Netdev Archive on lore.kernel.org
help / color / mirror / Atom feed
* NETDEV WATCHDOG: WARNING: at net/sched/sch_generic.c:442 dev_watchdog
@ 2020-08-19 11:31 Naresh Kamboju
  2020-08-19 16:57 ` Steven Rostedt
  0 siblings, 1 reply; 4+ messages in thread
From: Naresh Kamboju @ 2020-08-19 11:31 UTC (permalink / raw)
  To: linux- stable, open list, Netdev
  Cc: Greg Kroah-Hartman, Sasha Levin, Steven Rostedt,
	Masami Hiramatsu, Leo Yan, Jamal Hadi Salim, Cong Wang,
	Jiri Pirko, David S. Miller, Jakub Kicinski, lkft-triage,
	LTP List

kernel warning noticed on x86_64 while running LTP tracing ftrace-stress-test
case. started noticing on the stable-rc linux-5.8.y branch.

This device booted with KASAN config and DYNAMIC tracing configs and more.
This reported issue is not easily reproducible.

metadata:
  git branch: linux-5.8.y
  git repo: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable-rc.git
  git commit: ad8c735b1497520df959f675718f39dca8cb8019
  git describe: v5.8.2
  make_kernelversion: 5.8.2
  kernel-config:
https://builds.tuxbuild.com/bOz0eAwkcraRiWALTW9D3Q/kernel.config


