xa08 ufshcd_threaded_intr+0x70/0x12c irq_thread_fn+0x48/0xa8 irq_thread+0x130/0x1ec kthread+0x110/0x134 ret_from_fork+0x10/0x20 INITIAL USE at: lock_acquire+0x134/0x2b4 _raw_spin_lock+0x48/0x64 ufshcd_sl_intr+0x4c/0xa08 ufshcd_threaded_intr+0x70/0x12c irq_thread_fn+0x48/0xa8 irq_thread+0x130/0x1ec kthread+0x110/0x134 ret_from_fork+0x10/0x20 } ... key at: [<ffffffc085ba1a98>] scsi_host_alloc.__key+0x0/0x10 ... acquired at: _raw_spin_lock_irqsave+0x5c/0x80 __ufshcd_release+0x78/0x118 ufshcd_send_uic_cmd+0xe4/0x118 ufshcd_dme_set_attr+0x88/0x1c8 ufs_google_phy_initialization+0x68/0x418 [ufs] ufs_google_link_startup_notify+0x78/0x27c [ufs] ufshcd_link_startup+0x84/0x720 ufshcd_init+0xf3c/0x1330 ufshcd_pltfrm_init+0x728/0x7d8 ufs_google_probe+0x30/0x84 [ufs] platform_probe+0xa0/0xe0 really_probe+0x114/0x454 __driver_probe_device+0xa4/0x160 driver_probe_device+0x44/0x23c __driver_attach_async_helper+0x60/0xd4 async_run_entry_fn+0x4c/0x17c process_one_work+0x26c/0x65c worker_thread+0x33c/0x498 kthread+0x110/0x134 ret_from_fork+0x10/0x20 -> (&hba->clk_gating.lock){-...}-{2:2} { IN-HARDIRQ-W at: lock_acquire+0x134/0x2b4 _raw_spin_lock_irqsave+0x5c/0x80 ufshcd_release_scsi_cmd+0x60/0x110 ufshcd_compl_one_cqe+0x2c0/0x3f4 ufshcd_mcq_poll_cqe_lock+0xb0/0x104 ufs_google_mcq_intr+0x80/0xa0 [ufs] __handle_irq_event_percpu+0x104/0x32c handle_irq_event+0x40/0x9c handle_fasteoi_irq+0x170/0x2e8 generic_handle_domain_irq+0x58/0x80 gic_handle_irq+0x48/0x104 call_on_irq_stack+0x3c/0x50 do_interrupt_handler+0x7c/0xd8 el1_interrupt+0x34/0x58 el1h_64_irq_handler+0x18/0x24 el1h_64_irq+0x68/0x6c _raw_spin_unlock_irqrestore+0x3c/0x6c debug_object_assert_init+0x16c/0x21c __mod_timer+0x4c/0x48c schedule_timeout+0xd4/0x16c io_schedule_timeout+0x48/0x70 do_wait_for_common+0x100/0x194 wait_for_completion_io_timeout+0x48/0x6c blk_execute_rq+0x124/0x17c scsi_execute_cmd+0x18c/0x3f8 scsi_probe_and_add_lun+0x204/0xd74 __scsi_add_device+0xbc/0x120 ufshcd_async_scan+0x80/0x3c0 async_run_entry_fn+0x4c/0x17c process_one_work+0x26c/0x65c worker_thread+0x33c/0x498 kthread+0x110/0x134 ret_from_fork+0x10/0x20 INITIAL USE at: lock_acquire+0x134/0x2b4 _raw_spin_lock_irqsave+0x5c/0x80 ufshcd_hold+0x34/0x14c ufshcd_send_uic_cmd+0x28/0x118 ufshcd_dme_set_attr+0x88/0x1c8 ufs_google_phy_initialization+0x68/0x418 [ufs] ufs_google_link_startup_notify+0x78/0x27c [ufs] ufshcd_link_startup+0x84/0x720 ufshcd_init+0xf3c/0x1330 ufshcd_pltfrm_init+0x728/0x7d8 ufs_google_probe+0x30/0x84 [ufs] platform_probe+0xa0/0xe0 really_probe+0x114/0x454 __driver_probe_device+0xa4/0x160 driver_probe_device+0x44/0x23c __driver_attach_async_helper+0x60/0xd4 async_run_entry_fn+0x4c/0x17c process_one_work+0x26c/0x65c worker_thread+0x33c/0x498 kthread+0x110/0x134 ret_from_fork+0x10/0x20 } ... key at: [<ffffffc085ba6fe8>] ufshcd_init.__key+0x0/0x10 ... acquired at: mark_lock+0x1c4/0x224 __lock_acquire+0x438/0x2e1c lock_acquire+0x134/0x2b4 _raw_spin_lock_irqsave+0x5c/0x80 ufshcd_release_scsi_cmd+0x60/0x110 ufshcd_compl_one_cqe+0x2c0/0x3f4 ufshcd_mcq_poll_cqe_lock+0xb0/0x104 ufs_google_mcq_intr+0x80/0xa0 [ufs] __handle_irq_event_percpu+0x104/0x32c handle_irq_event+0x40/0x9c handle_fasteoi_irq+0x170/0x2e8 generic_handle_domain_irq+0x58/0x80 gic_handle_irq+0x48/0x104 call_on_irq_stack+0x3c/0x50 do_interrupt_handler+0x7c/0xd8 el1_interrupt+0x34/0x58 el1h_64_irq_handler+0x18/0x24 el1h_64_irq+0x68/0x6c _raw_spin_unlock_irqrestore+0x3c/0x6c debug_object_assert_init+0x16c/0x21c __mod_timer+0x4c/0x48c schedule_timeout+0xd4/0x16c io_schedule_timeout+0x48/0x70 do_wait_for_common+0x100/0x194 wait_for_completion_io_timeout+0x48/0x6c blk_execute_rq+0x124/0x17c scsi_execute_cmd+0x18c/0x3f8 scsi_probe_and_add_lun+0x204/0xd74 __scsi_add_device+0xbc/0x120 ufshcd_async_scan+0x80/0x3c0 async_run_entry_fn+0x4c/0x17c process_one_work+0x26c/0x65c worker_thread+0x33c/0x498 kthread+0x110/0x134 ret_from_fork+0x10/0x20 stack backtrace: CPU: 6 UID: 0 PID: 12 Comm: kworker/u28:0 Tainted: G W OE 6.12.30-android16-5-maybe-dirty-4k #1 ccd4020fe444bdf629efc3b86df6be920b8df7d0 Tainted: [W]=WARN, [O]=OOT_MODULE, [E]=UNSIGNED_MODULE Hardware name: Spacecraft board based on MALIBU (DT) Workqueue: async async_run_entry_fn Call trace: dump_backtrace+0xfc/0x17c show_stack+0x18/0x28 dump_stack_lvl+0x40/0xa0 dump_stack+0x18/0x24 print_irq_inversion_bug+0x2fc/0x304 mark_lock_irq+0x388/0x4fc mark_lock+0x1c4/0x224 __lock_acquire+0x438/0x2e1c lock_acquire+0x134/0x2b4 _raw_spin_lock_irqsave+0x5c/0x80 ufshcd_release_scsi_cmd+0x60/0x110 ufshcd_compl_one_cqe+0x2c0/0x3f4 ufshcd_mcq_poll_cqe_lock+0xb0/0x104 ufs_google_mcq_intr+0x80/0xa0 [ufs dd6f385554e109da094ab91d5f7be18625a2222a] __handle_irq_event_percpu+0x104/0x32c handle_irq_event+0x40/0x9c handle_fasteoi_irq+0x170/0x2e8 generic_handle_domain_irq+0x58/0x80 gic_handle_irq+0x48/0x104 call_on_irq_stack+0x3c/0x50 do_interrupt_handler+0x7c/0xd8 el1_interrupt+0x34/0x58 el1h_64_irq_handler+0x18/0x24 el1h_64_irq+0x68/0x6c _raw_spin_unlock_irqrestore+0x3c/0x6c debug_object_assert_init+0x16c/0x21c __mod_timer+0x4c/0x48c schedule_timeout+0xd4/0x16c io_schedule_timeout+0x48/0x70 do_wait_for_common+0x100/0x194 wait_for_completion_io_timeout+0x48/0x6c blk_execute_rq+0x124/0x17c scsi_execute_cmd+0x18c/0x3f8 scsi_probe_and_add_lun+0x204/0xd74 __scsi_add_device+0xbc/0x120 ufshcd_async_scan+0x80/0x3c0 async_run_entry_fn+0x4c/0x17c process_one_work+0x26c/0x65c worker_thread+0x33c/0x498 kthread+0x110/0x134 ret_from_fork+0x10/0x20 Cc: Neil Armstrong <neil.armstrong@linaro.org> Cc: André Draszik <andre.draszik@linaro.org> Reviewed-by: Peter Wang <peter.wang@mediatek.com> Fixes: 3c7ac40 ("scsi: ufs: core: Delegate the interrupt service routine to a threaded IRQ handler") Signed-off-by: Bart Van Assche <bvanassche@acm.org> Link: https://lore.kernel.org/r/20250815155842.472867-2-bvanassche@acm.org Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

