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INFO: rcu detected stall in hub_event

Status: upstream: reported on 2024/08/13 15:49
Reported-by: syzbot+88898457bbccad1cb490@syzkaller.appspotmail.com
First crash: 32d, last: 32d
▶ ▼ Similar bugs (5)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in hub_event usb C done 1001 7h40m 1759d 0/28 upstream: reported C repro on 2019/11/21 14:45
linux-6.1 INFO: rcu detected stall in hub_event origin:upstream C 4 14d 399d 0/3 upstream: reported C repro on 2023/08/12 16:34
android-5-15 BUG: soft lockup in hub_event 12 80d 151d 0/2 premoderation: reported on 2024/04/16 21:50
android-54 BUG: soft lockup in hub_event C 1 370d 370d 0/2 auto-obsoleted due to no activity on 2024/02/11 21:05
android-6-1 BUG: soft lockup in hub_event 1 458d 458d 0/2 auto-obsoleted due to no activity on 2023/09/12 05:32

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	1-...!: (3 ticks this GP) idle=307/1/0x4000000000000000 softirq=16468/16468 fqs=6 
	(detected by 0, t=10504 jiffies, g=24309, q=636)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 3662 Comm: kworker/1:8 Not tainted 5.15.164-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024
Workqueue: usb_hub_wq hub_event
RIP: 0010:should_resched arch/x86/include/asm/preempt.h:103 [inline]
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:161 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0xe0/0x130 kernel/locking/spinlock.c:194
Code: 4c 89 f7 e8 f2 90 8d f7 f6 44 24 21 02 75 4e 41 f7 c7 00 02 00 00 74 01 fb bf 01 00 00 00 e8 97 c6 1a f7 65 8b 05 58 cb c5 75 <85> c0 74 3f 48 c7 04 24 0e 36 e0 45 4b c7 04 2c 00 00 00 00 65 48
RSP: 0000:ffffc90000dd0c20 EFLAGS: 00000013
RAX: 0000000000010002 RBX: 1ffff920001ba188 RCX: 0000000000010003
RDX: 0000000000000000 RSI: 0000000000000004 RDI: 0000000000000001
RBP: ffffc90000dd0cb8 R08: dffffc0000000000 R09: fffffbfff22c750d
R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000
R13: 1ffff920001ba184 R14: ffffc90000dd0c40 R15: 0000000000000046
FS:  0000000000000000(0000) GS:ffff8880b9b00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fa45d81c020 CR3: 0000000016ba9000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <IRQ>
 debug_object_activate+0x2f4/0x4e0 lib/debugobjects.c:711
 debug_hrtimer_activate kernel/time/hrtimer.c:420 [inline]
 debug_activate kernel/time/hrtimer.c:475 [inline]
 enqueue_hrtimer+0x30/0x390 kernel/time/hrtimer.c:1084
 __run_hrtimer kernel/time/hrtimer.c:1703 [inline]
 __hrtimer_run_queues+0x6b6/0xcf0 kernel/time/hrtimer.c:1750
 hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1812
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1085 [inline]
 __sysvec_apic_timer_interrupt+0x139/0x470 arch/x86/kernel/apic/apic.c:1102
 sysvec_apic_timer_interrupt+0x8c/0xb0 arch/x86/kernel/apic/apic.c:1096
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:638
RIP: 0010:check_preemption_disabled+0x19/0x110 lib/smp_processor_id.c:14
Code: cc 48 c7 c7 a0 f7 d8 8a 48 c7 c6 e0 f7 d8 8a eb 00 41 57 41 56 41 54 53 48 83 ec 10 65 48 8b 04 25 28 00 00 00 48 89 44 24 08 <65> 8b 1d 08 f4 ce 75 65 8b 05 71 4e cf 75 a9 ff ff ff 7f 74 22 65