[   88.139387] Scheduler tracepoints stat_sleep, stat_iowait,
stat_blocked and stat_runtime require the kernel parameter
schedstats=enable or kernel.sched_schedstats=1
[   88.139387] Scheduler tracepoints stat_sleep, stat_iowait,
stat_blocked and stat_runtime require the kernel parameter
schedstats=enable or kernel.sched_schedstats=1
[  107.507991] ------------[ cut here ]------------
[  107.513103] NETDEV WATCHDOG: eth0 (igb): transmit queue 2 timed out
[  107.519973] WARNING: CPU: 1 PID: 331 at net/sched/sch_generic.c:442
dev_watchdog+0x4c7/0x4d0
[  107.528907] Modules linked in: x86_pkg_temp_thermal
[  107.534541] CPU: 1 PID: 331 Comm: systemd-journal Not tainted 5.8.2 #1
[  107.541480] Hardware name: Supermicro SYS-5019S-ML/X11SSH-F, BIOS
2.2 05/23/2018
[  107.549314] RIP: 0010:dev_watchdog+0x4c7/0x4d0
[  107.554226] Code: ff ff 48 8b 5d c8 c6 05 6d f7 94 01 01 48 89 df
e8 9e b4 f8 ff 44 89 e9 48 89 de 48 c7 c7 20 49 51 9c 48 89 c2 e8 91
7e e9 fe <0f> 0b e9 03 ff ff ff 66 90 e8 9b 23 db fe 55 48 89 e5 41 57
41 56
[  107.573476] RSP: 0018:ffff888230889d88 EFLAGS: 00010286
[  107.579264] RAX: 0000000000000000 RBX: ffff88822bbb0000 RCX: dffffc0000000000
[  107.586928] RDX: 1ffff11046114c99 RSI: ffffffff9a7e4dbe RDI: ffffffff9b7a6da7
[  107.594473] RBP: ffff888230889de0 R08: ffffffff9a7e4dd3 R09: ffffed1044de2529
[  107.602101] R10: ffff888226f12943 R11: ffffed1044de2528 R12: ffff88822bbb0440
[  107.609648] R13: 0000000000000002 R14: ffff88822bbb0388 R15: ffff88822bbb0380
[  107.617197] FS:  00007f8b471bb480(0000) GS:ffff888230880000(0000)
knlGS:0000000000000000
[  107.625698] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  107.631944] CR2: 0000000000000008 CR3: 0000000226a64001 CR4: 00000000003606e0
[  107.639496] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[  107.647092] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[  107.654661] Call Trace:
[  107.657735]  <IRQ>
[  107.663155]  ? ftrace_graph_caller+0xc0/0xc0
[  107.667929]  call_timer_fn+0x3b/0x1b0
[  107.672238]  ? netif_carrier_off+0x70/0x70
[  107.677771]  ? netif_carrier_off+0x70/0x70
[  107.682656]  ? ftrace_graph_caller+0xc0/0xc0
[  107.687379]  run_timer_softirq+0x3e8/0xa10
[  107.694653]  ? call_timer_fn+0x1b0/0x1b0
[  107.699382]  ? trace_event_raw_event_softirq+0xdd/0x150
[  107.706768]  ? ring_buffer_unlock_commit+0xf5/0x210
[  107.712213]  ? call_timer_fn+0x1b0/0x1b0
[  107.716625]  ? __do_softirq+0x155/0x467
Aug 22 04:21:44 intel-corei7-64 [  107.721972]  ? run_timer_softirq+0x5/0xa10
user.warn kernel[  107.727997]  ? asm_call_on_stack+0x12/0x20
: [  107.507991] ------------[ c[  107.735546]  ? ftrace_graph_caller+0xc0/0xc0
ut here ]-------[  107.740453]  __do_softirq+0x160/0x467
-----
[  107.745737]  ? hrtimer_interrupt+0x5/0x340
[  107.753961]  asm_call_on_stack+0x12/0x20
[  107.758672]  </IRQ>
[  107.761555]  do_softirq_own_stack+0x3f/0x50
[  107.766521]  ? ftrace_graph_caller+0xc0/0xc0
[  107.771246]  irq_exit_rcu+0xff/0x110
[  107.776116]  ? ftrace_graph_caller+0xc0/0xc0
[  107.780808]  sysvec_apic_timer_interrupt+0x38/0x90
[  107.786971]  asm_sysvec_apic_timer_interrupt+0x12/0x20
[  107.792598] RIP: 0010:profile_graph_return+0x111/0x1d0
[  107.798204] Code: 75 e1 48 8b 45 d0 f6 c4 02 75 16 50 9d e8 f7 ff
02 00 48 83 c4 10 5b 41 5c 41 5d 41 5e 41 5f 5d c3 e8 c3 fb 02 00 ff
75 d0 9d <48> 83 c4 10 5b 41 5c 41 5d 41 5e 41 5f 5d c3 48 8d 7b 20 e8
77 78
[  107.817416] RSP: 0018:ffff8882269b73a0 EFLAGS: 00000286
[  107.823201] RAX: ffff8882269b73d8 RBX: ffff8882269b7428 RCX: dffffc0000000000
[  107.830785] RDX: dffffc0000000000 RSI: ffffffff9a7e4dbe RDI: ffffffff9a7a955d
[  107.838411] RBP: ffff8882269b73d8 R08: ffffffff9a7e4dd3 R09: ffffed1044de2529
[  107.846072] R10: ffff888226f12943 R11: ffffed1044de2528 R12: ffff8882308a67c0
[  107.853621] R13: ffff888226f12930 R14: ffff8882308a67c8 R15: ffff88822c7e4000
[  107.863449]  ? ftrace_return_to_handler+0x1a3/0x230
Aug 22 04:21:44 [  107.869545]  ? ftrace_return_to_handler+0x18e/0x230
intel-corei7-64 [  107.875178]  ? profile_graph_return+0x10d/0x1d0
user.info kernel: [  107.513103][  107.882521]  ? unwind_dump+0x100/0x100
 NETDEV WATCHDOG: eth0 (igb): tr[  107.889054]  ?
unwind_next_frame.part.0+0xe0/0x360
ansmit queue 2 t[  107.895638]  ftrace_return_to_handler+0x18e/0x230
imed out
[  107.902594]  ? function_graph_enter+0x2d0/0x2d0
[  107.907616]  ? unwind_next_frame+0x23/0x30
[  107.912633]  ? unwind_dump+0x100/0x100
[  107.919304]  ? update_stack_state+0x1d4/0x290
[  107.926042]  return_to_handler+0x15/0x30
[  107.931071]  ? ftrace_graph_caller+0xc0/0xc0
[  107.935763]  ? unwind_next_frame.part.0+0xe0/0x360