These iterations require the read lock, otherwise RCU lockdep will splat: ============================= WARNING: suspicious RCU usage 6.17.0-rc3-00014-g31419c045d64 #6 Tainted: G O ----------------------------- drivers/base/power/main.c:1333 RCU-list traversed in non-reader section!! other info that might help us debug this: rcu_scheduler_active = 2, debug_locks = 1 5 locks held by rtcwake/547: #0: 00000000643ab418 (sb_writers#6){.+.+}-{0:0}, at: file_start_write+0x2b/0x3a #1: 0000000067a0ca88 (&of->mutex#2){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x181/0x24b #2: 00000000631eac40 (kn->active#3){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x191/0x24b #3: 00000000609a1308 (system_transition_mutex){+.+.}-{4:4}, at: pm_suspend+0xaf/0x30b #4: 0000000060c0fdb0 (device_links_srcu){.+.+}-{0:0}, at: device_links_read_lock+0x75/0x98 stack backtrace: CPU: 0 UID: 0 PID: 547 Comm: rtcwake Tainted: G O 6.17.0-rc3-00014-g31419c045d64 #6 VOLUNTARY Tainted: [O]=OOT_MODULE Stack: 223721b3a80 6089eac6 00000001 00000001 ffffff00 6089eac6 00000535 6086e528 721b3ac0 6003c294 00000000 60031fc0 Call Trace: [<600407ed>] show_stack+0x10e/0x127 [<6003c294>] dump_stack_lvl+0x77/0xc6 [<6003c2fd>] dump_stack+0x1a/0x20 [<600bc2f8>] lockdep_rcu_suspicious+0x116/0x13e [<603d8ea1>] dpm_async_suspend_superior+0x117/0x17e [<603d980f>] device_suspend+0x528/0x541 [<603da24b>] dpm_suspend+0x1a2/0x267 [<603da837>] dpm_suspend_start+0x5d/0x72 [<600ca0c9>] suspend_devices_and_enter+0xab/0x736 [...] Add the fourth argument to the iteration to annotate this and avoid the splat. Fixes: 0679963 ("PM: sleep: Make async suspend handle suppliers like parents") Fixes: ed18738 ("PM: sleep: Make async resume handle consumers like children") Signed-off-by: Johannes Berg <johannes.berg@intel.com> Link: https://patch.msgid.link/20250826134348.aba79f6e6299.I9ecf55da46ccf33778f2c018a82e1819d815b348@changeid Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

syzbot reported the splat below. [0] When atmtcp_v_open() or atmtcp_v_close() is called via connect() or close(), atmtcp_send_control() is called to send an in-kernel special message. The message has ATMTCP_HDR_MAGIC in atmtcp_control.hdr.length. Also, a pointer of struct atm_vcc is set to atmtcp_control.vcc. The notable thing is struct atmtcp_control is uAPI but has a space for an in-kernel pointer. struct atmtcp_control { struct atmtcp_hdr hdr; /* must be first */ ... atm_kptr_t vcc; /* both directions */ ... } __ATM_API_ALIGN; typedef struct { unsigned char _[8]; } __ATM_API_ALIGN atm_kptr_t; The special message is processed in atmtcp_recv_control() called from atmtcp_c_send(). atmtcp_c_send() is vcc->dev->ops->send() and called from 2 paths: 1. .ndo_start_xmit() (vcc->send() == atm_send_aal0()) 2. vcc_sendmsg() The problem is sendmsg() does not validate the message length and userspace can abuse atmtcp_recv_control() to overwrite any kptr by atmtcp_control. Let's add a new ->pre_send() hook to validate messages from sendmsg(). [0]: Oops: general protection fault, probably for non-canonical address 0xdffffc00200000ab: 0000 [#1] SMP KASAN PTI KASAN: probably user-memory-access in range [0x0000000100000558-0x000000010000055f] CPU: 0 UID: 0 PID: 5865 Comm: syz-executor331 Not tainted 6.17.0-rc1-syzkaller-00215-gbab3ce404553 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 RIP: 0010:atmtcp_recv_control drivers/atm/atmtcp.c:93 [inline] RIP: 0010:atmtcp_c_send+0x1da/0x950 drivers/atm/atmtcp.c:297 Code: 4d 8d 75 1a 4c 89 f0 48 c1 e8 03 42 0f b6 04 20 84 c0 0f 85 15 06 00 00 41 0f b7 1e 4d 8d b7 60 05 00 00 4c 89 f0 48 c1 e8 03 <42> 0f b6 04 20 84 c0 0f 85 13 06 00 00 66 41 89 1e 4d 8d 75 1c 4c RSP: 0018:ffffc90003f5f810 EFLAGS: 00010203 RAX: 00000000200000ab RBX: 0000000000000000 RCX: 0000000000000000 RDX: ffff88802a510000 RSI: 00000000ffffffff RDI: ffff888030a6068c RBP: ffff88802699fb40 R08: ffff888030a606eb R09: 1ffff1100614c0dd R10: dffffc0000000000 R11: ffffffff8718fc40 R12: dffffc0000000000 R13: ffff888030a60680 R14: 000000010000055f R15: 00000000ffffffff FS: 00007f8d7e9236c0(0000) GS:ffff888125c1c000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000000045ad50 CR3: 0000000075bde000 CR4: 00000000003526f0 Call Trace: <TASK> vcc_sendmsg+0xa10/0xc60 net/atm/common.c:645 sock_sendmsg_nosec net/socket.c:714 [inline] __sock_sendmsg+0x219/0x270 net/socket.c:729 ____sys_sendmsg+0x505/0x830 net/socket.c:2614 ___sys_sendmsg+0x21f/0x2a0 net/socket.c:2668 __sys_sendmsg net/socket.c:2700 [inline] __do_sys_sendmsg net/socket.c:2705 [inline] __se_sys_sendmsg net/socket.c:2703 [inline] __x64_sys_sendmsg+0x19b/0x260 net/socket.c:2703 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f8d7e96a4a9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 51 18 00 00 90 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 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f8d7e923198 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f8d7e9f4308 RCX: 00007f8d7e96a4a9 RDX: 0000000000000000 RSI: 0000200000000240 RDI: 0000000000000005 RBP: 00007f8d7e9f4300 R08: 65732f636f72702f R09: 65732f636f72702f R10: 65732f636f72702f R11: 0000000000000246 R12: 00007f8d7e9c10ac R13: 00007f8d7e9231a0 R14: 0000200000000200 R15: 0000200000000250 </TASK> Modules linked in: Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Reported-by: syzbot+1741b56d54536f4ec349@syzkaller.appspotmail.com Closes: https://lore.kernel.org/netdev/68a6767c.050a0220.3d78fd.0011.GAE@google.com/ Tested-by: syzbot+1741b56d54536f4ec349@syzkaller.appspotmail.com Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com> Link: https://patch.msgid.link/20250821021901.2814721-1-kuniyu@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>

If preparing a write bio fails then blk_zone_wplug_bio_work() calls bio_endio() with zwplug->lock held. If a device mapper driver is stacked on top of the zoned block device then this results in nested locking of zwplug->lock. The resulting lockdep complaint is a false positive because this is nested locking and not recursive locking. Suppress this false positive by calling blk_zone_wplug_bio_io_error() without holding zwplug->lock. This is safe because no code in blk_zone_wplug_bio_io_error() depends on zwplug->lock being held. This patch suppresses the following lockdep complaint: WARNING: possible recursive locking detected -------------------------------------------- kworker/3:0H/46 is trying to acquire lock: ffffff882968b830 (&zwplug->lock){-...}-{2:2}, at: blk_zone_write_plug_bio_endio+0x64/0x1f0 but task is already holding lock: ffffff88315bc230 (&zwplug->lock){-...}-{2:2}, at: blk_zone_wplug_bio_work+0x8c/0x48c other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(&zwplug->lock); lock(&zwplug->lock); *** DEADLOCK *** May be due to missing lock nesting notation 3 locks held by kworker/3:0H/46: #0: ffffff8809486758 ((wq_completion)sdd_zwplugs){+.+.}-{0:0}, at: process_one_work+0x1bc/0x65c #1: ffffffc085de3d70 ((work_completion)(&zwplug->bio_work)){+.+.}-{0:0}, at: process_one_work+0x1e4/0x65c #2: ffffff88315bc230 (&zwplug->lock){-...}-{2:2}, at: blk_zone_wplug_bio_work+0x8c/0x48c stack backtrace: CPU: 3 UID: 0 PID: 46 Comm: kworker/3:0H Tainted: G W OE 6.12.38-android16-5-maybe-dirty-4k #1 8b362b6f76e3645a58cd27d86982bce10d150025 Tainted: [W]=WARN, [O]=OOT_MODULE, [E]=UNSIGNED_MODULE Hardware name: Spacecraft board based on MALIBU (DT) Workqueue: sdd_zwplugs blk_zone_wplug_bio_work Call trace: dump_backtrace+0xfc/0x17c show_stack+0x18/0x28 dump_stack_lvl+0x40/0xa0 dump_stack+0x18/0x24 print_deadlock_bug+0x38c/0x398 __lock_acquire+0x13e8/0x2e1c lock_acquire+0x134/0x2b4 _raw_spin_lock_irqsave+0x5c/0x80 blk_zone_write_plug_bio_endio+0x64/0x1f0 bio_endio+0x9c/0x240 __dm_io_complete+0x214/0x260 clone_endio+0xe8/0x214 bio_endio+0x218/0x240 blk_zone_wplug_bio_work+0x204/0x48c process_one_work+0x26c/0x65c worker_thread+0x33c/0x498 kthread+0x110/0x134 ret_from_fork+0x10/0x20 Cc: stable@vger.kernel.org Cc: Damien Le Moal <dlemoal@kernel.org> Cc: Christoph Hellwig <hch@lst.de> Fixes: dd291d7 ("block: Introduce zone write plugging") Signed-off-by: Bart Van Assche <bvanassche@acm.org> Reviewed-by: Damien Le Moal <dlemoal@kernel.org> Link: https://lore.kernel.org/r/20250825182720.1697203-1-bvanassche@acm.org Signed-off-by: Jens Axboe <axboe@kernel.dk>

