rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 1-...!: (10500 ticks this GP) idle=05d/1/0x4000000000000000 softirq=7310/7319 fqs=0
(t=10502 jiffies g=8657 q=175)
rcu: rcu_preempt kthread starved for 10503 jiffies! g8657 f0x0 RCU_GP_INIT(4) ->state=0x0 ->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:R running task stack:27008 pid: 15 ppid: 2 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5030 [inline]
__schedule+0x11b8/0x43b0 kernel/sched/core.c:6376
preempt_schedule_irq+0xb1/0x150 kernel/sched/core.c:6780
irqentry_exit+0x63/0x70 kernel/entry/common.c:432
asm_sysvec_reschedule_ipi+0x16/0x20 arch/x86/include/asm/idtentry.h:681
RIP: 0010:rcu_gp_fqs_check_wake kernel/rcu/tree.c:1890 [inline]
RIP: 0010:rcu_gp_fqs_loop+0x114/0x11b0 kernel/rcu/tree.c:1972
Code: 44 24 48 4c 89 64 24 50 48 89 d8 48 c1 e8 03 80 3c 10 00 74 12 48 89 df e8 39 91 58 00 48 ba 00 00 00 00 00 fc ff df 48 8b 1b <41> f6 c7 04 41 0f 94 c7 b0 01 eb 26 48 8b 05 c1 69 ad 0a 48 89 c3
RSP: 0018:ffffc90000d47cc0 EFLAGS: 00000246
RAX: 1ffffffff1823fbc RBX: 0000000000000001 RCX: 1ffff920001a8fb1
RDX: dffffc0000000000 RSI: ffffffff8a0b2260 RDI: ffffffff8a59a2c0
RBP: ffffc90000d47e10 R08: dffffc0000000000 R09: fffffbfff1824059
R10: fffffbfff1824059 R11: 1ffffffff1824058 R12: 1ffffffff17c1e30
R13: ffffc90000d47d88 R14: ffff88813feac100 R15: 0000000000000000
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:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 4329 Comm: syz.4.18 Not tainted 5.15.181-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/19/2025
RIP: 0010:__lock_acquire+0xed/0x7c60 kernel/locking/lockdep.c:4882
Code: 84 c0 0f 85 2f 65 00 00 83 3d 02 f7 0c 0c 00 0f 84 a8 27 00 00 83 3d 31 c9 a2 0a 00 74 29 48 89 d8 48 c1 e8 03 42 80 3c 00 00 <74> 12 48 89 df e8 b9 49 61 00 49 b8 00 00 00 00 00 fc ff df 48 81
RSP: 0018:ffffc900000078a0 EFLAGS: 00000046
RAX: 1ffffffff18237cc RBX: ffffffff8c11be60 RCX: 1ffff92000000f38
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff8c11be60
RBP: ffffc90000007af0 R08: dffffc0000000000 R09: 0000000000000001
R10: fffffbfff1ad155e R11: 1ffffffff1ad155d R12: 0000000000000000
R13: ffff888025b25940 R14: 0000000000000000 R15: 0000000000000001
FS: 00007f8eaed566c0(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c2728b1 CR3: 0000000077879000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
lock_acquire+0x197/0x3f0 kernel/locking/lockdep.c:5623
rcu_lock_acquire+0x2a/0x30 include/linux/rcupdate.h:312
rcu_read_lock include/linux/rcupdate.h:739 [inline]
send_sigqueue+0xd1/0x620 kernel/signal.c:1973
posix_timer_event kernel/time/posix-timers.c:359 [inline]
posix_timer_fn+0x16a/0x3d0 kernel/time/posix-timers.c:385
__run_hrtimer kernel/time/hrtimer.c:1690 [inline]
__hrtimer_run_queues+0x53d/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:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:169 [inline]
RIP: 0010:_raw_spin_unlock_irq+0x25/0x40 kernel/locking/spinlock.c:202
