rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 0-...!: (1 GPs behind) idle=8a6c/1/0x4000000000000000 softirq=31138/31141 fqs=1
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P5866/1:b..l
rcu: (detected by 1, t=10502 jiffies, g=23265, q=363 ncpus=2)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 7796 Comm: syz.3.401 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:rcu_is_watching+0x67/0xb0 kernel/rcu/tree.c:752
Code: 89 f7 e8 ec e6 7d 00 48 c7 c3 98 af c4 92 49 03 1e 48 89 d8 48 c1 e8 03 42 0f b6 04 38 84 c0 75 34 8b 03 65 ff 0d 79 29 1d 11 <74> 11 83 e0 04 c1 e8 02 5b 41 5e 41 5f e9 97 93 df 09 cc e8 a1 71
RSP: 0018:ffffc90000007b20 EFLAGS: 00000006
RAX: 0000000000428a6c RBX: ffff8880b8632f98 RCX: 65268493fe539d00
RDX: 0000000000000000 RSI: ffffffff8c036ee0 RDI: ffffffff8c036ea0
RBP: ffffffff84d4b10b R08: 0000000000000001 R09: 0000000000000000
R10: ffffc90000007ca0 R11: fffff52000000f96 R12: 0000000000000000
R13: ffffffff99f6f600 R14: ffffffff8dde6dd0 R15: dffffc0000000000
FS: 00007f11fce816c0(0000) GS:ffff8881259e8000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c3b2a7d CR3: 000000005822c000 CR4: 00000000003526f0
Call Trace:
trace_lock_acquire include/trace/events/lock.h:24 [inline]
lock_acquire+0x5f/0x360 kernel/locking/lockdep.c:5831
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
_raw_spin_lock_irqsave+0xa7/0xf0 kernel/locking/spinlock.c:162
debug_object_activate+0xbb/0x420 lib/debugobjects.c:818
debug_hrtimer_activate kernel/time/hrtimer.c:438 [inline]
debug_activate kernel/time/hrtimer.c:477 [inline]
enqueue_hrtimer+0x30/0x3a0 kernel/time/hrtimer.c:1081
__run_hrtimer kernel/time/hrtimer.c:1794 [inline]
__hrtimer_run_queues+0x656/0xc60 kernel/time/hrtimer.c:1841
hrtimer_interrupt+0x45b/0xaa0 kernel/time/hrtimer.c:1903
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1041 [inline]
__sysvec_apic_timer_interrupt+0x10b/0x410 arch/x86/kernel/apic/apic.c:1058
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1052 [inline]
sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1052
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0xa8/0x110 kernel/locking/spinlock.c:194
Code: 74 05 e8 9b c9 41 f6 48 c7 44 24 20 00 00 00 00 9c 8f 44 24 20 f6 44 24 21 02 75 4f f7 c3 00 02 00 00 74 01 fb bf 01 00 00 00 03 64 0a f6 65 8b 05 fc e2 3d 07 85 c0 74 40 48 c7 04 24 0e 36
RSP: 0018:ffffc90016b9fb60 EFLAGS: 00000206
RAX: 65268493fe539d00 RBX: 0000000000000a06 RCX: 65268493fe539d00
RDX: 0000000000000007 RSI: ffffffff8dbbd648 RDI: 0000000000000001
RBP: ffffc90016b9fbf0 R08: ffffffff8fc3f337 R09: 1ffffffff1f87e66
R10: dffffc0000000000 R11: fffffbfff1f87e67 R12: dffffc0000000000
R13: ffff8880b8627a80 R14: ffff8880b8627a80 R15: 1ffff92002d73f6c
clock_was_set+0x63b/0x7c0 kernel/time/hrtimer.c:965
do_settimeofday64+0x41d/0x630 kernel/time/timekeeping.c:1460
__do_sys_clock_settime kernel/time/posix-timers.c:1131 [inline]
__se_sys_clock_settime kernel/time/posix-timers.c:1115 [inline]
__x64_sys_clock_settime+0x22c/0x280 kernel/time/posix-timers.c:1115
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f11fbf8eba9
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:00007f11fce81038 EFLAGS: 00000246 ORIG_RAX: 00000000000000e3
RAX: ffffffffffffffda RBX: 00007f11fc1d5fa0 RCX: 00007f11fbf8eba9
RDX: 0000000000000000 RSI: 0000200000000240 RDI: 0000000000000000
RBP: 00007f11fc011e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f11fc1d6038 R14: 00007f11fc1d5fa0 R15: 00007ffff01d2658
task:syz-executor state:R running task stack:21256 pid:5866 tgid:5866 ppid:5854 task_flags:0x400140 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5360 [inline]
__schedule+0x1798/0x4cc0 kernel/sched/core.c:6964
preempt_schedule_common+0x83/0xd0 kernel/sched/core.c:7148
preempt_schedule+0xae/0xc0 kernel/sched/core.c:7172
preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12
__raw_spin_unlock include/linux/spinlock_api_smp.h:143 [inline]
_raw_spin_unlock+0x3f/0x50 kernel/locking/spinlock.c:186
spin_unlock include/linux/spinlock.h:391 [inline]
copy_pte_range mm/memory.c:1330 [inline]
copy_pmd_range+0x7630/0x7f00 mm/memory.c:1390
copy_pud_range mm/memory.c:1427 [inline]
copy_p4d_range mm/memory.c:1451 [inline]
copy_page_range+0xc14/0x1270 mm/memory.c:1539
dup_mmap+0xf4f/0x1ab0 mm/mmap.c:1834
dup_mm kernel/fork.c:1504 [inline]
copy_mm+0x13c/0x4b0 kernel/fork.c:1556
copy_process+0x1706/0x3c00 kernel/fork.c:2196
kernel_clone+0x21e/0x840 kernel/fork.c:2624
__do_sys_clone kernel/fork.c:2765 [inline]
__se_sys_clone kernel/fork.c:2749 [inline]
__x64_sys_clone+0x18b/0x1e0 kernel/fork.c:2749
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f62d4d85413
RSP: 002b:00007fff22af5858 EFLAGS: 00000246 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f62d4d85413
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011
RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000001
R10: 000055555db267d0 R11: 0000000000000246 R12: 0000000000000000
R13: 00000000000927c0 R14: 000000000003ca0b R15: 00007fff22af59f0
rcu: rcu_preempt kthread starved for 10500 jiffies! g23265 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:27296 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5360 [inline]
__schedule+0x1798/0x4cc0 kernel/sched/core.c:6964
__schedule_loop kernel/sched/core.c:7046 [inline]
schedule+0x165/0x360 kernel/sched/core.c:7061
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+0x4bc/0x870 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
rcu: Stack dump where RCU GP kthread last ran:
CPU: 1 UID: 0 PID: 5859 Comm: syz-executor Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:csd_lock_wait kernel/smp.c:342 [inline]
RIP: 0010:smp_call_function_many_cond+0xd33/0x12d0 kernel/smp.c:877
Code: 45 8b 2c 24 44 89 ee 83 e6 01 31 ff e8 16 7c 0b 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 c1 77 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 a5 77
RSP: 0018:ffffc9000421f540 EFLAGS: 00000293
RAX: ffffffff81b443cb RBX: 1ffff110170c8355 RCX: ffff88802a050000
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc9000421f6c0 R08: ffffffff8fc3f337 R09: 1ffffffff1f87e66
R10: dffffc0000000000 R11: fffffbfff1f87e67 R12: ffff8880b8641aa8
R13: dffffc0000000000 R14: ffff8880b873b1c0 R15: 0000000000000000
FS: 00005555934ce500(0000) GS:ffff888125ae8000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fb960dad000 CR3: 00000000288d2000 CR4: 00000000003526f0
Call Trace:
on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1044
__flush_tlb_multi arch/x86/include/asm/paravirt.h:91 [inline]
flush_tlb_multi arch/x86/mm/tlb.c:1361 [inline]
flush_tlb_mm_range+0x6b1/0x12d0 arch/x86/mm/tlb.c:1451
dup_mmap+0x1598/0x1ab0 mm/mmap.c:1873
dup_mm kernel/fork.c:1504 [inline]
copy_mm+0x13c/0x4b0 kernel/fork.c:1556
copy_process+0x1706/0x3c00 kernel/fork.c:2196
kernel_clone+0x21e/0x840 kernel/fork.c:2624
__do_sys_clone kernel/fork.c:2765 [inline]
__se_sys_clone kernel/fork.c:2749 [inline]
__x64_sys_clone+0x18b/0x1e0 kernel/fork.c:2749
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f46c7f85413
Code: 1f 84 00 00 00 00 00 64 48 8b 04 25 10 00 00 00 45 31 c0 31 d2 31 f6 bf 11 00 20 01 4c 8d 90 d0 02 00 00 b8 38 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 35 89 c2 85 c0 75 2c 64 48 8b 04 25 10 00 00
RSP: 002b:00007ffe710cf978 EFLAGS: 00000246 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f46c7f85413
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011
RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000001
R10: 00005555934ce7d0 R11: 0000000000000246 R12: 0000000000000000
R13: 00000000000927c0 R14: 000000000003c9f8 R15: 00007ffe710cfb10