into HEAD KVM/riscv fixes for 6.17, take #1 - Fix pte settings within kvm_riscv_gstage_ioremap() - Fix comments in kvm_riscv_check_vcpu_requests() - Fix stack overrun when setting vlenb via ONE_REG

commit c652887 ("KVM: arm64: vgic-v3: Allow userspace to write GICD_TYPER2.nASSGIcap") makes the allocation of vPEs depend on nASSGIcap for GICv4.1 hosts. While the vGIC v4 initialization and teardown is handled correctly, it erroneously attempts to establish a vLPI mapping to a VM that has no vPEs allocated: Unable to handle kernel NULL pointer dereference at virtual address 00000000000000a8 Mem abort info: ESR = 0x0000000096000044 EC = 0x25: DABT (current EL), IL = 32 bits SET = 0, FnV = 0 EA = 0, S1PTW = 0 FSC = 0x04: level 0 translation fault Data abort info: ISV = 0, ISS = 0x00000044, ISS2 = 0x00000000 CM = 0, WnR = 1, TnD = 0, TagAccess = 0 GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0 user pgtable: 4k pages, 48-bit VAs, pgdp=00000073a453b000 [00000000000000a8] pgd=0000000000000000, p4d=0000000000000000 Internal error: Oops: 0000000096000044 [#1] SMP pstate: 23400009 (nzCv daif +PAN -UAO +TCO +DIT -SSBS BTYPE=--) pc : its_irq_set_vcpu_affinity+0x58c/0x95c lr : its_irq_set_vcpu_affinity+0x1e0/0x95c sp : ffff8001029bb9e0 pmr_save: 00000060 x29: ffff8001029bba20 x28: ffff0001ca5e28c0 x27: 0000000000000000 x26: 0000000000000000 x25: ffff00019eee9f80 x24: ffff0001992b3f00 x23: ffff8001029bbab8 x22: ffff00001159fb80 x21: 00000000000024a7 x20: 00000000000024a7 x19: ffff00019eee9fb4 x18: 0000000000000494 x17: 000000000000000e x16: 0000000000000494 x15: 0000000000000002 x14: ffff0001a7f34600 x13: ffffccaad1203000 x12: 0000000000000018 x11: ffff000011991000 x10: 0000000000000000 x9 : 00000000000000a2 x8 : 00000000000020a8 x7 : 0000000000000000 x6 : 000000000000003f x5 : 0000000000000040 x4 : 0000000000000000 x3 : 0000000000000004 x2 : 0000000000000000 x1 : ffff8001029bbab8 x0 : 00000000000000a8 Call trace: its_irq_set_vcpu_affinity+0x58c/0x95c irq_set_vcpu_affinity+0x74/0xc8 its_map_vlpi+0x4c/0x94 kvm_vgic_v4_set_forwarding+0x134/0x298 kvm_arch_irq_bypass_add_producer+0x28/0x34 irq_bypass_register_producer+0xf8/0x1d8 vfio_msi_set_vector_signal+0x2c8/0x308 vfio_pci_set_msi_trigger+0x198/0x2d4 vfio_pci_set_irqs_ioctl+0xf0/0x104 vfio_pci_core_ioctl+0x6ac/0xc5c vfio_device_fops_unl_ioctl+0x128/0x370 __arm64_sys_ioctl+0x98/0xd0 el0_svc_common+0xd8/0x1d8 do_el0_svc+0x28/0x34 el0_svc+0x40/0xb8 el0t_64_sync_handler+0x70/0xbc el0t_64_sync+0x1a8/0x1ac Code: 321f0129 f940094a 8b08014 d1400900 (39000009) ---[ end trace 0000000000000000 ]--- Fix it by moving the GICv4.1 special-casing to vgic_supports_direct_msis(), returning false if the user explicitly disabled nASSGIcap for the VM. Fixes: c652887 ("KVM: arm64: vgic-v3: Allow userspace to write GICD_TYPER2.nASSGIcap") Suggested-by: Oliver Upton <oliver.upton@linux.dev> Signed-off-by: Raghavendra Rao Ananta <rananta@google.com> Link: https://lore.kernel.org/r/20250729210644.830364-1-rananta@google.com Signed-off-by: Oliver Upton <oliver.upton@linux.dev>

In gicv5_irs_of_init_affinity() a WARN_ON() is triggered if: 1) a phandle in the "cpus" property does not correspond to a valid OF node 2 a CPU logical id does not exist for a given OF cpu_node #1 is a firmware bug and should be reported as such but does not warrant a WARN_ON() backtrace. #2 is not necessarily an error condition (eg a kernel can be booted with nr_cpus=X limiting the number of cores artificially) and therefore there is no reason to clutter the kernel log with WARN_ON() output when the condition is hit. Rework the IRS affinity parsing code to remove undue WARN_ON()s thus making it less noisy. Signed-off-by: Lorenzo Pieralisi <lpieralisi@kernel.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/all/20250814094138.1611017-1-lpieralisi@kernel.org