[  107.941175]  ? unwind_next_frame.part.0+0x5/0x360
[  107.947344]  ? profile_setup.cold+0x9b/0x9b
[  107.953253]  ? ftrace_graph_caller+0xc0/0xc0
[  107.958020]  unwind_next_frame+0x23/0x30
[  107.963015]  ? ftrace_graph_caller+0xc0/0xc0
[  107.967701]  arch_stack_walk+0x8c/0xf0
[  107.974194]  ? vfs_open+0x58/0x60
[  107.979965]  ? ftrace_graph_caller+0xc0/0xc0
[  107.984652]  stack_trace_save+0x94/0xc0
[  107.989565]  ? stack_trace_consume_entry+0x90/0x90
[  107.995792]  ? stack_trace_save+0x5/0xc0
[  108.000536]  ? trace_hardirqs_on+0x3a/0x120
[  108.005959]  ? stack_trace_save+0x5/0xc0
[  108.007220]  ? ftrace_graph_caller+0xc0/0xc0
[  108.007464]  save_stack+0x23/0x50
[  108.007909]  ? save_stack+0x23/0x50
[  108.008225]  ? __kasan_kmalloc.constprop.0+0xcf/0xe0
[  108.008517]  ? kasan_kmalloc+0x9/0x10
Aug 22 04:21:44 [  108.008809]  ? kmem_cache_alloc_trace+0xf6/0x270
intel-corei7-64 [  108.009207]  ? single_open+0x3b/0xf0
user.warn kernel[  108.044913]  ? proc_single_open+0x1b/0x20
: [  107.519973][  108.050304]  ? do_dentry_open+0x2a6/0x6f0
 WARNING: CPU: 1 PID: 331 at net[  108.057406]  ? __kasan_check_read+0x11/0x20
/sched/sch_gener[  108.063044]  ? rb_commit+0xef/0x630
ic.c:442 dev_watchdog+0x4c7/0x4d0
[  108.070497]  ? __kasan_check_read+0x11/0x20
[  108.075391]  ? ring_buffer_unlock_commit+0x102/0x210
[  108.082301]  ? trace_buffer_unlock_commit_regs+0x171/0x1d0
[  108.090197]  ? trace_event_buffer_commit+0xfb/0x3d0
[  108.097668]  ? ftrace_graph_caller+0xc0/0xc0
[  108.102681]  ? trace_event_raw_event_kmem_alloc+0x7c/0xe0
[  108.109083]  ? kasan_unpoison_shadow+0x38/0x50
[  108.114780]  __kasan_kmalloc.constprop.0+0xcf/0xe0
[  108.121927]  kasan_kmalloc+0x9/0x10
[  108.126280]  kmem_cache_alloc_trace+0xf6/0x270
[  108.131499]  ? ftrace_graph_caller+0xc0/0xc0
[  108.136690]  ? proc_cwd_link+0x140/0x140
[  108.141797]  ? ftrace_graph_caller+0xc0/0xc0
[  108.146568]  single_open+0x3b/0xf0
[  108.151695]  ? ftrace_graph_caller+0xc0/0xc0
[  108.156386]  proc_single_open+0x1b/0x20
[  108.161083]  ? ftrace_graph_caller+0xc0/0xc0
[  108.165772]  do_dentry_open+0x2a6/0x6f0
[  108.170282]  ? vfs_open+0x4a/0x60
[  108.175328]  ? sched_open+0x20/0x20
[  108.181406]  ? ftrace_graph_caller+0xc0/0xc0
[  108.186131]  vfs_open+0x58/0x60
[  108.190568]  ? ftrace_graph_caller+0xc0/0xc0
[  108.195258]  path_openat+0x153b/0x1ab0
[  108.202219]  ? __srcu_read_lock+0x50/0x50
[  108.209143]  ? vfs_mkobj+0x270/0x270
[  108.210188]  ? ftrace_graph_caller+0x81/0xc0
[  108.210721]  ? ftrace_return_to_handler+0x1a3/0x230
[  108.212065]  ? function_graph_enter+0x2d0/0x2d0
[  108.212812]  ? do_filp_open+0x91/0x1b0
[  108.213426]  ? do_filp_open+0x107/0x1b0
[  108.214662]  ? path_openat+0x5/0x1ab0
[  108.217377]  ? ftrace_graph_caller+0xc0/0xc0
[  108.217621]  do_filp_open+0x124/0x1b0
[  108.219009]  ? may_open_dev+0x50/0x50
[  108.222371]  ? prepare_ftrace_return+0x7b/0xa0
[  108.224144]  ? ftrace_graph_caller+0x81/0xc0
[  108.224461]  ? function_graph_enter+0x2d0/0x2d0
[  108.226641]  ? ftrace_return_to_handler+0x1a3/0x230
[  108.228414]  ? do_filp_open+0x5/0x1b0
[  108.231132]  ? ftrace_graph_caller+0xc0/0xc0
[  108.231376]  do_sys_openat2+0x31d/0x410
[  108.233412]  ? file_open_root+0x210/0x210
[  108.235616]  ? do_sys_openat2+0x5/0x410
[  108.236230]  ? ftrace_graph_caller+0x81/0xc0
[  108.238435]  ? ftrace_graph_caller+0xc0/0xc0
[  108.238678]  do_sys_open+0x99/0xf0
[  108.239555]  ? filp_open+0x60/0x60
[  108.240816]  ? do_sys_open+0x5/0xf0
[  108.242372]  ? do_sys_open+0x5/0xf0
[  108.243632]  ? ftrace_graph_caller+0xc0/0xc0
[  108.243959]  __x64_sys_openat+0x59/0x70
[  108.245508]  ? ftrace_graph_caller+0xc0/0xc0
[  108.245752]  do_syscall_64+0x51/0x90
[  108.246951]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
[  108.247244] RIP: 0033:0x7f8b46680d20
[  108.247512] Code: 25 00 00 41 00 3d 00 00 41 00 74 36 48 8d 05 ef
eb 2c 00 8b 00 85 c0 75 5a 89 f2 b8 01 01 00 00 48 89 fe bf 9c ff ff
ff 0f 05 <48> 3d 00 f0 ff ff 0f 87 84 00 00 00 48 83 c4 68 5b 5d c3 0f
1f 44
[  108.247777] RSP: 002b:00007ffd2d0f21d0 EFLAGS: 00000246 ORIG_RAX:
0000000000000101
[  108.248248] RAX: ffffffffffffffda RBX: 00005635a1dcc260 RCX: 00007f8b46680d20
[  108.248466] RDX: 0000000000080000 RSI: 00007ffd2d0f2380 RDI: 00000000ffffff9c
[  108.248684] RBP: 0000000000000008 R08: 0000000000000008 R09: 0000000000000001
[  108.248984] R10: 0000000000000000 R11: 0000000000000246 R12: 00007f8b46cb2977
[  108.249226] R13: 00007f8b46cb2977 R14: 0000000000000001 R15: 0000000000000000
[  108.254504] ---[ end trace 743b6da37b9f0ee8 ]---

