rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 1-...!: (1 GPs behind) idle=cc14/1/0x4000000000000000 softirq=30636/30637 fqs=0
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P7927/1:b..l
rcu: (detected by 0, t=10502 jiffies, g=38397, q=436 ncpus=2)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 7979 Comm: syz.2.435 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/10/2026
RIP: 0010:lookup_object lib/debugobjects.c:438 [inline]
RIP: 0010:debug_object_deactivate+0x9e/0x250 lib/debugobjects.c:938
Code: c8 48 c1 e9 2f 83 e1 f8 4c 8d 3c c9 49 81 c7 c0 4a 96 9a 48 8d 1c c9 48 81 c3 c8 4a 96 9a 48 89 df e8 66 a0 f3 06 48 89 04 24 <4c> 89 f8 48 c1 e8 03 80 3c 28 00 74 08 4c 89 ff e8 9d f3 55 fd 4d
RSP: 0018:ffffc90000a08d68 EFLAGS: 00000046
RAX: 0000000000000082 RBX: ffffffff9a9bf3c8 RCX: 0000000000000001
RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffffc90000a08cc0
RBP: dffffc0000000000 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff52000141198 R12: ffff88802269a300
R13: dffffc0000000000 R14: ffff8880b8728360 R15: ffffffff9a9bf3c0
FS: 0000555591676500(0000) GS:ffff888125058000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055556414e9f8 CR3: 0000000031f4f000 CR4: 0000000000350ef0
Call Trace:
debug_hrtimer_deactivate kernel/time/hrtimer.c:490 [inline]
__run_hrtimer kernel/time/hrtimer.c:2000 [inline]
__hrtimer_run_queues+0x239/0xa10 kernel/time/hrtimer.c:2096
hrtimer_interrupt+0x448/0x910 kernel/time/hrtimer.c:2215
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1051 [inline]
__sysvec_apic_timer_interrupt+0x102/0x430 arch/x86/kernel/apic/apic.c:1068
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline]
sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1062
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:rcu_is_watching_curr_cpu include/linux/context_tracking.h:128 [inline]
RIP: 0010:rcu_is_watching+0x5a/0xb0 kernel/rcu/tree.c:752
Code: f0 48 c1 e8 03 42 80 3c 38 00 74 08 4c 89 f7 e8 9c b0 88 00 48 c7 c3 d8 b8 6d 93 49 03 1e 48 89 d8 48 c1 e8 03 42 0f b6 04 38 <84> c0 75 34 8b 03 65 ff 0d b9 31 c1 11 74 11 83 e0 04 c1 e8 02 5b
RSP: 0018:ffffc90002f7f7e0 EFLAGS: 00000216
RAX: 0000000000000000 RBX: ffff8880b87338d8 RCX: 0000000080000002
RDX: 0000000000000000 RSI: ffffffff8c4bd360 RDI: ffffffff8c4bd320
RBP: ffffc90002f7f9f8 R08: ffffffff905776f7 R09: 1ffffffff20aeede
R10: dffffc0000000000 R11: fffffbfff20aeedf R12: ffff88804b92be2c
R13: dffffc0000000000 R14: ffffffff8e4f87d8 R15: dffffc0000000000
trace_sched_entry_tp include/trace/events/sched.h:882 [inline]
__schedule+0xe3/0x56c0 kernel/sched/core.c:7077
__schedule_loop kernel/sched/core.c:7311 [inline]
schedule+0x164/0x2b0 kernel/sched/core.c:7326
futex_do_wait kernel/futex/waitwake.c:387 [inline]
__futex_wait+0x1d3/0x400 kernel/futex/waitwake.c:722
futex_wait+0x121/0x390 kernel/futex/waitwake.c:750
do_futex+0x3e7/0x4e0 kernel/futex/syscalls.c:133
__do_sys_futex kernel/futex/syscalls.c:210 [inline]
__se_sys_futex+0x3a8/0x450 kernel/futex/syscalls.c:191
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f3a0039de59
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fff4c91fd68 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: ffffffffffffffda RBX: 0000000000043978 RCX: 00007f3a0039de59
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f3a0062609c
RBP: 0000000000000032 R08: 3fffffffffffffff R09: 0000000000000000
R10: 00007fff4c91fe70 R11: 0000000000000246 R12: 00007fff4c91fe90
R13: 00007f3a0062609c R14: 00000000000439aa R15: 00007fff4c91fe70
task:syz.3.422 state:R running task stack:26072 pid:7927 tgid:7904 ppid:5617 task_flags:0x40044c flags:0x00080001
Call Trace:
context_switch kernel/sched/core.c:5510 [inline]
__schedule+0x17d9/0x56c0 kernel/sched/core.c:7234
preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7556
irqentry_exit_to_kernel_mode include/linux/irq-entry-common.h:539 [inline]
irqentry_exit+0x14f/0x8f0 kernel/entry/common.c:167
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674
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+0x97/0x2c0 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 3d 01 00 00 4c 89 cb 48 f7 d3 4c 01 fb 41 80 3b 00 <0f> 85 9e 01 00 00 49 ff c3 48 ff c3 75 ee e9 1d 01 00 00 44 89 dd
RSP: 0018:ffffc9000315ed68 EFLAGS: 00000246