When there are memory-only nodes (nodes without CPUs), these nodes are not properly initialized, causing kernel panic during boot. of_numa_init of_numa_parse_cpu_nodes node_set(nid, numa_nodes_parsed); of_numa_parse_memory_nodes In of_numa_parse_cpu_nodes, numa_nodes_parsed gets updated only for nodes containing CPUs. Memory-only nodes should have been updated in of_numa_parse_memory_nodes, but they weren't. Subsequently, when free_area_init() attempts to access NODE_DATA() for these uninitialized memory nodes, the kernel panics due to NULL pointer dereference. This can be reproduced on ARM64 QEMU with 1 CPU and 2 memory nodes: qemu-system-aarch64 \ -cpu host -nographic \ -m 4G -smp 1 \ -machine virt,accel=kvm,gic-version=3,iommu=smmuv3 \ -object memory-backend-ram,size=2G,id=mem0 \ -object memory-backend-ram,size=2G,id=mem1 \ -numa node,nodeid=0,memdev=mem0 \ -numa node,nodeid=1,memdev=mem1 \ -kernel $IMAGE \ -hda $DISK \ -append "console=ttyAMA0 root=/dev/vda rw earlycon" [ 0.000000] Booting Linux on physical CPU 0x0000000000 [0x481fd010] [ 0.000000] Linux version 6.17.0-rc1-00001-gabb4b3daf18c-dirty (yintirui@local) (gcc (GCC) 12.3.1, GNU ld (GNU Binutils) 2.41) #52 SMP PREEMPT Mon Aug 18 09:49:40 CST 2025 [ 0.000000] KASLR enabled [ 0.000000] random: crng init done [ 0.000000] Machine model: linux,dummy-virt [ 0.000000] efi: UEFI not found. [ 0.000000] earlycon: pl11 at MMIO 0x0000000009000000 (options '') [ 0.000000] printk: legacy bootconsole [pl11] enabled [ 0.000000] OF: reserved mem: Reserved memory: No reserved-memory node in the DT [ 0.000000] NODE_DATA(0) allocated [mem 0xbfffd9c0-0xbfffffff] [ 0.000000] node 1 must be removed before remove section 23 [ 0.000000] Zone ranges: [ 0.000000] DMA [mem 0x0000000040000000-0x00000000ffffffff] [ 0.000000] DMA32 empty [ 0.000000] Normal [mem 0x0000000100000000-0x000000013fffffff] [ 0.000000] Movable zone start for each node [ 0.000000] Early memory node ranges [ 0.000000] node 0: [mem 0x0000000040000000-0x00000000bfffffff] [ 0.000000] node 1: [mem 0x00000000c0000000-0x000000013fffffff] [ 0.000000] Initmem setup node 0 [mem 0x0000000040000000-0x00000000bfffffff] [ 0.000000] Unable to handle kernel NULL pointer dereference at virtual address 00000000000000a0 [ 0.000000] Mem abort info: [ 0.000000] ESR = 0x0000000096000004 [ 0.000000] EC = 0x25: DABT (current EL), IL = 32 bits [ 0.000000] SET = 0, FnV = 0 [ 0.000000] EA = 0, S1PTW = 0 [ 0.000000] FSC = 0x04: level 0 translation fault [ 0.000000] Data abort info: [ 0.000000] ISV = 0, ISS = 0x00000004, ISS2 = 0x00000000 [ 0.000000] CM = 0, WnR = 0, TnD = 0, TagAccess = 0 [ 0.000000] GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0 [ 0.000000] [00000000000000a0] user address but active_mm is swapper [ 0.000000] Internal error: Oops: 0000000096000004 [#1] SMP [ 0.000000] Modules linked in: [ 0.000000] CPU: 0 UID: 0 PID: 0 Comm: swapper Not tainted 6.17.0-rc1-00001-g760c6dabf762-dirty #54 PREEMPT [ 0.000000] Hardware name: linux,dummy-virt (DT) [ 0.000000] pstate: 800000c5 (Nzcv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--) [ 0.000000] pc : free_area_init+0x50c/0xf9c [ 0.000000] lr : free_area_init+0x5c0/0xf9c [ 0.000000] sp : ffffa02ca0f33c00 [ 0.000000] x29: ffffa02ca0f33cb0 x28: 0000000000000000 x27: 0000000000000000 [ 0.000000] x26: 4ec4ec4ec4ec4ec5 x25: 00000000000c0000 x24: 00000000000c0000 [ 0.000000] x23: 0000000000040000 x22: 0000000000000000 x21: ffffa02ca0f3b368 [ 0.000000] x20: ffffa02ca14c7b98 x19: 0000000000000000 x18: 0000000000000002 [ 0.000000] x17: 000000000000cacc x16: 0000000000000001 x15: 0000000000000001 [ 0.000000] x14: 0000000080000000 x13: 0000000000000018 x12: 0000000000000002 [ 0.000000] x11: ffffa02ca0fd4f00 x10: ffffa02ca14bab20 x9 : ffffa02ca14bab38 [ 0.000000] x8 : 00000000000c0000 x7 : 0000000000000001 x6 : 0000000000000002 [ 0.000000] x5 : 0000000140000000 x4 : ffffa02ca0f33c90 x3 : ffffa02ca0f33ca0 [ 0.000000] x2 : ffffa02ca0f33c98 x1 : 0000000080000000 x0 : 0000000000000001 [ 0.000000] Call trace: [ 0.000000] free_area_init+0x50c/0xf9c (P) [ 0.000000] bootmem_init+0x110/0x1dc [ 0.000000] setup_arch+0x278/0x60c [ 0.000000] start_kernel+0x70/0x748 [ 0.000000] __primary_switched+0x88/0x90 [ 0.000000] Code: d503201f b98093e0 52800016 f8607a93 (f9405260) [ 0.000000] ---[ end trace 0000000000000000 ]--- [ 0.000000] Kernel panic - not syncing: Attempted to kill the idle task! [ 0.000000] ---[ end Kernel panic - not syncing: Attempted to kill the idle task! ]--- Link: https://lkml.kernel.org/r/20250819075510.2079961-1-yintirui@huawei.com Fixes: 7675076 ("arch_numa: switch over to numa_memblks") Signed-off-by: Yin Tirui <yintirui@huawei.com> Acked-by: David Hildenbrand <david@redhat.com> Acked-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Reviewed-by: Kefeng Wang <wangkefeng.wang@huawei.com> Cc: Chen Jun <chenjun102@huawei.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Joanthan Cameron <Jonathan.Cameron@huawei.com> Cc: Rob Herring <robh@kernel.org> Cc: Saravana Kannan <saravanak@google.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

