rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 0-...!: (1 GPs behind) idle=e0f4/1/0x4000000000000000 softirq=110563/110566 fqs=9
rcu: (detected by 1, t=10502 jiffies, g=77821, q=360 ncpus=2)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 3 Comm: pool_workqueue_ Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:__hrtimer_run_queues+0x244/0xc30 kernel/time/hrtimer.c:1838
Code: 74 24 20 4c 89 f0 48 c1 e8 03 42 80 3c 28 00 74 08 4c 89 f7 e8 2d ad 78 00 4d 8b 36 48 89 df 4c 89 f6 e8 0f 8f 12 00 4c 39 f3 <0f> 8c 01 09 00 00 48 8b 84 24 a0 00 00 00 42 0f b6 04 28 84 c0 0f
RSP: 0018:ffffc90000007d40 EFLAGS: 00000006
RAX: ffffffff81ae6901 RBX: 1bc16d674f0a5e0a RCX: ffff88801befbd00
RDX: 0000000000010000 RSI: 188d1d5aec000000 RDI: 1bc16d674f0a5e0a
RBP: ffffc90000007e90 R08: ffff888033d89317 R09: ffff888033d89300
R10: dffffc0000000000 R11: ffffed10067b1263 R12: ffff888033d89300
R13: dffffc0000000000 R14: 188d1d5aec000000 R15: ffff8880b8628440
FS: 0000000000000000(0000) GS:ffff888125e1f000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007efd04389000 CR3: 0000000033ed5000 CR4: 0000000000350ef0
Call Trace:
hrtimer_interrupt+0x45b/0xaa0 kernel/time/hrtimer.c:1903
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1045 [inline]
__sysvec_apic_timer_interrupt+0x102/0x3e0 arch/x86/kernel/apic/apic.c:1062
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline]
sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1056
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:preempt_schedule_irq+0x48/0xa0 kernel/sched/core.c:7190
Code: 49 be 00 00 00 00 00 fc ff df eb 09 48 f7 03 10 00 00 00 74 54 bf 01 00 00 00 e8 43 eb 35 f6 e8 ce fc 6d f6 fb bf 01 00 00 00 c3 a9 ff ff 9c 58 fa a9 00 02 00 00 74 05 e8 54 fe 6d f6 bf 01
RSP: 0018:ffffc90000087ae8 EFLAGS: 00000206
RAX: 000000000002008d RBX: 0000000000000000 RCX: 0000000000000001
RDX: 0000000000000000 RSI: ffffffff8d79201e RDI: 0000000000000001
RBP: 0000000000000000 R08: ffffffff8f822277 R09: 1ffffffff1f0444e
R10: dffffc0000000000 R11: fffffbfff1f0444f R12: 0000000000000000
R13: 0000000000000000 R14: dffffc0000000000 R15: 0000000000000000
irqentry_exit+0x5d8/0x660 kernel/entry/common.c:216
asm_sysvec_reschedule_ipi+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:lockdep_unregister_key+0x2ce/0x350 kernel/locking/lockdep.c:6616
Code: 41 5d 41 5e 41 5f 5d e9 00 f1 08 00 89 c7 e8 79 07 00 00 e9 6c fe ff ff e8 6f 5e bb 09 41 f7 c7 00 02 00 00 74 bb fb 40 84 ed <75> ba eb cb 90 0f 0b 90 e9 2e ff ff ff 90 0f 0b 90 e9 36 ff ff ff
RSP: 0018:ffffc90000087c08 EFLAGS: 00000246
RAX: 0000000000000046 RBX: ffff88807c648938 RCX: 0000000000000046
RDX: ffffffff9343c3d8 RSI: ffffffff8d7a6988 RDI: ffffffff8bc083e0
RBP: ffff88801befbd00 R08: ffffffff81ab3a98 R09: ffffffff8df41aa0
R10: dffffc0000000000 R11: fffffbfff1f0444f R12: 0000000000000000
R13: ffff88807c648939 R14: 0000000000001000 R15: 0000000000000a47
wq_unregister_lockdep kernel/workqueue.c:4852 [inline]
pwq_release_workfn+0x6d5/0x870 kernel/workqueue.c:5148
kthread_worker_fn+0x4f0/0xb20 kernel/kthread.c:1005
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x510/0xa50 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
rcu: rcu_preempt kthread starved for 10480 jiffies! g77821 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1
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:R running task stack:27712 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x149b/0x4fd0 kernel/sched/core.c:6863
__schedule_loop kernel/sched/core.c:6945 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6960
schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x301/0x1540 kernel/rcu/tree.c:2083