full test log link,
https://qa-reports.linaro.org/lkft/linux-stable-rc-5.8-oe/build/v5.8.2/testrun/3085886/suite/linux-log-parser/test/check-kernel-warning-1683943/log

Reported-by: Naresh Kamboju <naresh.kamboju@linaro.org>

-- 
Linaro LKFT
https://lkft.linaro.org

^ permalink raw reply	[flat|nested] 4+ messages in thread

* Re: NETDEV WATCHDOG: WARNING: at net/sched/sch_generic.c:442 dev_watchdog
  2020-08-19 11:31 NETDEV WATCHDOG: WARNING: at net/sched/sch_generic.c:442 dev_watchdog Naresh Kamboju
@ 2020-08-19 16:57 ` Steven Rostedt
  2020-08-19 17:29   ` Jesse Brandeburg
  0 siblings, 1 reply; 4+ messages in thread
From: Steven Rostedt @ 2020-08-19 16:57 UTC (permalink / raw)
  To: Naresh Kamboju
  Cc: linux- stable, open list, Netdev, Greg Kroah-Hartman,
	Sasha Levin, Masami Hiramatsu, Leo Yan, Jamal Hadi Salim,
	Cong Wang, Jiri Pirko, David S. Miller, Jakub Kicinski,
	lkft-triage, LTP List

On Wed, 19 Aug 2020 17:01:06 +0530
Naresh Kamboju <naresh.kamboju@linaro.org> wrote:

> kernel warning noticed on x86_64 while running LTP tracing ftrace-stress-test
> case. started noticing on the stable-rc linux-5.8.y branch.
> 
> This device booted with KASAN config and DYNAMIC tracing configs and more.
> This reported issue is not easily reproducible.
> 
> metadata:
>   git branch: linux-5.8.y
>   git repo: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable-rc.git
>   git commit: ad8c735b1497520df959f675718f39dca8cb8019
>   git describe: v5.8.2
>   make_kernelversion: 5.8.2
>   kernel-config:
> https://builds.tuxbuild.com/bOz0eAwkcraRiWALTW9D3Q/kernel.config
> 
> 
> [   88.139387] Scheduler tracepoints stat_sleep, stat_iowait,
> stat_blocked and stat_runtime require the kernel parameter
> schedstats=enable or kernel.sched_schedstats=1
> [   88.139387] Scheduler tracepoints stat_sleep, stat_iowait,
> stat_blocked and stat_runtime require the kernel parameter
> schedstats=enable or kernel.sched_schedstats=1
> [  107.507991] ------------[ cut here ]------------
> [  107.513103] NETDEV WATCHDOG: eth0 (igb): transmit queue 2 timed out
> [  107.519973] WARNING: CPU: 1 PID: 331 at net/sched/sch_generic.c:442
> dev_watchdog+0x4c7/0x4d0
> [  107.528907] Modules linked in: x86_pkg_temp_thermal
> [  107.534541] CPU: 1 PID: 331 Comm: systemd-journal Not tainted 5.8.2 #1
> [  107.541480] Hardware name: Supermicro SYS-5019S-ML/X11SSH-F, BIOS
> 2.2 05/23/2018
> [  107.549314] RIP: 0010:dev_watchdog+0x4c7/0x4d0
> [  107.554226] Code: ff ff 48 8b 5d c8 c6 05 6d f7 94 01 01 48 89 df
> e8 9e b4 f8 ff 44 89 e9 48 89 de 48 c7 c7 20 49 51 9c 48 89 c2 e8 91
> 7e e9 fe <0f> 0b e9 03 ff ff ff 66 90 e8 9b 23 db fe 55 48 89 e5 41 57

I've triggered this myself in my testing, and I assumed that adding the
overhead of tracing and here KASAN too, made some watchdog a bit
unhappy. By commenting out the warning, I've seen no ill effects.

Perhaps this is something we need to dig a bit deeper into.