Code: f6 ff 0f 1f 00 53 48 89 fb 48 83 c7 18 48 8b 74 24 08 e8 4e d6 b1 f7 48 89 df e8 16 ab b2 f7 e8 71 4f d3 f7 fb bf 01 00 00 00 46 cf a6 f7 65 8b 05 e7 e2 57 76 85 c0 74 02 5b c3 e8 94 ed 55
RSP: 0018:ffffc9000304fbc0 EFLAGS: 00000282
RAX: 3f0a87aa32035d00 RBX: ffff888076ffef00 RCX: 3f0a87aa32035d00
RDX: dffffc0000000000 RSI: ffffffff8a0b0fc0 RDI: 0000000000000001
RBP: 0000000000000000 R08: dffffc0000000000 R09: ffffed100edffde1
R10: ffffed100edffde1 R11: 1ffff1100edffde0 R12: ffff888076ffef00
R13: 0000000000000021 R14: dffffc0000000000 R15: 000000001c000004
spin_unlock_irq include/linux/spinlock.h:413 [inline]
get_signal+0x11d6/0x12c0 kernel/signal.c:2903
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: 0033:0x7f8eb0eee967
Code: ff ff 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
RSP: 002b:00007f8eaed560e8 EFLAGS: 00000246
RAX: 00000000000000ca RBX: 00007f8eb1115fa8 RCX: 00007f8eb0eee969
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f8eb1115fa8
RBP: 00007f8eb1115fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f8eb1115fac
R13: 0000000000000000 R14: 00007ffefd0f86b0 R15: 00007ffefd0f8798
NMI backtrace for cpu 1
CPU: 1 PID: 4326 Comm: syz.3.17 Not tainted 5.15.181-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/19/2025
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_dump_cpu_stacks+0x22f/0x380 kernel/rcu/tree_stall.h:349
print_cpu_stall+0x31d/0x5f0 kernel/rcu/tree_stall.h:633
check_cpu_stall kernel/rcu/tree_stall.h:727 [inline]
rcu_pending kernel/rcu/tree.c:3932 [inline]
rcu_sched_clock_irq+0x6d8/0x1110 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:lock_acquire+0x1f2/0x3f0 kernel/locking/lockdep.c:5627
Code: 00 9c 8f 84 24 80 00 00 00 f6 84 24 81 00 00 00 02 0f 85 f6 00 00 00 41 f7 c6 00 02 00 00 74 01 fb 48 c7 44 24 60 0e 36 e0 45 <4b> c7 44 3d 00 00 00 00 00 66 43 c7 44 3d 09 00 00 43 c6 44 3d 0b
RSP: 0018:ffffc90002f9fb00 EFLAGS: 00000206
RAX: 0000000000000001 RBX: 0000000000000000 RCX: caa7d79ebb0c7500
RDX: 0000000000000000 RSI: ffffffff8a0b2260 RDI: ffffffff8a59a2c0
RBP: ffffc90002f9fc20 R08: dffffc0000000000 R09: fffffbfff1ff321f
R10: fffffbfff1ff321f R11: 1ffffffff1ff321e R12: ffff8880234e6a28
R13: 1ffff920005f3f6c R14: 0000000000000246 R15: dffffc0000000000
__might_fault+0xb3/0x110 mm/memory.c:5357
_copy_to_user+0x29/0x130 lib/usercopy.c:35
copy_to_user include/linux/uaccess.h:200 [inline]
copy_siginfo_to_user+0x20/0x80 kernel/signal.c:3367
__setup_rt_frame arch/x86/kernel/signal.c:490 [inline]
setup_rt_frame arch/x86/kernel/signal.c:780 [inline]
handle_signal arch/x86/kernel/signal.c:824 [inline]
arch_do_signal_or_restart+0xd56/0x1300 arch/x86/kernel/signal.c:869
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: 0033:0x7fee4864b967
Code: ff ff 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
RSP: 002b:00007fee464920e8 EFLAGS: 00000246
RAX: 00000000000000ca RBX: 00007fee48873088 RCX: 00007fee4864b969
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007fee48873088
RBP: 00007fee48873080 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fee4887308c
R13: 0000000000000000 R14: 00007fffb155fea0 R15: 00007fffb155ff88