rcu_gp_kthread+0x99/0x390 kernel/rcu/tree.c:2285
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x510/0xa50 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
rcu: Stack dump where RCU GP kthread last ran:
CPU: 1 UID: 0 PID: 13324 Comm: udevd Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0x47/0x80 kernel/locking/spinlock.c:194
Code: f7 e8 0d 6b 42 f6 f7 c3 00 02 00 00 74 05 e8 50 95 6c f6 9c 58 a9 00 02 00 00 75 27 f7 c3 00 02 00 00 74 01 fb bf 01 00 00 00 44 85 34 f6 65 8b 05 4d e8 23 07 85 c0 74 18 5b 41 5e e9 1c 19
RSP: 0018:ffffc90000a08d88 EFLAGS: 00000206
RAX: 0000000000000002 RBX: 0000000000000246 RCX: 0000000000000102
RDX: 0000000000000002 RSI: ffffffff8d79201e RDI: 0000000000000001
RBP: ffffc90000a08ef0 R08: ffffffff8f822277 R09: 1ffffffff1f0444e
R10: dffffc0000000000 R11: fffffbfff1f0444f R12: ffff88805e73f0b8
R13: dffffc0000000000 R14: ffff8880b8728240 R15: 0000000000000001
FS: 00007efd04393880(0000) GS:ffff888125f1f000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f58e05efd58 CR3: 0000000033ed5000 CR4: 0000000000350ef0
Call Trace:
__run_hrtimer kernel/time/hrtimer.c:1773 [inline]
__hrtimer_run_queues+0x408/0xc30 kernel/time/hrtimer.c:1841
hrtimer_run_softirq+0x187/0x2b0 kernel/time/hrtimer.c:1858
handle_softirqs+0x22b/0x7c0 kernel/softirq.c:622
__do_softirq kernel/softirq.c:656 [inline]
invoke_softirq kernel/softirq.c:496 [inline]
__irq_exit_rcu+0x60/0x150 kernel/softirq.c:723
irq_exit_rcu+0x9/0x30 kernel/softirq.c:739
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline]
sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1056
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:csd_lock_wait kernel/smp.c:342 [inline]
RIP: 0010:smp_call_function_many_cond+0xcca/0x1260 kernel/smp.c:877
Code: 89 ee 83 e6 01 31 ff e8 d4 95 0b 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 7f 91 0b 00 eb 38 f3 90 42 0f b6 04 2b <84> c0 75 11 41 f7 04 24 01 00 00 00 74 1e e8 63 91 0b 00 eb e4 44
RSP: 0018:ffffc90004e67b40 EFLAGS: 00000293
RAX: 0000000000000000 RBX: 1ffff110170c856d RCX: ffff88802d568000
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc90004e67c68 R08: ffffffff8f822277 R09: 1ffffffff1f0444e
R10: dffffc0000000000 R11: fffffbfff1f0444f R12: ffff8880b8642b68
R13: dffffc0000000000 R14: ffff8880b873bb00 R15: 0000000000000000
on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1043
kill_bdev block/bdev.c:90 [inline]
blkdev_flush_mapping+0xff/0x2f0 block/bdev.c:729
blkdev_put_whole block/bdev.c:736 [inline]
bdev_release+0x417/0x650 block/bdev.c:1161
blkdev_release+0x15/0x20 block/fops.c:706
__fput+0x44c/0xa70 fs/file_table.c:468
fput_close_sync+0x113/0x220 fs/file_table.c:573
__do_sys_close fs/open.c:1573 [inline]
__se_sys_close fs/open.c:1558 [inline]
__x64_sys_close+0x7f/0x110 fs/open.c:1558
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xec/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7efd03ca7407
Code: 48 89 fa 4c 89 df e8 38 aa 00 00 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 1a 5b c3 0f 1f 84 00 00 00 00 00 48 8b 44 24 10 0f 05 <5b> c3 0f 1f 80 00 00 00 00 83 e2 39 83 fa 08 75 de e8 23 ff ff ff
RSP: 002b:00007ffd12ee3210 EFLAGS: 00000202 ORIG_RAX: 0000000000000003
RAX: ffffffffffffffda RBX: 00007efd04393880 RCX: 00007efd03ca7407
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000008
RBP: 00007efd043936e8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000002
R13: 000055c309787190 R14: 0000000000000008 R15: 000055c3097796d0