-- Steve


> 41 56
> [  107.573476] RSP: 0018:ffff888230889d88 EFLAGS: 00010286
> [  107.579264] RAX: 0000000000000000 RBX: ffff88822bbb0000 RCX: dffffc0000000000
> [  107.586928] RDX: 1ffff11046114c99 RSI: ffffffff9a7e4dbe RDI: ffffffff9b7a6da7
> [  107.594473] RBP: ffff888230889de0 R08: ffffffff9a7e4dd3 R09: ffffed1044de2529
> [  107.602101] R10: ffff888226f12943 R11: ffffed1044de2528 R12: ffff88822bbb0440
> [  107.609648] R13: 0000000000000002 R14: ffff88822bbb0388 R15: ffff88822bbb0380
> [  107.617197] FS:  00007f8b471bb480(0000) GS:ffff888230880000(0000)
> knlGS:0000000000000000
> [  107.625698] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> [  107.631944] CR2: 0000000000000008 CR3: 0000000226a64001 CR4: 00000000003606e0
> [  107.639496] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
> [  107.647092] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
> [  107.654661] Call Trace:
> [  107.657735]  <IRQ>
> [  107.663155]  ? ftrace_graph_caller+0xc0/0xc0
> [  107.667929]  call_timer_fn+0x3b/0x1b0
> [  107.672238]  ? netif_carrier_off+0x70/0x70
> [  107.677771]  ? netif_carrier_off+0x70/0x70
> [  107.682656]  ? ftrace_graph_caller+0xc0/0xc0
> [  107.687379]  run_timer_softirq+0x3e8/0xa10
> [  107.694653]  ? call_timer_fn+0x1b0/0x1b0
> [  107.699382]  ? trace_event_raw_event_softirq+0xdd/0x150
> [  107.706768]  ? ring_buffer_unlock_commit+0xf5/0x210
> [  107.712213]  ? call_timer_fn+0x1b0/0x1b0
> [  107.716625]  ? __do_softirq+0x155/0x467
> Aug 22 04:21:44 intel-corei7-64 [  107.721972]  ? run_timer_softirq+0x5/0xa10
> user.warn kernel[  107.727997]  ? asm_call_on_stack+0x12/0x20
> : [  107.507991] ------------[ c[  107.735546]  ? ftrace_graph_caller+0xc0/0xc0
> ut here ]-------[  107.740453]  __do_softirq+0x160/0x467
> -----
> [  107.745737]  ? hrtimer_interrupt+0x5/0x340
> [  107.753961]  asm_call_on_stack+0x12/0x20
> [  107.758672]  </IRQ>
> [  107.761555]  do_softirq_own_stack+0x3f/0x50
> [  107.766521]  ? ftrace_graph_caller+0xc0/0xc0
> [  107.771246]  irq_exit_rcu+0xff/0x110
> [  107.776116]  ? ftrace_graph_caller+0xc0/0xc0
> [  107.780808]  sysvec_apic_timer_interrupt+0x38/0x90
> [  107.786971]  asm_sysvec_apic_timer_interrupt+0x12/0x20
> [  107.792598] RIP: 0010:profile_graph_return+0x111/0x1d0
> [  107.798204] Code: 75 e1 48 8b 45 d0 f6 c4 02 75 16 50 9d e8 f7 ff
> 02 00 48 83 c4 10 5b 41 5c 41 5d 41 5e 41 5f 5d c3 e8 c3 fb 02 00 ff
> 75 d0 9d <48> 83 c4 10 5b 41 5c 41 5d 41 5e 41 5f 5d c3 48 8d 7b 20 e8
> 77 78
> [  107.817416] RSP: 0018:ffff8882269b73a0 EFLAGS: 00000286
> [  107.823201] RAX: ffff8882269b73d8 RBX: ffff8882269b7428 RCX: dffffc0000000000
> [  107.830785] RDX: dffffc0000000000 RSI: ffffffff9a7e4dbe RDI: ffffffff9a7a955d
> [  107.838411] RBP: ffff8882269b73d8 R08: ffffffff9a7e4dd3 R09: ffffed1044de2529
> [  107.846072] R10: ffff888226f12943 R11: ffffed1044de2528 R12: ffff8882308a67c0
> [  107.853621] R13: ffff888226f12930 R14: ffff8882308a67c8 R15: ffff88822c7e4000
> [  107.863449]  ? ftrace_return_to_handler+0x1a3/0x230
> Aug 22 04:21:44 [  107.869545]  ? ftrace_return_to_handler+0x18e/0x230
> intel-corei7-64 [  107.875178]  ? profile_graph_return+0x10d/0x1d0
> user.info kernel: [  107.513103][  107.882521]  ? unwind_dump+0x100/0x100
>  NETDEV WATCHDOG: eth0 (igb): tr[  107.889054]  ?
> unwind_next_frame.part.0+0xe0/0x360
> ansmit queue 2 t[  107.895638]  ftrace_return_to_handler+0x18e/0x230
> imed out
> [  107.902594]  ? function_graph_enter+0x2d0/0x2d0
> [  107.907616]  ? unwind_next_frame+0x23/0x30
> [  107.912633]  ? unwind_dump+0x100/0x100
> [  107.919304]  ? update_stack_state+0x1d4/0x290
> [  107.926042]  return_to_handler+0x15/0x30
> [  107.931071]  ? ftrace_graph_caller+0xc0/0xc0
> [  107.935763]  ? unwind_next_frame.part.0+0xe0/0x360
> [  107.941175]  ? unwind_next_frame.part.0+0x5/0x360
> [  107.947344]  ? profile_setup.cold+0x9b/0x9b
> [  107.953253]  ? ftrace_graph_caller+0xc0/0xc0
> [  107.958020]  unwind_next_frame+0x23/0x30
> [  107.963015]  ? ftrace_graph_caller+0xc0/0xc0
> [  107.967701]  arch_stack_walk+0x8c/0xf0
> [  107.974194]  ? vfs_open+0x58/0x60
> [  107.979965]  ? ftrace_graph_caller+0xc0/0xc0
> [  107.984652]  stack_trace_save+0x94/0xc0
> [  107.989565]  ? stack_trace_consume_entry+0x90/0x90
> [  107.995792]  ? stack_trace_save+0x5/0xc0
> [  108.000536]  ? trace_hardirqs_on+0x3a/0x120
> [  108.005959]  ? stack_trace_save+0x5/0xc0