While working on the lazy MMU mode enablement for s390 I hit pretty curious issues in the kasan code. The first is related to a custom kasan-based sanitizer aimed at catching invalid accesses to PTEs and is inspired by [1] conversation. The kasan complains on valid PTE accesses, while the shadow memory is reported as unpoisoned: [ 102.783993] ================================================================== [ 102.784008] BUG: KASAN: out-of-bounds in set_pte_range+0x36c/0x390 [ 102.784016] Read of size 8 at addr 0000780084cf9608 by task vmalloc_test/0/5542 [ 102.784019] [ 102.784040] CPU: 1 UID: 0 PID: 5542 Comm: vmalloc_test/0 Kdump: loaded Tainted: G OE 6.16.0-gcc-ipte-kasan-11657-gb2d930c4950e #340 PREEMPT [ 102.784047] Tainted: [O]=OOT_MODULE, [E]=UNSIGNED_MODULE [ 102.784049] Hardware name: IBM 8561 T01 703 (LPAR) [ 102.784052] Call Trace: [ 102.784054] [<00007fffe0147ac0>] dump_stack_lvl+0xe8/0x140 [ 102.784059] [<00007fffe0112484>] print_address_description.constprop.0+0x34/0x2d0 [ 102.784066] [<00007fffe011282c>] print_report+0x10c/0x1f8 [ 102.784071] [<00007fffe090785a>] kasan_report+0xfa/0x220 [ 102.784078] [<00007fffe01d3dec>] set_pte_range+0x36c/0x390 [ 102.784083] [<00007fffe01d41c2>] leave_ipte_batch+0x3b2/0xb10 [ 102.784088] [<00007fffe07d3650>] apply_to_pte_range+0x2f0/0x4e0 [ 102.784094] [<00007fffe07e62e4>] apply_to_pmd_range+0x194/0x3e0 [ 102.784099] [<00007fffe07e820e>] __apply_to_page_range+0x2fe/0x7a0 [ 102.784104] [<00007fffe07e86d8>] apply_to_page_range+0x28/0x40 [ 102.784109] [<00007fffe090a3ec>] __kasan_populate_vmalloc+0xec/0x310 [ 102.784114] [<00007fffe090aa36>] kasan_populate_vmalloc+0x96/0x130 [ 102.784118] [<00007fffe0833a04>] alloc_vmap_area+0x3d4/0xf30 [ 102.784123] [<00007fffe083a8ba>] __get_vm_area_node+0x1aa/0x4c0 [ 102.784127] [<00007fffe083c4f6>] __vmalloc_node_range_noprof+0x126/0x4e0 [ 102.784131] [<00007fffe083c980>] __vmalloc_node_noprof+0xd0/0x110 [ 102.784135] [<00007fffe083ca32>] vmalloc_noprof+0x32/0x40 [ 102.784139] [<00007fff608aa336>] fix_size_alloc_test+0x66/0x150 [test_vmalloc] [ 102.784147] [<00007fff608aa710>] test_func+0x2f0/0x430 [test_vmalloc] [ 102.784153] [<00007fffe02841f8>] kthread+0x3f8/0x7a0 [ 102.784159] [<00007fffe014d8b4>] __ret_from_fork+0xd4/0x7d0 [ 102.784164] [<00007fffe299c00a>] ret_from_fork+0xa/0x30 [ 102.784173] no locks held by vmalloc_test/0/5542. [ 102.784176] [ 102.784178] The buggy address belongs to the physical page: [ 102.784186] page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x84cf9 [ 102.784198] flags: 0x3ffff00000000000(node=0|zone=1|lastcpupid=0x1ffff) [ 102.784212] page_type: f2(table) [ 102.784225] raw: 3ffff00000000000 0000000000000000 0000000000000122 0000000000000000 [ 102.784234] raw: 0000000000000000 0000000000000000 f200000000000001 0000000000000000 [ 102.784248] page dumped because: kasan: bad access detected [ 102.784250] [ 102.784252] Memory state around the buggy address: [ 102.784260] 0000780084cf9500: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 102.784274] 0000780084cf9580: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 102.784277] >0000780084cf9600: fd 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 102.784290] ^ [ 102.784293] 0000780084cf9680: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 102.784303] 0000780084cf9700: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 102.784306] ================================================================== The second issue hits when the custom sanitizer above is not implemented, but the kasan itself is still active: [ 1554.438028] Unable to handle kernel pointer dereference in virtual kernel address space [ 1554.438065] Failing address: 001c0ff0066f0000 TEID: 001c0ff0066f0403 [ 1554.438076] Fault in home space mode while using kernel ASCE. [ 1554.438103] AS:00000000059d400b R2:0000000ffec5c00b R3:00000000c6c9c007 S:0000000314470001 P:00000000d0ab413d [ 1554.438158] Oops: 0011 ilc:2 [#1]SMP [ 1554.438175] Modules linked in: test_vmalloc(E+) nft_fib_inet(E) nft_fib_ipv4(E) nft_fib_ipv6(E) nft_fib(E) nft_reject_inet(E) nf_reject_ipv4(E) nf_reject_ipv6(E) nft_reject(E) nft_ct(E) nft_chain_nat(E) nf_nat(E) nf_conntrack(E) nf_defrag_ipv6(E) nf_defrag_ipv4(E) nf_tables(E) sunrpc(E) pkey_pckmo(E) uvdevice(E) s390_trng(E) rng_core(E) eadm_sch(E) vfio_ccw(E) mdev(E) vfio_iommu_type1(E) vfio(E) sch_fq_codel(E) drm(E) loop(E) i2c_core(E) drm_panel_orientation_quirks(E) nfnetlink(E) ctcm(E) fsm(E) zfcp(E) scsi_transport_fc(E) diag288_wdt(E) watchdog(E) ghash_s390(E) prng(E) aes_s390(E) des_s390(E) libdes(E) sha3_512_s390(E) sha3_256_s390(E) sha512_s390(E) sha1_s390(E) sha_common(E) pkey(E) autofs4(E) [ 1554.438319] Unloaded tainted modules: pkey_uv(E):1 hmac_s390(E):2 [ 1554.438354] CPU: 1 UID: 0 PID: 1715 Comm: vmalloc_test/0 Kdump: loaded Tainted: G E 6.16.0-gcc-ipte-kasan-11657-gb2d930c4950e #350 PREEMPT [ 1554.438368] Tainted: [E]=UNSIGNED_MODULE [ 1554.438374] Hardware name: IBM 8561 T01 703 (LPAR) [ 1554.438381] Krnl PSW : 0704e00180000000 00007fffe1d3d6ae (memset+0x5e/0x98) [ 1554.438396] R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:0 AS:3 CC:2 PM:0 RI:0 EA:3 [ 1554.438409] Krnl GPRS: 0000000000000001 001c0ff0066f0000 001c0ff0066f0000 00000000000000f8 [ 1554.438418] 00000000000009fe 0000000000000009 0000000000000000 0000000000000002 [ 1554.438426] 0000000000005000 000078031ae655c8 00000feffdcf9f59 0000780258672a20 [ 1554.438433] 0000780243153500 00007f8033780000 00007fffe083a510 00007f7fee7cfa00 [ 1554.438452] Krnl Code: 00007fffe1d3d6a0: eb540008000c srlg %r5,%r4,8 00007fffe1d3d6a6: b9020055 ltgr %r5,%r5 #00007fffe1d3d6aa: a784000b brc 8,00007fffe1d3d6c0 >00007fffe1d3d6ae: 42301000 stc %r3,0(%r1) 00007fffe1d3d6b2: d2fe10011000 mvc 1(255,%r1),0(%r1) 00007fffe1d3d6b8: 41101100 la %r1,256(%r1) 00007fffe1d3d6bc: a757fff9 brctg %r5,00007fffe1d3d6ae 00007fffe1d3d6c0: 42301000 stc %r3,0(%r1) [ 1554.438539] Call Trace: [ 1554.438545] [<00007fffe1d3d6ae>] memset+0x5e/0x98 [ 1554.438552] ([<00007fffe083a510>] remove_vm_area+0x220/0x400) [ 1554.438562] [<00007fffe083a9d6>] vfree.part.0+0x26/0x810 [ 1554.438569] [<00007fff6073bd50>] fix_align_alloc_test+0x50/0x90 [test_vmalloc] [ 1554.438583] [<00007fff6073c73a>] test_func+0x46a/0x6c0 [test_vmalloc] [ 1554.438593] [<00007fffe0283ac8>] kthread+0x3f8/0x7a0 [ 1554.438603] [<00007fffe014d8b4>] __ret_from_fork+0xd4/0x7d0 [ 1554.438613] [<00007fffe299ac0a>] ret_from_fork+0xa/0x30 [ 1554.438622] INFO: lockdep is turned off. [ 1554.438627] Last Breaking-Event-Address: [ 1554.438632] [<00007fffe1d3d65c>] memset+0xc/0x98 [ 1554.438644] Kernel panic - not syncing: Fatal exception: panic_on_oops This series fixes the above issues and is a pre-requisite for the s390 lazy MMU mode implementation. test_vmalloc was used to stress-test the fixes. This patch (of 2): When vmalloc shadow memory is established the modification of the corresponding page tables is not protected by any locks. Instead, the locking is done per-PTE. This scheme however has defects. kasan_populate_vmalloc_pte() - while ptep_get() read is atomic the sequence pte_none(ptep_get()) is not. Doing that outside of the lock might lead to a concurrent PTE update and what could be seen as a shadow memory corruption as result. kasan_depopulate_vmalloc_pte() - by the time a page whose address was extracted from ptep_get() read and cached in a local variable outside of the lock is attempted to get free, could actually be freed already. To avoid these put ptep_get() itself and the code that manipulates the result of the read under lock. In addition, move freeing of the page out of the atomic context. Link: https://lkml.kernel.org/r/cover.1755528662.git.agordeev@linux.ibm.com Link: https://lkml.kernel.org/r/adb258634194593db294c0d1fb35646e894d6ead.1755528662.git.agordeev@linux.ibm.com Link: https://lore.kernel.org/linux-mm/5b0609c9-95ee-4e48-bb6d-98f57c5d2c31@arm.com/ [1] Fixes: 3c5c3cf ("kasan: support backing vmalloc space with real shadow memory") Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com> Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com> Cc: Daniel Axtens <dja@axtens.net> Cc: Marc Rutland <mark.rutland@arm.com> Cc: Ryan Roberts <ryan.roberts@arm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

During our internal testing, we started observing intermittent boot failures when the machine uses 4-level paging and has a large amount of persistent memory: BUG: unable to handle page fault for address: ffffe70000000034 #PF: supervisor write access in kernel mode #PF: error_code(0x0002) - not-present page PGD 0 P4D 0 Oops: 0002 [#1] SMP NOPTI RIP: 0010:__init_single_page+0x9/0x6d Call Trace: <TASK> __init_zone_device_page+0x17/0x5d memmap_init_zone_device+0x154/0x1bb pagemap_range+0x2e0/0x40f memremap_pages+0x10b/0x2f0 devm_memremap_pages+0x1e/0x60 dev_dax_probe+0xce/0x2ec [device_dax] dax_bus_probe+0x6d/0xc9 [... snip ...] </TASK> It turns out that the kernel panics while initializing vmemmap (struct page array) when the vmemmap region spans two PGD entries, because the new PGD entry is only installed in init_mm.pgd, but not in the page tables of other tasks. And looking at __populate_section_memmap(): if (vmemmap_can_optimize(altmap, pgmap)) // does not sync top level page tables r = vmemmap_populate_compound_pages(pfn, start, end, nid, pgmap); else // sync top level page tables in x86 r = vmemmap_populate(start, end, nid, altmap); In the normal path, vmemmap_populate() in arch/x86/mm/init_64.c synchronizes the top level page table (See commit 9b86152 ("x86-64, mem: Update all PGDs for direct mapping and vmemmap mapping changes")) so that all tasks in the system can see the new vmemmap area. However, when vmemmap_can_optimize() returns true, the optimized path skips synchronization of top-level page tables. This is because vmemmap_populate_compound_pages() is implemented in core MM code, which does not handle synchronization of the top-level page tables. Instead, the core MM has historically relied on each architecture to perform this synchronization manually. We're not the first party to encounter a crash caused by not-sync'd top level page tables: earlier this year, Gwan-gyeong Mun attempted to address the issue [1] [2] after hitting a kernel panic when x86 code accessed the vmemmap area before the corresponding top-level entries were synced. At that time, the issue was believed to be triggered only when struct page was enlarged for debugging purposes, and the patch did not get further updates. It turns out that current approach of relying on each arch to handle the page table sync manually is fragile because 1) it's easy to forget to sync the top level page table, and 2) it's also easy to overlook that the kernel should not access the vmemmap and direct mapping areas before the sync. # The solution: Make page table sync more code robust and harder to miss To address this, Dave Hansen suggested [3] [4] introducing {pgd,p4d}_populate_kernel() for updating kernel portion of the page tables and allow each architecture to explicitly perform synchronization when installing top-level entries. With this approach, we no longer need to worry about missing the sync step, reducing the risk of future regressions. The new interface reuses existing ARCH_PAGE_TABLE_SYNC_MASK, PGTBL_P*D_MODIFIED and arch_sync_kernel_mappings() facility used by vmalloc and ioremap to synchronize page tables. pgd_populate_kernel() looks like this: static inline void pgd_populate_kernel(unsigned long addr, pgd_t *pgd, p4d_t *p4d) { pgd_populate(&init_mm, pgd, p4d); if (ARCH_PAGE_TABLE_SYNC_MASK & PGTBL_PGD_MODIFIED) arch_sync_kernel_mappings(addr, addr); } It is worth noting that vmalloc() and apply_to_range() carefully synchronizes page tables by calling p*d_alloc_track() and arch_sync_kernel_mappings(), and thus they are not affected by this patch series. This series was hugely inspired by Dave Hansen's suggestion and hence added Suggested-by: Dave Hansen. Cc stable because lack of this series opens the door to intermittent boot failures. This patch (of 3): Move ARCH_PAGE_TABLE_SYNC_MASK and arch_sync_kernel_mappings() to linux/pgtable.h so that they can be used outside of vmalloc and ioremap. Link: https://lkml.kernel.org/r/20250818020206.4517-1-harry.yoo@oracle.com Link: https://lkml.kernel.org/r/20250818020206.4517-2-harry.yoo@oracle.com Link: https://lore.kernel.org/linux-mm/20250220064105.808339-1-gwan-gyeong.mun@intel.com [1] Link: https://lore.kernel.org/linux-mm/20250311114420.240341-1-gwan-gyeong.mun@intel.com [2] Link: https://lore.kernel.org/linux-mm/d1da214c-53d3-45ac-a8b6-51821c5416e4@intel.com [3] Link: https://lore.kernel.org/linux-mm/4d800744-7b88-41aa-9979-b245e8bf794b@intel.com [4] Fixes: 8d40091 ("x86/vmemmap: handle unpopulated sub-pmd ranges") Signed-off-by: Harry Yoo <harry.yoo@oracle.com> Acked-by: Kiryl Shutsemau <kas@kernel.org> Reviewed-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Reviewed-by: "Uladzislau Rezki (Sony)" <urezki@gmail.com> Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Acked-by: David Hildenbrand <david@redhat.com> Cc: Alexander Potapenko <glider@google.com> Cc: Alistair Popple <apopple@nvidia.com> Cc: Andrey Konovalov <andreyknvl@gmail.com> Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com> Cc: Anshuman Khandual <anshuman.khandual@arm.com> Cc: Ard Biesheuvel <ardb@kernel.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: bibo mao <maobibo@loongson.cn> Cc: Borislav Betkov <bp@alien8.de> Cc: Christoph Lameter (Ampere) <cl@gentwo.org> Cc: Dennis Zhou <dennis@kernel.org> Cc: Dev Jain <dev.jain@arm.com> Cc: Dmitriy Vyukov <dvyukov@google.com> Cc: Gwan-gyeong Mun <gwan-gyeong.mun@intel.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jane Chu <jane.chu@oracle.com> Cc: Joao Martins <joao.m.martins@oracle.com> Cc: Joerg Roedel <joro@8bytes.org> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Kevin Brodsky <kevin.brodsky@arm.com> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Oscar Salvador <osalvador@suse.de> Cc: Peter Xu <peterx@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Qi Zheng <zhengqi.arch@bytedance.com> Cc: Ryan Roberts <ryan.roberts@arm.com> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Tejun Heo <tj@kernel.org> Cc: Thomas Gleinxer <tglx@linutronix.de> Cc: Thomas Huth <thuth@redhat.com> Cc: Vincenzo Frascino <vincenzo.frascino@arm.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

