rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 0-...!: (1 GPs behind) idle=585/1/0x4000000000000000 softirq=9100/9101 fqs=17
(detected by 1, t=10502 jiffies, g=10625, q=585)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 4866 Comm: syz.4.154 Not tainted 5.15.184-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:debug_spin_unlock kernel/locking/spinlock_debug.c:101 [inline]
RIP: 0010:do_raw_spin_unlock+0x77/0x230 kernel/locking/spinlock_debug.c:140
Code: c1 e8 03 42 0f b6 04 20 84 c0 0f 85 6f 01 00 00 83 3b 00 0f 84 e5 00 00 00 4c 8d 73 10 4d 89 f5 49 c1 ed 03 43 80 7c 25 00 00 <74> 08 4c 89 f7 e8 7f fb 5f 00 65 48 8b 05 27 34 a5 7e 49 39 06 0f
RSP: 0018:ffffc90000007bc8 EFLAGS: 00000046
RAX: 0000000000000000 RBX: ffffffff962dc218 RCX: ffffffff815d3b59
RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffffffff962dc218
RBP: ffffc90000007c80 R08: dffffc0000000000 R09: fffffbfff2c5b844
R10: fffffbfff2c5b844 R11: 1ffffffff2c5b843 R12: dffffc0000000000
R13: 1ffffffff2c5b845 R14: ffffffff962dc228 R15: 1ffff92000000f80
FS: 00007ff8b606d6c0(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b3081eff8 CR3: 000000007775e000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000080000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:159 [inline]
_raw_spin_unlock_irqrestore+0x75/0x100 kernel/locking/spinlock.c:194
debug_object_activate+0x2d2/0x480 lib/debugobjects.c:712
debug_hrtimer_activate kernel/time/hrtimer.c:410 [inline]
debug_activate kernel/time/hrtimer.c:465 [inline]
enqueue_hrtimer+0x30/0x370 kernel/time/hrtimer.c:1074
__run_hrtimer kernel/time/hrtimer.c:1707 [inline]
__hrtimer_run_queues+0x65a/0xc40 kernel/time/hrtimer.c:1754
hrtimer_interrupt+0x3bb/0x8d0 kernel/time/hrtimer.c:1816
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1097 [inline]
__sysvec_apic_timer_interrupt+0x137/0x4a0 arch/x86/kernel/apic/apic.c:1114
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline]
sysvec_apic_timer_interrupt+0x9b/0xc0 arch/x86/kernel/apic/apic.c:1108
asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:__sanitizer_cov_trace_pc+0x41/0x60 kernel/kcov.c:211
Code: ff 00 74 11 81 fa 00 01 00 00 75 35 83 b9 34 16 00 00 00 74 2c 8b 91 10 16 00 00 83 fa 02 75 21 48 8b 91 18 16 00 00 48 8b 32 <48> 8d 7e 01 8b 89 14 16 00 00 48 39 cf 73 08 48 89 44 f2 08 48 89
RSP: 0018:ffffc9000137fa98 EFLAGS: 00000246
RAX: ffffffff87c5bcf4 RBX: 0000000000000000 RCX: ffff88802ad81dc0
RDX: ffffc9000f29e000 RSI: 000000000007ffff RDI: 0000000000000080
RBP: ffffc9000137fc90 R08: 0000000000000000 R09: fffff5200026ff67
R10: fffff5200026ff67 R11: 1ffff9200026ff60 R12: ffffc9000137fd40
R13: dffffc0000000000 R14: 1ffff9200026ffa9 R15: 1ffff9200026ff5c
__copy_msghdr_from_user net/socket.c:2333 [inline]
copy_msghdr_from_user net/socket.c:2369 [inline]
recvmsg_copy_msghdr net/socket.c:2621 [inline]
___sys_recvmsg+0x2e4/0x4f0 net/socket.c:2693
do_recvmmsg+0x344/0x7a0 net/socket.c:2791
__sys_recvmmsg net/socket.c:2870 [inline]
__do_sys_recvmmsg net/socket.c:2893 [inline]
__se_sys_recvmmsg net/socket.c:2886 [inline]
__x64_sys_recvmmsg+0x18d/0x240 net/socket.c:2886
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7ff8b8226969
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ff8b606d038 EFLAGS: 00000246 ORIG_RAX: 000000000000012b
RAX: ffffffffffffffda RBX: 00007ff8b844e080 RCX: 00007ff8b8226969
RDX: 0000000000010106 RSI: 00002000000000c0 RDI: 0000000000000003
RBP: 00007ff8b82a8ab1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007ff8b844e080 R15: 00007ffd667e8458
rcu: rcu_preempt kthread starved for 9286 jiffies! g10625 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:27464 pid: 15 ppid: 2 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5030 [inline]
