rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 1-...!: (10500 ticks this GP) idle=113c/1/0x4000000000000000 softirq=11387/11387 fqs=0
(t=10502 jiffies g=10941 q=121 ncpus=2)
rcu: rcu_preempt kthread timer wakeup didn't happen for 10502 jiffies! g10941 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: Possible timer handling issue on cpu=0 timer-softirq=10905
rcu: rcu_preempt kthread starved for 10505 jiffies! g10941 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:27840 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:2167
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 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 4513 Comm: syz.4.21 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
RIP: 0010:native_irq_disable arch/x86/include/asm/irqflags.h:40 [inline]
RIP: 0010:arch_local_irq_disable arch/x86/include/asm/irqflags.h:75 [inline]
RIP: 0010:arch_local_irq_save arch/x86/include/asm/irqflags.h:107 [inline]
RIP: 0010:__local_bh_disable_ip+0x92/0x190 kernel/softirq.c:348
Code: c6 44 3c 0b f3 65 8b 05 24 00 b4 7e a9 00 00 0f 00 0f 85 df 00 00 00 48 c7 44 24 40 00 00 00 00 9c 8f 44 24 40 4c 8b 74 24 40 65 01 1d fe ff b3 7e 65 8b 05 f7 ff b3 7e 31 d8 a9 00 ff 00 00
RSP: 0018:ffffc90003627ba0 EFLAGS: 00000246
RAX: 0000000080000000 RBX: 0000000000000200 RCX: ffff888025e05940
RDX: 0000000000000000 RSI: 0000000000000200 RDI: ffffffff812f16d6
RBP: ffffc90003627c58 R08: 0000000000000000 R09: fffff520006c4f72
R10: fffff520006c4f72 R11: 1ffff920006c4f6c R12: 1ffff920006c4f74
R13: 1ffff920006c4fff R14: 0000000000000246 R15: dffffc0000000000
FS: 000055556216f500(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 00000000284d0000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
local_bh_disable include/linux/bottom_half.h:20 [inline]
fpregs_lock arch/x86/include/asm/fpu/api.h:72 [inline]
fpu__clear_user_states+0x43/0x260 arch/x86/kernel/fpu/core.c:711
handle_signal arch/x86/kernel/signal.c:844 [inline]
arch_do_signal_or_restart+0xeb0/0x1240 arch/x86/kernel/signal.c:873
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: 0033:0x7fe1bf84d6e0
Code: 44 24 20 0f 29 44 24 30 0f 29 44 24 40 48 8b 44 24 08 ff d0 48 83 c4 50 31 c0 5b 5d 41 5c 41 5d 41 5e c3 0f 1f 80 00 00 00 00 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 c3 66 66 2e 0f 1f
RSP: 002b:00007fff9ab2e678 EFLAGS: 00000203
RAX: 0000000000000000 RBX: 00007fe1bfbe5fa0 RCX: 00007fe1bfa13f91
RDX: 00007fff9ab2e680 RSI: 00007fff9ab2e7b0 RDI: 0000000000000011
RBP: 00007fe1bfa13f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fe1bfbe5fa0 R14: 00007fe1bfbe5fa0 R15: 0000000000000004
CPU: 1 PID: 4512 Comm: syz.3.27 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
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 8e 8f 41 f7 48 89 df e8 e6 54 42 f7 e8 31 48 65 f7 fb bf 01 00 00 00 76 cd 35 f7 65 8b 05 f7 84 e0 75 85 c0 74 02 5b c3 e8 44 96 de
RSP: 0018:ffffc90003617b98 EFLAGS: 00000282
RAX: 17da008646f02d00 RBX: ffff88801eb52500 RCX: 17da008646f02d00
RDX: dffffc0000000000 RSI: ffffffff8a8c0580 RDI: 0000000000000001
RBP: ffff88801eb52798 R08: dffffc0000000000 R09: ffffed1003d6a4a1
R10: ffffed1003d6a4a1 R11: 1ffff11003d6a4a0 R12: 1ffff11003d6a4f3
R13: 0000000000000011 R14: dffffc0000000000 R15: 0000000000000000
FS: 000055555c330500(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 00000000576a0000 CR4: 00000000003506e0
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+0xb7/0x1240 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: 0033:0x7fb47d45ee7e
Code: 00 4c 8b 34 24 49 89 d8 48 ba db 34 b6 d7 82 de 1b 43 48 89 d0 48 f7 64 24 58 48 8d 3d 13 65 1b 00 31 c0 41 8b 36 48 c1 ea 12 <48> 01 ca 48 89 e9 48 2b 15 5d 68 eb 00 e8 e0 f0 fe ff 49 83 be 88
RSP: 002b:00007ffd898d1600 EFLAGS: 00000202
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 000000000003bd08
RDX: 00000000000001ea RSI: 0000000000000000 RDI: 00007fb47d615388
RBP: 00007fb47d62d196 R08: 0000000000000000 R09: 001d2f1e191c63d6
R10: 0000007fbd68ffb7 R11: 0000000000009cf4 R12: 0000000000000000
R13: 00007fb47d7e5fa0 R14: 00007fb47d7e5fa0 R15: 0000000000000004