…ings() Define ARCH_PAGE_TABLE_SYNC_MASK and arch_sync_kernel_mappings() to ensure page tables are properly synchronized when calling p*d_populate_kernel(). For 5-level paging, synchronization is performed via pgd_populate_kernel(). In 4-level paging, pgd_populate() is a no-op, so synchronization is instead performed at the P4D level via p4d_populate_kernel(). This fixes intermittent boot failures on systems using 4-level paging and a large amount of persistent memory: BUG: unable to handle page fault for address: ffffe70000000034 #PF: supervisor write access in kernel mode #PF: error_code(0x0002) - not-present page PGD 0 P4D 0 Oops: 0002 [#1] SMP NOPTI RIP: 0010:__init_single_page+0x9/0x6d Call Trace: <TASK> __init_zone_device_page+0x17/0x5d memmap_init_zone_device+0x154/0x1bb pagemap_range+0x2e0/0x40f memremap_pages+0x10b/0x2f0 devm_memremap_pages+0x1e/0x60 dev_dax_probe+0xce/0x2ec [device_dax] dax_bus_probe+0x6d/0xc9 [... snip ...] </TASK> It also fixes a crash in vmemmap_set_pmd() caused by accessing vmemmap before sync_global_pgds() [1]: BUG: unable to handle page fault for address: ffffeb3ff1200000 #PF: supervisor write access in kernel mode #PF: error_code(0x0002) - not-present page PGD 0 P4D 0 Oops: Oops: 0002 [#1] PREEMPT SMP NOPTI Tainted: [W]=WARN RIP: 0010:vmemmap_set_pmd+0xff/0x230 <TASK> vmemmap_populate_hugepages+0x176/0x180 vmemmap_populate+0x34/0x80 __populate_section_memmap+0x41/0x90 sparse_add_section+0x121/0x3e0 __add_pages+0xba/0x150 add_pages+0x1d/0x70 memremap_pages+0x3dc/0x810 devm_memremap_pages+0x1c/0x60 xe_devm_add+0x8b/0x100 [xe] xe_tile_init_noalloc+0x6a/0x70 [xe] xe_device_probe+0x48c/0x740 [xe] [... snip ...] Link: https://lkml.kernel.org/r/20250818020206.4517-4-harry.yoo@oracle.com Fixes: 8d40091 ("x86/vmemmap: handle unpopulated sub-pmd ranges") Signed-off-by: Harry Yoo <harry.yoo@oracle.com> Closes: https://lore.kernel.org/linux-mm/20250311114420.240341-1-gwan-gyeong.mun@intel.com [1] Suggested-by: Dave Hansen <dave.hansen@linux.intel.com> Acked-by: Kiryl Shutsemau <kas@kernel.org> Reviewed-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Acked-by: David Hildenbrand <david@redhat.com> Cc: Alexander Potapenko <glider@google.com> Cc: Alistair Popple <apopple@nvidia.com> Cc: Andrey Konovalov <andreyknvl@gmail.com> Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com> Cc: Anshuman Khandual <anshuman.khandual@arm.com> Cc: Ard Biesheuvel <ardb@kernel.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: bibo mao <maobibo@loongson.cn> Cc: Borislav Betkov <bp@alien8.de> Cc: Christoph Lameter (Ampere) <cl@gentwo.org> Cc: Dennis Zhou <dennis@kernel.org> Cc: Dev Jain <dev.jain@arm.com> Cc: Dmitriy Vyukov <dvyukov@google.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jane Chu <jane.chu@oracle.com> Cc: Joao Martins <joao.m.martins@oracle.com> Cc: Joerg Roedel <joro@8bytes.org> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Kevin Brodsky <kevin.brodsky@arm.com> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Oscar Salvador <osalvador@suse.de> Cc: Peter Xu <peterx@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Qi Zheng <zhengqi.arch@bytedance.com> Cc: Ryan Roberts <ryan.roberts@arm.com> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Tejun Heo <tj@kernel.org> Cc: Thomas Gleinxer <tglx@linutronix.de> Cc: Thomas Huth <thuth@redhat.com> Cc: "Uladzislau Rezki (Sony)" <urezki@gmail.com> Cc: Vincenzo Frascino <vincenzo.frascino@arm.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