__schedule+0x11b8/0x43b0 kernel/sched/core.c:6376
schedule+0x11b/0x1e0 kernel/sched/core.c:6459
schedule_timeout+0x15c/0x280 kernel/time/timer.c:1914
rcu_gp_fqs_loop+0x29e/0x11b0 kernel/rcu/tree.c:1972
rcu_gp_kthread+0x98/0x350 kernel/rcu/tree.c:2145
kthread+0x436/0x520 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
rcu: Stack dump where RCU GP kthread last ran:
NMI backtrace for cpu 1
CPU: 1 PID: 4814 Comm: syz.2.143 Not tainted 5.15.184-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Call Trace:
dump_stack_lvl+0x168/0x230 lib/dump_stack.c:106
nmi_cpu_backtrace+0x397/0x3d0 lib/nmi_backtrace.c:111
nmi_trigger_cpumask_backtrace+0x163/0x280 lib/nmi_backtrace.c:62
trigger_single_cpu_backtrace include/linux/nmi.h:166 [inline]
rcu_check_gp_kthread_starvation+0x1cd/0x250 kernel/rcu/tree_stall.h:487
print_other_cpu_stall+0x10c8/0x1220 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+0x831/0x1110 kernel/rcu/tree.c:2619
update_process_times+0x193/0x200 kernel/time/timer.c:1818
tick_sched_handle kernel/time/tick-sched.c:254 [inline]
tick_sched_timer+0x37d/0x560 kernel/time/tick-sched.c:1473
__run_hrtimer kernel/time/hrtimer.c:1690 [inline]
__hrtimer_run_queues+0x4fe/0xc40 kernel/time/hrtimer.c:1754
hrtimer_interrupt+0x3bb/0x8d0 kernel/time/hrtimer.c:1816
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1097 [inline]
__sysvec_apic_timer_interrupt+0x137/0x4a0 arch/x86/kernel/apic/apic.c:1114
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline]
sysvec_apic_timer_interrupt+0x9b/0xc0 arch/x86/kernel/apic/apic.c:1108
asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:csd_lock_wait kernel/smp.c:440 [inline]
RIP: 0010:smp_call_function_many_cond+0xb88/0xd70 kernel/smp.c:969
Code: b6 44 05 00 84 c0 0f 85 9d 00 00 00 41 8b 1c 24 89 de 83 e6 01 31 ff e8 a6 55 0b 00 83 e3 01 75 07 e8 3c 52 0b 00 eb 43 f3 90 <48> b8 00 00 00 00 00 fc ff df 41 0f b6 44 05 00 84 c0 75 11 41 f7
RSP: 0018:ffffc900014ef680 EFLAGS: 00000293
RAX: ffffffff816c6f2b RBX: 0000000000000001 RCX: ffff88802a310000
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc900014ef7c0 R08: dffffc0000000000 R09: fffffbfff1ff3624
R10: fffffbfff1ff3624 R11: 1ffffffff1ff3623 R12: ffff8880b9042a08
R13: 1ffff11017208541 R14: ffff8880b913b380 R15: 0000000000000000
on_each_cpu_cond_mask+0x3b/0x80 kernel/smp.c:1135
kill_bdev block/bdev.c:76 [inline]
blkdev_flush_mapping+0x178/0x340 block/bdev.c:659
blkdev_put_whole block/bdev.c:690 [inline]
blkdev_put+0x4d1/0x7d0 block/bdev.c:957
blkdev_close+0x76/0xa0 block/fops.c:478
__fput+0x234/0x930 fs/file_table.c:311
task_work_run+0x125/0x1a0 kernel/task_work.c:188
exit_task_work include/linux/task_work.h:33 [inline]
do_exit+0x616/0x20a0 kernel/exit.c:874
do_group_exit+0x12e/0x300 kernel/exit.c:996
get_signal+0x6ca/0x12c0 kernel/signal.c:2900
arch_do_signal_or_restart+0xc1/0x1300 arch/x86/kernel/signal.c:867
handle_signal_work kernel/entry/common.c:154 [inline]
exit_to_user_mode_loop+0x9e/0x130 kernel/entry/common.c:178
exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:214
__syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline]
syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:307
do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f562c1dd969
Code: Unable to access opcode bytes at RIP 0x7f562c1dd93f.
RSP: 002b:00007f562a045038 EFLAGS: 00000246 ORIG_RAX: 0000000000000028
RAX: 0000000000076000 RBX: 00007f562c404fa0 RCX: 00007f562c1dd969
RDX: 0000000000000000 RSI: 0000000000000005 RDI: 0000000000000004
RBP: 00007f562c25fab1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000fffe82 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f562c404fa0 R15: 00007ffe319772c8