rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 0-...!: (10488 ticks this GP) idle=40a4/1/0x4000000000000000 softirq=11152/11152 fqs=6
(t=10500 jiffies g=11641 q=60 ncpus=2)
rcu: rcu_preempt kthread starved for 10485 jiffies! g11641 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:27200 pid:16 ppid:2 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5244 [inline]
__schedule+0x10ec/0x40b0 kernel/sched/core.c:6561
schedule+0xb9/0x180 kernel/sched/core.c:6637
schedule_timeout+0x15c/0x280 kernel/time/timer.c:1965
rcu_gp_fqs_loop+0x2f2/0x1310 kernel/rcu/tree.c:1706
rcu_gp_kthread+0x95/0x380 kernel/rcu/tree.c:1905
kthread+0x29d/0x330 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 4627 Comm: syz.3.60 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
RIP: 0010:__lock_acquire+0xfea/0x7c50 kernel/locking/lockdep.c:-1
Code: 8b 7c 24 40 e8 07 f5 6d 00 eb bb 44 89 e0 25 ff 1f 00 00 41 c1 ec 03 41 81 e4 00 60 00 00 41 09 c4 4c 89 ee 48 c1 ee 20 89 f0 c0 04 41 29 f4 44 31 e0 44 01 ee 41 29 c5 89 c1 c1 c1 06 44 31
RSP: 0018:ffffc900001e09c0 EFLAGS: 00000807
RAX: 00000000abe92a66 RBX: 0000000000020016 RCX: ffffffff816304f6
RDX: 0000000000000000 RSI: 00000000abe92a66 RDI: ffffffff90ae2248
RBP: ffffc900001e0c10 R08: dffffc0000000000 R09: fffffbfff215c44a
R10: fffffbfff215c44a R11: 1ffffffff215c449 R12: 0000000000004048
R13: abe92a66ad81a2ce R14: ffff88802b486420 R15: ffff88802b486468
FS: 00007fc6160246c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000020000006b000 CR3: 0000000055fea000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
lock_acquire+0x1b4/0x490 kernel/locking/lockdep.c:5662
seqcount_lockdep_reader_access+0xc6/0x1c0 include/linux/seqlock.h:102
timekeeping_get_delta kernel/time/timekeeping.c:254 [inline]
timekeeping_get_ns kernel/time/timekeeping.c:388 [inline]
ktime_get_update_offsets_now+0x95/0x3e0 kernel/time/timekeeping.c:2320
hrtimer_update_base kernel/time/hrtimer.c:659 [inline]
hrtimer_interrupt+0x130/0x9c0 kernel/time/hrtimer.c:1855
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1107 [inline]
__sysvec_apic_timer_interrupt+0x153/0x5a0 arch/x86/kernel/apic/apic.c:1124
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1118 [inline]
sysvec_apic_timer_interrupt+0x9b/0xc0 arch/x86/kernel/apic/apic.c:1118
asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691
RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:160 [inline]
RIP: 0010:_raw_spin_unlock_irq+0x25/0x40 kernel/locking/spinlock.c:202
Code: f5 ff 0f 1f 00 53 48 89 fb 48 83 c7 18 48 8b 74 24 08 e8 6e c8 41 f7 48 89 df e8 c6 8d 42 f7 e8 f1 7f 65 f7 fb bf 01 00 00 00 16 0b 36 f7 65 8b 05 17 c4 e0 75 85 c0 74 02 5b c3 e8 64 d5 de
RSP: 0018:ffffc9000520fbb8 EFLAGS: 00000286
RAX: 3967132657fefe00 RBX: ffff88801cfb3780 RCX: 3967132657fefe00
RDX: dffffc0000000000 RSI: ffffffff8a8c0500 RDI: 0000000000000001
RBP: ffff88801cfb3c18 R08: dffffc0000000000 R09: ffffed10039f66f1
R10: ffffed10039f66f1 R11: 1ffff110039f66f0 R12: 1ffff110039f6783
R13: 0000000000000021 R14: dffffc0000000000 R15: 0000000000000000
spin_unlock_irq include/linux/spinlock.h:401 [inline]
get_signal+0x1163/0x1350 kernel/signal.c:2874
arch_do_signal_or_restart+0xb0/0x1230 arch/x86/kernel/signal.c:871
exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174
exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210
__syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline]
syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:303
do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:87
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fc61518eec7
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:00007fc616024038 EFLAGS: 00000246
RAX: 0000000000000113 RBX: 00007fc6153e5fa0 RCX: 00007fc61518eec9
RDX: 0000000000000008 RSI: 0000000000000000 RDI: 0000000000000006
RBP: 00007fc615211f91 R08: 00000000000000a4 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fc6153e6038 R14: 00007fc6153e5fa0 R15: 00007fff35e4a538
CPU: 0 PID: 4630 Comm: syz.2.62 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:160 [inline]
RIP: 0010:_raw_spin_unlock_irq+0x25/0x40 kernel/locking/spinlock.c:202
Code: f5 ff 0f 1f 00 53 48 89 fb 48 83 c7 18 48 8b 74 24 08 e8 6e c8 41 f7 48 89 df e8 c6 8d 42 f7 e8 f1 7f 65 f7 fb bf 01 00 00 00 16 0b 36 f7 65 8b 05 17 c4 e0 75 85 c0 74 02 5b c3 e8 64 d5 de
RSP: 0018:ffffc9000516fbb8 EFLAGS: 00000286
RAX: f34b8486243d7a00 RBX: ffff88801cfb2500 RCX: f34b8486243d7a00
RDX: dffffc0000000000 RSI: ffffffff8a8c0500 RDI: 0000000000000001
RBP: ffff88801cfb2998 R08: dffffc0000000000 R09: ffffed10039f64a1
R10: ffffed10039f64a1 R11: 1ffff110039f64a0 R12: 1ffff110039f6533
R13: 0000000000000021 R14: dffffc0000000000 R15: 0000000000000000
FS: 00007fc1505bd6c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c3fa601 CR3: 00000000780a0000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
spin_unlock_irq include/linux/spinlock.h:401 [inline]
get_signal+0x1163/0x1350 kernel/signal.c:2874
arch_do_signal_or_restart+0xb0/0x1230 arch/x86/kernel/signal.c:871
exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174
exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210
__syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline]
syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:303
do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:87
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fc14f78eec7
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:00007fc1505bd0e8 EFLAGS: 00000246
RAX: 00000000000000ca RBX: 00007fc14f9e5fa8 RCX: 00007fc14f78eec9
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007fc14f9e5fa8
RBP: 00007fc14f9e5fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fc14f9e6038 R14: 00007ffc87636b00 R15: 00007ffc87636be8
sched: RT throttling activated