sched_numa_find_nth_cpu() uses a bsearch to look for the 'closest' CPU in sched_domains_numa_masks and given cpus mask. However they might not intersect if all CPUs in the cpus mask are offline. bsearch will return NULL in that case, bail out instead of dereferencing a bogus pointer. The previous behaviour lead to this bug when using maxcpus=4 on an rk3399 (LLLLbb) (i.e. booting with all big CPUs offline): [ 1.422922] Unable to handle kernel paging request at virtual address ffffff8000000000 [ 1.423635] Mem abort info: [ 1.423889] ESR = 0x0000000096000006 [ 1.424227] EC = 0x25: DABT (current EL), IL = 32 bits [ 1.424715] SET = 0, FnV = 0 [ 1.424995] EA = 0, S1PTW = 0 [ 1.425279] FSC = 0x06: level 2 translation fault [ 1.425735] Data abort info: [ 1.425998] ISV = 0, ISS = 0x00000006, ISS2 = 0x00000000 [ 1.426499] CM = 0, WnR = 0, TnD = 0, TagAccess = 0 [ 1.426952] GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0 [ 1.427428] swapper pgtable: 4k pages, 39-bit VAs, pgdp=0000000004a9f000 [ 1.428038] [ffffff8000000000] pgd=18000000f7fff403, p4d=18000000f7fff403, pud=18000000f7fff403, pmd=0000000000000000 [ 1.429014] Internal error: Oops: 0000000096000006 [#1] SMP [ 1.429525] Modules linked in: [ 1.429813] CPU: 3 UID: 0 PID: 1 Comm: swapper/0 Not tainted 6.17.0-rc4-dirty #343 PREEMPT [ 1.430559] Hardware name: Pine64 RockPro64 v2.1 (DT) [ 1.431012] pstate: 60000005 (nZCv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--) [ 1.431634] pc : sched_numa_find_nth_cpu+0x2a0/0x488 [ 1.432094] lr : sched_numa_find_nth_cpu+0x284/0x488 [ 1.432543] sp : ffffffc084e1b960 [ 1.432843] x29: ffffffc084e1b960 x28: ffffff80078a8800 x27: ffffffc0846eb1d0 [ 1.433495] x26: 0000000000000000 x25: 0000000000000000 x24: 0000000000000000 [ 1.434144] x23: 0000000000000000 x22: fffffffffff7f093 x21: ffffffc081de6378 [ 1.434792] x20: 0000000000000000 x19: 0000000ffff7f093 x18: 00000000ffffffff [ 1.435441] x17: 3030303866666666 x16: 66663d736b73616d x15: ffffffc104e1b5b7 [ 1.436091] x14: 0000000000000000 x13: ffffffc084712860 x12: 0000000000000372 [ 1.436739] x11: 0000000000000126 x10: ffffffc08476a860 x9 : ffffffc084712860 [ 1.437389] x8 : 00000000ffffefff x7 : ffffffc08476a860 x6 : 0000000000000000 [ 1.438036] x5 : 000000000000bff4 x4 : 0000000000000000 x3 : 0000000000000000 [ 1.438683] x2 : 0000000000000000 x1 : ffffffc0846eb000 x0 : ffffff8000407b68 [ 1.439332] Call trace: [ 1.439559] sched_numa_find_nth_cpu+0x2a0/0x488 (P) [ 1.440016] smp_call_function_any+0xc8/0xd0 [ 1.440416] armv8_pmu_init+0x58/0x27c [ 1.440770] armv8_cortex_a72_pmu_init+0x20/0x2c [ 1.441199] arm_pmu_device_probe+0x1e4/0x5e8 [ 1.441603] armv8_pmu_device_probe+0x1c/0x28 [ 1.442007] platform_probe+0x5c/0xac [ 1.442347] really_probe+0xbc/0x298 [ 1.442683] __driver_probe_device+0x78/0x12c [ 1.443087] driver_probe_device+0xdc/0x160 [ 1.443475] __driver_attach+0x94/0x19c [ 1.443833] bus_for_each_dev+0x74/0xd4 [ 1.444190] driver_attach+0x24/0x30 [ 1.444525] bus_add_driver+0xe4/0x208 [ 1.444874] driver_register+0x60/0x128 [ 1.445233] __platform_driver_register+0x24/0x30 [ 1.445662] armv8_pmu_driver_init+0x28/0x4c [ 1.446059] do_one_initcall+0x44/0x25c [ 1.446416] kernel_init_freeable+0x1dc/0x3bc [ 1.446820] kernel_init+0x20/0x1d8 [ 1.447151] ret_from_fork+0x10/0x20 [ 1.447493] Code: 90022e21 f000e5f5 910de2b5 2a1703e2 (f8767803) [ 1.448040] ---[ end trace 0000000000000000 ]--- [ 1.448483] note: swapper/0[1] exited with preempt_count 1 [ 1.449047] Kernel panic - not syncing: Attempted to kill init! exitcode=0x0000000b [ 1.449741] SMP: stopping secondary CPUs [ 1.450105] Kernel Offset: disabled [ 1.450419] CPU features: 0x000000,00080000,20002001,0400421b [ 1.450935] Memory Limit: none [ 1.451217] ---[ end Kernel panic - not syncing: Attempted to kill init! exitcode=0x0000000b ]--- Yury: with the fix, the function returns cpu == nr_cpu_ids, and later in smp_call_function_any -> smp_call_function_single -> generic_exec_single we test the cpu for '>= nr_cpu_ids' and return -ENXIO. So everything is handled correctly. Fixes: cd7f553 ("sched: add sched_numa_find_nth_cpu()") Cc: stable@vger.kernel.org Signed-off-by: Christian Loehle <christian.loehle@arm.com> Signed-off-by: Yury Norov (NVIDIA) <yury.norov@gmail.com>

tee_shm_put have NULL pointer dereference: __optee_disable_shm_cache --> shm = reg_pair_to_ptr(...);//shm maybe return NULL tee_shm_free(shm); --> tee_shm_put(shm);//crash Add check in tee_shm_put to fix it. panic log: Unable to handle kernel paging request at virtual address 0000000000100cca Mem abort info: ESR = 0x0000000096000004 EC = 0x25: DABT (current EL), IL = 32 bits SET = 0, FnV = 0 EA = 0, S1PTW = 0 FSC = 0x04: level 0 translation fault Data abort info: ISV = 0, ISS = 0x00000004, ISS2 = 0x00000000 CM = 0, WnR = 0, TnD = 0, TagAccess = 0 GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0 user pgtable: 4k pages, 48-bit VAs, pgdp=0000002049d07000 [0000000000100cca] pgd=0000000000000000, p4d=0000000000000000 Internal error: Oops: 0000000096000004 [#1] SMP CPU: 2 PID: 14442 Comm: systemd-sleep Tainted: P OE ------- ---- 6.6.0-39-generic #38 Source Version: 938b255f6cb8817c95b0dd5c8c2944acfce94b07 Hardware name: greatwall GW-001Y1A-FTH, BIOS Great Wall BIOS V3.0 10/26/2022 pstate: 80000005 (Nzcv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : tee_shm_put+0x24/0x188 lr : tee_shm_free+0x14/0x28 sp : ffff001f98f9faf0 x29: ffff001f98f9faf0 x28: ffff0020df543cc0 x27: 0000000000000000 x26: ffff001f811344a0 x25: ffff8000818dac00 x24: ffff800082d8d048 x23: ffff001f850fcd18 x22: 0000000000000001 x21: ffff001f98f9fb88 x20: ffff001f83e76218 x19: ffff001f83e761e0 x18: 000000000000ffff x17: 303a30303a303030 x16: 0000000000000000 x15: 0000000000000003 x14: 0000000000000001 x13: 0000000000000000 x12: 0101010101010101 x11: 0000000000000001 x10: 0000000000000001 x9 : ffff800080e08d0c x8 : ffff001f98f9fb88 x7 : 0000000000000000 x6 : 0000000000000000 x5 : 0000000000000000 x4 : 0000000000000000 x3 : 0000000000000000 x2 : ffff001f83e761e0 x1 : 00000000ffff001f x0 : 0000000000100cca Call trace: tee_shm_put+0x24/0x188 tee_shm_free+0x14/0x28 __optee_disable_shm_cache+0xa8/0x108 optee_shutdown+0x28/0x38 platform_shutdown+0x28/0x40 device_shutdown+0x144/0x2b0 kernel_power_off+0x3c/0x80 hibernate+0x35c/0x388 state_store+0x64/0x80 kobj_attr_store+0x14/0x28 sysfs_kf_write+0x48/0x60 kernfs_fop_write_iter+0x128/0x1c0 vfs_write+0x270/0x370 ksys_write+0x6c/0x100 __arm64_sys_write+0x20/0x30 invoke_syscall+0x4c/0x120 el0_svc_common.constprop.0+0x44/0xf0 do_el0_svc+0x24/0x38 el0_svc+0x24/0x88 el0t_64_sync_handler+0x134/0x150 el0t_64_sync+0x14c/0x15 Fixes: dfd0743 ("tee: handle lookup of shm with reference count 0") Signed-off-by: Pei Xiao <xiaopei01@kylinos.cn> Reviewed-by: Sumit Garg <sumit.garg@oss.qualcomm.com> Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>

BUG: kernel NULL pointer dereference, address: 00000000000002ec PGD 0 P4D 0 Oops: Oops: 0000 [#1] SMP PTI CPU: 28 UID: 0 PID: 343 Comm: kworker/28:1 Kdump: loaded Tainted: G OE 6.17.0-rc2+ #9 NONE Tainted: [O]=OOT_MODULE, [E]=UNSIGNED_MODULE Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.15.0-1 04/01/2014 Workqueue: smc_hs_wq smc_listen_work [smc] RIP: 0010:smc_ib_is_sg_need_sync+0x9e/0xd0 [smc] ... Call Trace: <TASK> smcr_buf_map_link+0x211/0x2a0 [smc] __smc_buf_create+0x522/0x970 [smc] smc_buf_create+0x3a/0x110 [smc] smc_find_rdma_v2_device_serv+0x18f/0x240 [smc] ? smc_vlan_by_tcpsk+0x7e/0xe0 [smc] smc_listen_find_device+0x1dd/0x2b0 [smc] smc_listen_work+0x30f/0x580 [smc] process_one_work+0x18c/0x340 worker_thread+0x242/0x360 kthread+0xe7/0x220 ret_from_fork+0x13a/0x160 ret_from_fork_asm+0x1a/0x30 </TASK> If the software RoCE device is used, ibdev->dma_device is a null pointer. As a result, the problem occurs. Null pointer detection is added to prevent problems. Fixes: 0ef69e7 ("net/smc: optimize for smc_sndbuf_sync_sg_for_device and smc_rmb_sync_sg_for_cpu") Signed-off-by: Liu Jian <liujian56@huawei.com> Reviewed-by: Guangguan Wang <guangguan.wang@linux.alibaba.com> Reviewed-by: Zhu Yanjun <yanjun.zhu@linux.dev> Reviewed-by: D. Wythe <alibuda@linux.alibaba.com> Link: https://patch.msgid.link/20250828124117.2622624-1-liujian56@huawei.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>