RSP: 0000:ffffc9000317e6f8 EFLAGS: 00000282
RAX: bf42f8f83afb0e00 RBX: ffff888063569bc8 RCX: 00000000000000a8
RDX: 00000000000000a8 RSI: ffffffff8ad8f7e0 RDI: ffffffff8ad8f7a0
RBP: ffff888063569bc8 R08: 00000000000000e8 R09: ffff888063569bc8
R10: 0000000000000000 R11: dffffc0000000001 R12: ffff888011df2b40
R13: ffff888011df2b40 R14: ffffffff81fc706b R15: 0000000000000dc0
 rcu_dynticks_curr_cpu_in_eqs kernel/rcu/tree.c:331 [inline]
 rcu_is_watching+0x11/0xa0 kernel/rcu/tree.c:1123
 trace_kmem_cache_alloc include/trace/events/kmem.h:54 [inline]
 kmem_cache_alloc+0x128/0x280 mm/slub.c:3235
 kmem_cache_zalloc include/linux/slab.h:711 [inline]
 __kernfs_new_node+0xdb/0x750 fs/kernfs/dir.c:593
 kernfs_new_node+0x136/0x230 fs/kernfs/dir.c:669
 __kernfs_create_file+0x45/0x2e0 fs/kernfs/file.c:985
 sysfs_add_file_mode_ns+0x308/0x3e0 fs/sysfs/file.c:317
 sysfs_merge_group+0x1fe/0x450 fs/sysfs/group.c:343
 dpm_sysfs_add+0xcf/0x270 drivers/base/power/sysfs.c:707
 device_add+0x702/0xfd0 drivers/base/core.c:3369
 snd_card_register+0x118/0x6a0 sound/core/init.c:882
 try_to_register_card+0x2f5/0x3c0 sound/usb/card.c:753
 usb_audio_probe+0x1a7c/0x2090 sound/usb/card.c:918
 usb_probe_interface+0x5c0/0xaf0 drivers/usb/core/driver.c:396
 really_probe+0x24e/0xb60 drivers/base/dd.c:595
 __driver_probe_device+0x1a2/0x3d0 drivers/base/dd.c:755
 driver_probe_device+0x50/0x420 drivers/base/dd.c:785
 __device_attach_driver+0x2b9/0x500 drivers/base/dd.c:907
 bus_for_each_drv+0x183/0x200 drivers/base/bus.c:427
 __device_attach+0x359/0x570 drivers/base/dd.c:979
 bus_probe_device+0xba/0x1e0 drivers/base/bus.c:487
 device_add+0xb48/0xfd0 drivers/base/core.c:3412
 usb_set_configuration+0x19dd/0x2020 drivers/usb/core/message.c:2165
 usb_generic_driver_probe+0x84/0x140 drivers/usb/core/generic.c:238
 usb_probe_device+0x130/0x260 drivers/usb/core/driver.c:293
 really_probe+0x24e/0xb60 drivers/base/dd.c:595
 __driver_probe_device+0x1a2/0x3d0 drivers/base/dd.c:755
 driver_probe_device+0x50/0x420 drivers/base/dd.c:785
 __device_attach_driver+0x2b9/0x500 drivers/base/dd.c:907
 bus_for_each_drv+0x183/0x200 drivers/base/bus.c:427
 __device_attach+0x359/0x570 drivers/base/dd.c:979
 bus_probe_device+0xba/0x1e0 drivers/base/bus.c:487
 device_add+0xb48/0xfd0 drivers/base/core.c:3412
 usb_new_device+0xc17/0x18e0 drivers/usb/core/hub.c:2593
 hub_port_connect drivers/usb/core/hub.c:5455 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5595 [inline]
 port_event drivers/usb/core/hub.c:5741 [inline]
 hub_event+0x2cdf/0x54c0 drivers/usb/core/hub.c:5823
 process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2310
 worker_thread+0xaca/0x1280 kernel/workqueue.c:2457
 kthread+0x3f6/0x4f0 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>
rcu: rcu_preempt kthread timer wakeup didn't happen for 7083 jiffies! g24309 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=0 timer-softirq=9312
rcu: rcu_preempt kthread starved for 7084 jiffies! g24309 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->cpu=0
rcu: 	Unless rcu_preempt kthread gets sufficient CPU time, OOM is now expected behavior.