> [  108.007220]  ? ftrace_graph_caller+0xc0/0xc0
> [  108.007464]  save_stack+0x23/0x50
> [  108.007909]  ? save_stack+0x23/0x50
> [  108.008225]  ? __kasan_kmalloc.constprop.0+0xcf/0xe0
> [  108.008517]  ? kasan_kmalloc+0x9/0x10
> Aug 22 04:21:44 [  108.008809]  ? kmem_cache_alloc_trace+0xf6/0x270
> intel-corei7-64 [  108.009207]  ? single_open+0x3b/0xf0
> user.warn kernel[  108.044913]  ? proc_single_open+0x1b/0x20
> : [  107.519973][  108.050304]  ? do_dentry_open+0x2a6/0x6f0
>  WARNING: CPU: 1 PID: 331 at net[  108.057406]  ? __kasan_check_read+0x11/0x20
> /sched/sch_gener[  108.063044]  ? rb_commit+0xef/0x630
> ic.c:442 dev_watchdog+0x4c7/0x4d0
> [  108.070497]  ? __kasan_check_read+0x11/0x20
> [  108.075391]  ? ring_buffer_unlock_commit+0x102/0x210
> [  108.082301]  ? trace_buffer_unlock_commit_regs+0x171/0x1d0
> [  108.090197]  ? trace_event_buffer_commit+0xfb/0x3d0
> [  108.097668]  ? ftrace_graph_caller+0xc0/0xc0
> [  108.102681]  ? trace_event_raw_event_kmem_alloc+0x7c/0xe0
> [  108.109083]  ? kasan_unpoison_shadow+0x38/0x50
> [  108.114780]  __kasan_kmalloc.constprop.0+0xcf/0xe0
> [  108.121927]  kasan_kmalloc+0x9/0x10
> [  108.126280]  kmem_cache_alloc_trace+0xf6/0x270
> [  108.131499]  ? ftrace_graph_caller+0xc0/0xc0
> [  108.136690]  ? proc_cwd_link+0x140/0x140
> [  108.141797]  ? ftrace_graph_caller+0xc0/0xc0
> [  108.146568]  single_open+0x3b/0xf0
> [  108.151695]  ? ftrace_graph_caller+0xc0/0xc0
> [  108.156386]  proc_single_open+0x1b/0x20
> [  108.161083]  ? ftrace_graph_caller+0xc0/0xc0
> [  108.165772]  do_dentry_open+0x2a6/0x6f0
> [  108.170282]  ? vfs_open+0x4a/0x60
> [  108.175328]  ? sched_open+0x20/0x20
> [  108.181406]  ? ftrace_graph_caller+0xc0/0xc0
> [  108.186131]  vfs_open+0x58/0x60
> [  108.190568]  ? ftrace_graph_caller+0xc0/0xc0
> [  108.195258]  path_openat+0x153b/0x1ab0
> [  108.202219]  ? __srcu_read_lock+0x50/0x50
> [  108.209143]  ? vfs_mkobj+0x270/0x270
> [  108.210188]  ? ftrace_graph_caller+0x81/0xc0
> [  108.210721]  ? ftrace_return_to_handler+0x1a3/0x230
> [  108.212065]  ? function_graph_enter+0x2d0/0x2d0
> [  108.212812]  ? do_filp_open+0x91/0x1b0
> [  108.213426]  ? do_filp_open+0x107/0x1b0
> [  108.214662]  ? path_openat+0x5/0x1ab0
> [  108.217377]  ? ftrace_graph_caller+0xc0/0xc0
> [  108.217621]  do_filp_open+0x124/0x1b0
> [  108.219009]  ? may_open_dev+0x50/0x50
> [  108.222371]  ? prepare_ftrace_return+0x7b/0xa0
> [  108.224144]  ? ftrace_graph_caller+0x81/0xc0
> [  108.224461]  ? function_graph_enter+0x2d0/0x2d0
> [  108.226641]  ? ftrace_return_to_handler+0x1a3/0x230
> [  108.228414]  ? do_filp_open+0x5/0x1b0
> [  108.231132]  ? ftrace_graph_caller+0xc0/0xc0
> [  108.231376]  do_sys_openat2+0x31d/0x410
> [  108.233412]  ? file_open_root+0x210/0x210
> [  108.235616]  ? do_sys_openat2+0x5/0x410
> [  108.236230]  ? ftrace_graph_caller+0x81/0xc0
> [  108.238435]  ? ftrace_graph_caller+0xc0/0xc0
> [  108.238678]  do_sys_open+0x99/0xf0
> [  108.239555]  ? filp_open+0x60/0x60
> [  108.240816]  ? do_sys_open+0x5/0xf0
> [  108.242372]  ? do_sys_open+0x5/0xf0
> [  108.243632]  ? ftrace_graph_caller+0xc0/0xc0
> [  108.243959]  __x64_sys_openat+0x59/0x70
> [  108.245508]  ? ftrace_graph_caller+0xc0/0xc0
> [  108.245752]  do_syscall_64+0x51/0x90
> [  108.246951]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
> [  108.247244] RIP: 0033:0x7f8b46680d20
> [  108.247512] Code: 25 00 00 41 00 3d 00 00 41 00 74 36 48 8d 05 ef
> eb 2c 00 8b 00 85 c0 75 5a 89 f2 b8 01 01 00 00 48 89 fe bf 9c ff ff
> ff 0f 05 <48> 3d 00 f0 ff ff 0f 87 84 00 00 00 48 83 c4 68 5b 5d c3 0f
> 1f 44
> [  108.247777] RSP: 002b:00007ffd2d0f21d0 EFLAGS: 00000246 ORIG_RAX:
> 0000000000000101
> [  108.248248] RAX: ffffffffffffffda RBX: 00005635a1dcc260 RCX: 00007f8b46680d20
> [  108.248466] RDX: 0000000000080000 RSI: 00007ffd2d0f2380 RDI: 00000000ffffff9c
> [  108.248684] RBP: 0000000000000008 R08: 0000000000000008 R09: 0000000000000001
> [  108.248984] R10: 0000000000000000 R11: 0000000000000246 R12: 00007f8b46cb2977
> [  108.249226] R13: 00007f8b46cb2977 R14: 0000000000000001 R15: 0000000000000000
> [  108.254504] ---[ end trace 743b6da37b9f0ee8 ]---
> 
> full test log link,
> https://qa-reports.linaro.org/lkft/linux-stable-rc-5.8-oe/build/v5.8.2/testrun/3085886/suite/linux-log-parser/test/check-kernel-warning-1683943/log
> 
> Reported-by: Naresh Kamboju <naresh.kamboju@linaro.org>
> 


