rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 0-...!: (1 GPs behind) idle=224c/1/0x4000000000000000 softirq=132263/132264 fqs=0
rcu: (detected by 1, t=10506 jiffies, g=125141, q=328 ncpus=2)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 22215 Comm: syz.1.4447 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:bytes_is_nonzero mm/kasan/generic.c:98 [inline]
RIP: 0010:memory_is_nonzero mm/kasan/generic.c:115 [inline]
RIP: 0010:memory_is_poisoned_n mm/kasan/generic.c:140 [inline]
RIP: 0010:memory_is_poisoned mm/kasan/generic.c:172 [inline]
RIP: 0010:check_region_inline mm/kasan/generic.c:191 [inline]
RIP: 0010:kasan_check_range+0x9f/0x2c0 mm/kasan/generic.c:200
Code: 00 fc ff df 4d 8d 34 19 4d 89 f4 4d 29 dc 49 83 fc 10 7f 29 4d 85 e4 0f 84 41 01 00 00 4c 89 cb 48 f7 d3 4c 01 fb 41 80 3b 00 <0f> 85 de 01 00 00 49 ff c3 48 ff c3 75 ee e9 21 01 00 00 44 89 dd
RSP: 0018:ffffc90000007cd0 EFLAGS: 00000046
RAX: ffffffff81af7501 RBX: ffffffffffffffff RCX: ffffffff81af7577
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff8f7deb70
RBP: 0000000000000000 R08: ffffffff8f7deb77 R09: 1ffffffff1efbd6e
R10: dffffc0000000000 R11: fffffbfff1efbd6e R12: 0000000000000001
R13: 0000000000000000 R14: fffffbfff1efbd6f R15: 1ffffffff1efbd6e
FS: 00007f88c155d6c0(0000) GS:ffff888125eba000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b3101cff8 CR3: 00000000217d4000 CR4: 00000000003526f0
Call Trace:
instrument_atomic_read include/linux/instrumented.h:68 [inline]
_test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline]
cpumask_test_cpu include/linux/cpumask.h:647 [inline]
cpu_online include/linux/cpumask.h:1227 [inline]
trace_hrtimer_start include/trace/events/timer.h:222 [inline]
debug_activate kernel/time/hrtimer.c:478 [inline]
enqueue_hrtimer+0x77/0x3a0 kernel/time/hrtimer.c:1081
__run_hrtimer kernel/time/hrtimer.c:1794 [inline]
__hrtimer_run_queues+0x636/0xc70 kernel/time/hrtimer.c:1841
hrtimer_interrupt+0x45b/0xaa0 kernel/time/hrtimer.c:1903
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1045 [inline]
__sysvec_apic_timer_interrupt+0x102/0x410 arch/x86/kernel/apic/apic.c:1062
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline]
sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1056
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:finish_task_switch+0x242/0x960 kernel/sched/core.c:5115
Code: 0f 84 84 01 00 00 48 85 db 0f 85 ab 01 00 00 e9 64 05 00 00 4c 8b 75 d0 4c 89 e7 e8 08 41 cc 09 e8 43 82 37 00 fb 4c 8b 65 c0 <49> 8d bc 24 48 16 00 00 48 89 f8 48 c1 e8 03 42 0f b6 04 28 84 c0
RSP: 0018:ffffc9000bd8f758 EFLAGS: 00000282
RAX: f82a950df549d400 RBX: 0000000000000000 RCX: f82a950df549d400
RDX: 0000000000000000 RSI: ffffffff8d78f71d RDI: ffffffff8bbf81e0
RBP: ffffc9000bd8f7b0 R08: ffffffff8f7deb77 R09: 1ffffffff1efbd6e
R10: dffffc0000000000 R11: fffffbfff1efbd6f R12: ffff8880306f1e80
R13: dffffc0000000000 R14: ffffffff8dc95300 R15: ffff8880b863b498
context_switch kernel/sched/core.c:5260 [inline]
__schedule+0x14c4/0x5030 kernel/sched/core.c:6864
__schedule_loop kernel/sched/core.c:6946 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6961
futex_do_wait kernel/futex/waitwake.c:358 [inline]
__futex_wait+0x1c3/0x3d0 kernel/futex/waitwake.c:687
futex_wait+0x104/0x360 kernel/futex/waitwake.c:715
do_futex+0x333/0x420 kernel/futex/syscalls.c:130
__do_sys_futex kernel/futex/syscalls.c:207 [inline]
__se_sys_futex+0x36f/0x400 kernel/futex/syscalls.c:188
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: 0033:0x7f88c078f749
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:00007f88c155d0e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: ffffffffffffffda RBX: 00007f88c09e5fa8 RCX: 00007f88c078f749
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f88c09e5fa8
RBP: 00007f88c09e5fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f88c09e6038 R14: 00007ffe012213b0 R15: 00007ffe01221498
rcu: rcu_preempt kthread starved for 10506 jiffies! g125141 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:26768 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5257 [inline]
__schedule+0x14bc/0x5030 kernel/sched/core.c:6864
__schedule_loop kernel/sched/core.c:6946 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6961
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+0x599/0xb30 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
rcu: Stack dump where RCU GP kthread last ran:
CPU: 1 UID: 0 PID: 194 Comm: kworker/u8:6 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Workqueue: events_unbound toggle_allocation_gate
RIP: 0010:csd_lock_wait kernel/smp.c:342 [inline]
RIP: 0010:smp_call_function_many_cond+0xccf/0x12d0 kernel/smp.c:877
Code: 45 8b 2c 24 44 89 ee 83 e6 01 31 ff e8 8a 98 0b 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 35 94 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 19 94
RSP: 0018:ffffc90003067660 EFLAGS: 00000293
RAX: ffffffff81b64557 RBX: 1ffff110170c856d RCX: ffff88801e723d00
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc900030677e0 R08: ffffffff8f7deb77 R09: 1ffffffff1efbd6e
R10: dffffc0000000000 R11: fffffbfff1efbd6f R12: ffff8880b8642b68
R13: dffffc0000000000 R14: ffff8880b873bb00 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff888125fba000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2f01eff8 CR3: 000000000dd38000 CR4: 00000000003526f0
Call Trace:
on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1043
on_each_cpu include/linux/smp.h:71 [inline]
smp_text_poke_sync_each_cpu arch/x86/kernel/alternative.c:2711 [inline]
smp_text_poke_batch_finish+0x5f9/0x1130 arch/x86/kernel/alternative.c:2921
arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146
static_key_enable_cpuslocked+0x128/0x250 kernel/jump_label.c:210
static_key_enable+0x1a/0x20 kernel/jump_label.c:223
toggle_allocation_gate+0xad/0x240 mm/kfence/core.c:854
process_one_work+0x93a/0x15e0 kernel/workqueue.c:3261
process_scheduled_works kernel/workqueue.c:3344 [inline]
worker_thread+0x9b0/0xee0 kernel/workqueue.c:3425
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x599/0xb30 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246