rcu: RCU grace-period kthread stack dump:
task:rcu_preempt     state:I stack:26168 pid:   15 ppid:     2 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5030 [inline]
 __schedule+0x12c4/0x45b0 kernel/sched/core.c:6376
 schedule+0x11b/0x1f0 kernel/sched/core.c:6459
 schedule_timeout+0x1b9/0x300 kernel/time/timer.c:1914
 rcu_gp_fqs_loop+0x2bf/0x1080 kernel/rcu/tree.c:1972
 rcu_gp_kthread+0xa4/0x360 kernel/rcu/tree.c:2145
 kthread+0x3f6/0x4f0 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
NMI backtrace for cpu 0
CPU: 0 PID: 3965 Comm: kworker/0:11 Not tainted 5.15.164-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024
Workqueue: events fqdir_free_fn
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2d0 lib/dump_stack.c:106
 nmi_cpu_backtrace+0x46a/0x4a0 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x181/0x2a0 lib/nmi_backtrace.c:62
 trigger_single_cpu_backtrace include/linux/nmi.h:166 [inline]
 rcu_check_gp_kthread_starvation+0x1d2/0x240 kernel/rcu/tree_stall.h:487
 print_other_cpu_stall+0x137a/0x14d0 kernel/rcu/tree_stall.h:592
 check_cpu_stall kernel/rcu/tree_stall.h:745 [inline]
 rcu_pending kernel/rcu/tree.c:3932 [inline]
 rcu_sched_clock_irq+0xa38/0x1150 kernel/rcu/tree.c:2619
 update_process_times+0x196/0x200 kernel/time/timer.c:1818
 tick_sched_handle kernel/time/tick-sched.c:254 [inline]
 tick_sched_timer+0x386/0x550 kernel/time/tick-sched.c:1473
 __run_hrtimer kernel/time/hrtimer.c:1686 [inline]
 __hrtimer_run_queues+0x55b/0xcf0 kernel/time/hrtimer.c:1750
 hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1812
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1085 [inline]
 __sysvec_apic_timer_interrupt+0x139/0x470 arch/x86/kernel/apic/apic.c:1102
 sysvec_apic_timer_interrupt+0x8c/0xb0 arch/x86/kernel/apic/apic.c:1096
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:638
RIP: 0010:csd_lock_wait kernel/smp.c:440 [inline]
RIP: 0010:smp_call_function_single+0x297/0x530 kernel/smp.c:758
Code: 00 44 8b 6c 24 48 44 89 ee 83 e6 01 31 ff e8 c0 e4 0b 00 41 83 e5 01 75 0a e8 55 e1 0b 00 e9 eb 00 00 00 f3 90 42 0f b6 04 23 <84> c0 75 15 f7 44 24 48 01 00 00 00 0f 84 cd 00 00 00 e8 32 e1 0b
RSP: 0018:ffffc90003687a60 EFLAGS: 00000293
RAX: 0000000000000000 RBX: 1ffff920006d0f55 RCX: ffff888023fa5940
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc90003687b50 R08: ffffffff81748000 R09: ffffed1017367681
R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000
R13: 0000000000000001 R14: ffffc90003687aa8 R15: 0000000000000000
 rcu_barrier+0x262/0x4e0 kernel/rcu/tree.c:4078
 fqdir_free_fn+0x2e/0x130 net/ipv4/inet_fragment.c:163
 process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2310
 worker_thread+0xaca/0x1280 kernel/workqueue.c:2457
 kthread+0x3f6/0x4f0 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/08/13 15:49 linux-5.15.y 7e89efd3ae1c f21a18ca .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in hub_event
* Struck through repros no longer work on HEAD.