^ permalink raw reply	[flat|nested] 4+ messages in thread

* Re: NETDEV WATCHDOG: WARNING: at net/sched/sch_generic.c:442 dev_watchdog
  2020-08-19 16:57 ` Steven Rostedt
@ 2020-08-19 17:29   ` Jesse Brandeburg
  2020-08-19 19:17     ` Steven Rostedt
  0 siblings, 1 reply; 4+ messages in thread
From: Jesse Brandeburg @ 2020-08-19 17:29 UTC (permalink / raw)
  To: Steven Rostedt
  Cc: Naresh Kamboju, linux- stable, open list, Netdev,
	Greg Kroah-Hartman, Sasha Levin, Masami Hiramatsu, Leo Yan,
	Jamal Hadi Salim, Cong Wang, Jiri Pirko, David S. Miller,
	Jakub Kicinski, lkft-triage, LTP List

Steven Rostedt wrote:

> On Wed, 19 Aug 2020 17:01:06 +0530
> Naresh Kamboju <naresh.kamboju@linaro.org> wrote:
> 
> > kernel warning noticed on x86_64 while running LTP tracing ftrace-stress-test
> > case. started noticing on the stable-rc linux-5.8.y branch.
> > 
> > This device booted with KASAN config and DYNAMIC tracing configs and more.
> > This reported issue is not easily reproducible.
> > 
> > metadata:
> >   git branch: linux-5.8.y
> >   git repo: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable-rc.git
> >   git commit: ad8c735b1497520df959f675718f39dca8cb8019
> >   git describe: v5.8.2
> >   make_kernelversion: 5.8.2
> >   kernel-config:
> > https://builds.tuxbuild.com/bOz0eAwkcraRiWALTW9D3Q/kernel.config
> > 
> > 
> > [   88.139387] Scheduler tracepoints stat_sleep, stat_iowait,
> > stat_blocked and stat_runtime require the kernel parameter
> > schedstats=enable or kernel.sched_schedstats=1
> > [   88.139387] Scheduler tracepoints stat_sleep, stat_iowait,
> > stat_blocked and stat_runtime require the kernel parameter
> > schedstats=enable or kernel.sched_schedstats=1
> > [  107.507991] ------------[ cut here ]------------
> > [  107.513103] NETDEV WATCHDOG: eth0 (igb): transmit queue 2 timed out
> > [  107.519973] WARNING: CPU: 1 PID: 331 at net/sched/sch_generic.c:442
> > dev_watchdog+0x4c7/0x4d0
> > [  107.528907] Modules linked in: x86_pkg_temp_thermal
> > [  107.534541] CPU: 1 PID: 331 Comm: systemd-journal Not tainted 5.8.2 #1
> > [  107.541480] Hardware name: Supermicro SYS-5019S-ML/X11SSH-F, BIOS
> > 2.2 05/23/2018
> > [  107.549314] RIP: 0010:dev_watchdog+0x4c7/0x4d0
> > [  107.554226] Code: ff ff 48 8b 5d c8 c6 05 6d f7 94 01 01 48 89 df
> > e8 9e b4 f8 ff 44 89 e9 48 89 de 48 c7 c7 20 49 51 9c 48 89 c2 e8 91
> > 7e e9 fe <0f> 0b e9 03 ff ff ff 66 90 e8 9b 23 db fe 55 48 89 e5 41 57
> 
> I've triggered this myself in my testing, and I assumed that adding the
> overhead of tracing and here KASAN too, made some watchdog a bit
> unhappy. By commenting out the warning, I've seen no ill effects.
> 
> Perhaps this is something we need to dig a bit deeper into.