VXLAN FDB entries can point to either a remote destination or an FDB nexthop group. The latter is usually used in EVPN deployments where learning is disabled. However, when learning is enabled, an incoming packet might try to refresh an FDB entry that points to an FDB nexthop group and therefore does not have a remote. Such packets should be dropped, but they are only dropped after dereferencing the non-existent remote, resulting in a NPD [1] which can be reproduced using [2]. Fix by dropping such packets earlier. Remove the misleading comment from first_remote_rcu(). [1] BUG: kernel NULL pointer dereference, address: 0000000000000000 [...] CPU: 13 UID: 0 PID: 361 Comm: mausezahn Not tainted 6.17.0-rc1-virtme-g9f6b606b6b37 #1 PREEMPT(voluntary) Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.17.0-4.fc41 04/01/2014 RIP: 0010:vxlan_snoop+0x98/0x1e0 [...] Call Trace: <TASK> vxlan_encap_bypass+0x209/0x240 encap_bypass_if_local+0xb1/0x100 vxlan_xmit_one+0x1375/0x17e0 vxlan_xmit+0x6b4/0x15f0 dev_hard_start_xmit+0x5d/0x1c0 __dev_queue_xmit+0x246/0xfd0 packet_sendmsg+0x113a/0x1850 __sock_sendmsg+0x38/0x70 __sys_sendto+0x126/0x180 __x64_sys_sendto+0x24/0x30 do_syscall_64+0xa4/0x260 entry_SYSCALL_64_after_hwframe+0x4b/0x53 [2] #!/bin/bash ip address add 192.0.2.1/32 dev lo ip address add 192.0.2.2/32 dev lo ip nexthop add id 1 via 192.0.2.3 fdb ip nexthop add id 10 group 1 fdb ip link add name vx0 up type vxlan id 10010 local 192.0.2.1 dstport 12345 localbypass ip link add name vx1 up type vxlan id 10020 local 192.0.2.2 dstport 54321 learning bridge fdb add 00:11:22:33:44:55 dev vx0 self static dst 192.0.2.2 port 54321 vni 10020 bridge fdb add 00:aa:bb:cc:dd:ee dev vx1 self static nhid 10 mausezahn vx0 -a 00:aa:bb:cc:dd:ee -b 00:11:22:33:44:55 -c 1 -q Fixes: 1274e1c ("vxlan: ecmp support for mac fdb entries") Reported-by: Marlin Cremers <mcremers@cloudbear.nl> Reviewed-by: Petr Machata <petrm@nvidia.com> Signed-off-by: Ido Schimmel <idosch@nvidia.com> Reviewed-by: Nikolay Aleksandrov <razor@blackwall.org> Link: https://patch.msgid.link/20250901065035.159644-2-idosch@nvidia.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Ido Schimmel says: ==================== vxlan: Fix NPDs when using nexthop objects With FDB nexthop groups, VXLAN FDB entries do not necessarily point to a remote destination but rather to an FDB nexthop group. This means that first_remote_{rcu,rtnl}() can return NULL and a few places in the driver were not ready for that, resulting in NULL pointer dereferences. Patches #1-#2 fix these NPDs. Note that vxlan_fdb_find_uc() still dereferences the remote returned by first_remote_rcu() without checking that it is not NULL, but this function is only invoked by a single driver which vetoes the creation of FDB nexthop groups. I will patch this in net-next to make the code less fragile. Patch #3 adds a selftests which exercises these code paths and tests basic Tx functionality with FDB nexthop groups. I verified that the test crashes the kernel without the first two patches. ==================== Link: https://patch.msgid.link/20250901065035.159644-1-idosch@nvidia.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>

When transmitting a PTP frame which is timestamp using 2 step, the following warning appears if CONFIG_PROVE_LOCKING is enabled: ============================= [ BUG: Invalid wait context ] 6.17.0-rc1-00326-ge6160462704e #427 Not tainted ----------------------------- ptp4l/119 is trying to lock: c2a44ed4 (&vsc8531->ts_lock){+.+.}-{3:3}, at: vsc85xx_txtstamp+0x50/0xac other info that might help us debug this: context-{4:4} 4 locks held by ptp4l/119: #0: c145f068 (rcu_read_lock_bh){....}-{1:2}, at: __dev_queue_xmit+0x58/0x1440 #1: c29df974 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock){+...}-{2:2}, at: __dev_queue_xmit+0x5c4/0x1440 #2: c2aaaad0 (_xmit_ETHER#2){+.-.}-{2:2}, at: sch_direct_xmit+0x108/0x350 #3: c2aac170 (&lan966x->tx_lock){+.-.}-{2:2}, at: lan966x_port_xmit+0xd0/0x350 stack backtrace: CPU: 0 UID: 0 PID: 119 Comm: ptp4l Not tainted 6.17.0-rc1-00326-ge6160462704e #427 NONE Hardware name: Generic DT based system Call trace: unwind_backtrace from show_stack+0x10/0x14 show_stack from dump_stack_lvl+0x7c/0xac dump_stack_lvl from __lock_acquire+0x8e8/0x29dc __lock_acquire from lock_acquire+0x108/0x38c lock_acquire from __mutex_lock+0xb0/0xe78 __mutex_lock from mutex_lock_nested+0x1c/0x24 mutex_lock_nested from vsc85xx_txtstamp+0x50/0xac vsc85xx_txtstamp from lan966x_fdma_xmit+0xd8/0x3a8 lan966x_fdma_xmit from lan966x_port_xmit+0x1bc/0x350 lan966x_port_xmit from dev_hard_start_xmit+0xc8/0x2c0 dev_hard_start_xmit from sch_direct_xmit+0x8c/0x350 sch_direct_xmit from __dev_queue_xmit+0x680/0x1440 __dev_queue_xmit from packet_sendmsg+0xfa4/0x1568 packet_sendmsg from __sys_sendto+0x110/0x19c __sys_sendto from sys_send+0x18/0x20 sys_send from ret_fast_syscall+0x0/0x1c Exception stack(0xf0b05fa8 to 0xf0b05ff0) 5fa0: 00000001 0000000 0000000 0004b47a 0000003a 00000000 5fc0: 00000001 0000000 00000000 00000121 0004af58 00044874 00000000 00000000 5fe0: 00000001 bee9d420 00025a10 b6e75c7c So, instead of using the ts_lock for tx_queue, use the spinlock that skb_buff_head has. Reviewed-by: Vadim Fedorenko <vadim.fedorenko@linux.dev> Fixes: 7d272e6 ("net: phy: mscc: timestamping and PHC support") Signed-off-by: Horatiu Vultur <horatiu.vultur@microchip.com> Link: https://patch.msgid.link/20250902121259.3257536-1-horatiu.vultur@microchip.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Provide the actual decision function, which decides whether a time slice extension is granted in the exit to user mode path when NEED_RESCHED is evaluated. The decision is made in two stages. First an inline quick check to avoid going into the actual decision function. This checks whether: #1 the functionality is enabled #2 the exit is a return from interrupt to user mode #3 any TIF bit, which causes extra work is set. That includes TIF_RSEQ, which means the task was already scheduled out. The slow path, which implements the actual user space ABI, is invoked when: A) #1 is true, #2 is true and #3 is false It checks whether user space requested a slice extension by setting the request bit in the rseq slice_ctrl field. If so, it grants the extension and stores the slice expiry time, so that the actual exit code can double check whether the slice is already exhausted before going back. B) #1 - #3 are true _and_ a slice extension was granted in a previous loop iteration In this case the grant is revoked. In case that the user space access faults or invalid state is detected, the task is terminated with SIGSEGV. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://patch.msgid.link/20251215155709.195303303@linutronix.de

Luca Abeni added 6 commits January 22, 2014 12:51

Add a more detailed SCHED_DEADLINE description

900f57d

Few corrections to the real-time tasks section

aad5d75

Mention admission control where appropriate

538c068

The CBS guarantee can only be provided if a proper admission control is enforced... Mention this as early as possible.

Change "depleted" in "throttled"

257a972

"throttled" is more in line with the Linux kernel naming. Anyway, keep a reference to the term commonly used in literature.

Fix a cut'n'paste typo

ba3e7bb

Introduce the "replenishment time" concept

1481954

jlelli merged this pull request into jlelli:dl-doc Jan 27, 2014

Provide feedback

Saved searches

Use saved searches to filter your results more quickly

Comments

Dl doc#1

Dl doc#1
jlelli merged 6 commits intojlelli:dl-docfrom
lucabe72:dl-doc

lucabe72 commented Jan 27, 2014

Uh oh!

Reviewers

Assignees

Labels

Projects

Milestone

Development

Uh oh!

2 participants

Comments

Conversation

lucabe72 commented Jan 27, 2014

Uh oh!

Reviewers

Assignees

Labels

Projects

Milestone

Development

Uh oh!

2 participants