Looked into it a little, igb uses a timeout of 5 seconds, and the stack
prints the warning if we haven't completed the transmit in that time.

What I don't understand in the stack trace is this:
> > [  107.654661] Call Trace:
> > [  107.657735]  <IRQ>
> > [  107.663155]  ? ftrace_graph_caller+0xc0/0xc0
> > [  107.667929]  call_timer_fn+0x3b/0x1b0
> > [  107.672238]  ? netif_carrier_off+0x70/0x70
> > [  107.677771]  ? netif_carrier_off+0x70/0x70
> > [  107.682656]  ? ftrace_graph_caller+0xc0/0xc0
> > [  107.687379]  run_timer_softirq+0x3e8/0xa10
> > [  107.694653]  ? call_timer_fn+0x1b0/0x1b0
> > [  107.699382]  ? trace_event_raw_event_softirq+0xdd/0x150
> > [  107.706768]  ? ring_buffer_unlock_commit+0xf5/0x210
> > [  107.712213]  ? call_timer_fn+0x1b0/0x1b0
> > [  107.716625]  ? __do_softirq+0x155/0x467


If the carrier was turned off by something, that could cause the stack
to timeout since it appears the driver didn't call this itself after
finishing all transmits like it normally would have.

Is the trace above correct? Usually the ? indicate unsure backtrace due
to missing symbols, right?

^ permalink raw reply	[flat|nested] 4+ messages in thread

* Re: NETDEV WATCHDOG: WARNING: at net/sched/sch_generic.c:442 dev_watchdog
  2020-08-19 17:29   ` Jesse Brandeburg
@ 2020-08-19 19:17     ` Steven Rostedt
  0 siblings, 0 replies; 4+ messages in thread
From: Steven Rostedt @ 2020-08-19 19:17 UTC (permalink / raw)
  To: Jesse Brandeburg
  Cc: Naresh Kamboju, linux- stable, open list, Netdev,
	Greg Kroah-Hartman, Sasha Levin, Masami Hiramatsu, Leo Yan,
	Jamal Hadi Salim, Cong Wang, Jiri Pirko, David S. Miller,
	Jakub Kicinski, lkft-triage, LTP List

On Wed, 19 Aug 2020 10:29:09 -0700
Jesse Brandeburg <jesse.brandeburg@intel.com> wrote:


> What I don't understand in the stack trace is this:
> > > [  107.654661] Call Trace:
> > > [  107.657735]  <IRQ>
> > > [  107.663155]  ? ftrace_graph_caller+0xc0/0xc0
> > > [  107.667929]  call_timer_fn+0x3b/0x1b0
> > > [  107.672238]  ? netif_carrier_off+0x70/0x70
> > > [  107.677771]  ? netif_carrier_off+0x70/0x70
> > > [  107.682656]  ? ftrace_graph_caller+0xc0/0xc0
> > > [  107.687379]  run_timer_softirq+0x3e8/0xa10
> > > [  107.694653]  ? call_timer_fn+0x1b0/0x1b0
> > > [  107.699382]  ? trace_event_raw_event_softirq+0xdd/0x150
> > > [  107.706768]  ? ring_buffer_unlock_commit+0xf5/0x210
> > > [  107.712213]  ? call_timer_fn+0x1b0/0x1b0
> > > [  107.716625]  ? __do_softirq+0x155/0x467  
> 
> 
> If the carrier was turned off by something, that could cause the stack
> to timeout since it appears the driver didn't call this itself after
> finishing all transmits like it normally would have.
> 
> Is the trace above correct? Usually the ? indicate unsure backtrace due
> to missing symbols, right?

The "?" means that there wasn't a stack frame to confirm that this was
the true call stack. What happens is that the scan of the stack will
look for any address in the stack that is for a function. If it finds
one, it will print it and add a "?" to that address. Basically, those
functions with the "?" are just addresses found in the stack but was not
part of a stack frame link.

-- Steve

^ permalink raw reply	[flat|nested] 4+ messages in thread

end of thread, other threads:[~2020-08-19 19:17 UTC | newest]

Thread overview: 4+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2020-08-19 11:31 NETDEV WATCHDOG: WARNING: at net/sched/sch_generic.c:442 dev_watchdog Naresh Kamboju
2020-08-19 16:57 ` Steven Rostedt
2020-08-19 17:29   ` Jesse Brandeburg
2020-08-19 19:17     ` Steven Rostedt

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).