RAX: ffffc9000315f301 RBX: ffffffffffffffff RCX: ffffffff8176fef4
RDX: 0000000000000001 RSI: 0000000000000010 RDI: ffffc9000315eeb8
RBP: 0000000000000000 R08: ffffc9000315eec7 R09: 1ffff9200062bdd8
R10: dffffc0000000000 R11: fffff5200062bdd8 R12: 0000000000000002
R13: ffffffff90f9beca R14: fffff5200062bdd9 R15: 1ffff9200062bdd7
__asan_memset+0x22/0x50 mm/kasan/shadow.c:84
unwind_next_frame+0xd04/0x2550 arch/x86/kernel/unwind_orc.c:621
arch_stack_walk+0x11b/0x150 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122
save_stack+0x122/0x230 mm/page_owner.c:165
__reset_page_owner+0x71/0x1f0 mm/page_owner.c:320
reset_page_owner include/linux/page_owner.h:25 [inline]
__free_pages_prepare mm/page_alloc.c:1406 [inline]
free_unref_folios+0xd84/0x14a0 mm/page_alloc.c:3011
folios_put_refs+0x9e9/0xb30 mm/swap.c:1057
folio_batch_release include/linux/folio_batch.h:101 [inline]
shmem_undo_range+0x4e6/0x15d0 mm/shmem.c:1149
shmem_truncate_range mm/shmem.c:1277 [inline]
shmem_evict_inode+0x280/0xa80 mm/shmem.c:1407
evict+0x624/0xb50 fs/inode.c:825
dentry_kill+0x1b9/0x880 fs/dcache.c:826
finish_dput+0x1a/0x260 fs/dcache.c:1001
__fput+0x675/0xa50 fs/file_table.c:520
task_work_run+0x1d9/0x270 kernel/task_work.c:233
exit_task_work include/linux/task_work.h:40 [inline]
do_exit+0x73a/0x2360 kernel/exit.c:1004
do_group_exit+0x22d/0x2f0 kernel/exit.c:1147
get_signal+0x121b/0x12c0 kernel/signal.c:3038
arch_do_signal_or_restart+0xbb/0x860 arch/x86/kernel/signal.c:337
__exit_to_user_mode_loop kernel/entry/common.c:66 [inline]
exit_to_user_mode_loop+0x104/0x730 kernel/entry/common.c:101
__exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline]
syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:230 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:318 [inline]
do_syscall_64+0x353/0x580 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fc04859de59
RSP: 002b:00007fc04949d028 EFLAGS: 00000246 ORIG_RAX: 000000000000012b
RAX: 0000000000010106 RBX: 00007fc048826090 RCX: 00007fc04859de59
RDX: 0000000000010106 RSI: 00002000000000c0 RDI: 0000000000000006
RBP: 00007fc048633e6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fc048826128 R14: 00007fc048826090 R15: 00007fff54431ef8
rcu: rcu_preempt kthread starved for 10502 jiffies! g38397 f0x0 RCU_GP_WAIT_FQS(5) ->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:27736 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5510 [inline]
__schedule+0x17d9/0x56c0 kernel/sched/core.c:7234
__schedule_loop kernel/sched/core.c:7311 [inline]
schedule+0x164/0x2b0 kernel/sched/core.c:7326
schedule_timeout+0x152/0x2c0 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x30c/0x11f0 kernel/rcu/tree.c:2123
rcu_gp_kthread+0x9e/0x2b0 kernel/rcu/tree.c:2325
kthread+0x388/0x470 kernel/kthread.c:436
ret_from_fork+0x514/0xb70 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: 0 UID: 0 PID: 48 Comm: kworker/u8:3 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/10/2026
Workqueue: events_unbound toggle_allocation_gate
RIP: 0010:csd_lock_wait kernel/smp.c:342 [inline]
RIP: 0010:smp_call_function_many_cond+0x10b0/0x14b0 kernel/smp.c:892
Code: c0 75 73 41 8b 1e 89 de 83 e6 01 31 ff e8 d8 1e 0c 00 83 e3 01 48 bb 00 00 00 00 00 fc ff df 75 07 e8 84 1a 0c 00 eb 37 f3 90 <41> 0f b6 04 1c 84 c0 75 10 41 f7 06 01 00 00 00 74 1e e8 69 1a 0c
RSP: 0018:ffffc90000b87720 EFLAGS: 00000293
RAX: ffffffff81ba57d7 RBX: dffffc0000000000 RCX: ffff88801b7edd00
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc90000b87860 R08: ffffffff905776f7 R09: 1ffffffff20aeede
R10: dffffc0000000000 R11: fffffbfff20aeedf R12: 1ffff110170e81d1
R13: ffff8880b863c448 R14: ffff8880b8740e88 R15: 0000000000000001
FS: 0000000000000000(0000) GS:ffff888124f58000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c436dc1 CR3: 000000000e946000 CR4: 0000000000350ef0
Call Trace:
on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1057
on_each_cpu include/linux/smp.h:72 [inline]
smp_text_poke_sync_each_cpu arch/x86/kernel/alternative.c:2773 [inline]
smp_text_poke_batch_finish+0x5fd/0x1110 arch/x86/kernel/alternative.c:2983
arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146
static_key_enable_cpuslocked+0x128/0x240 kernel/jump_label.c:210
static_key_enable+0x1a/0x20 kernel/jump_label.c:223
toggle_allocation_gate+0xab/0x290 mm/kfence/core.c:911
process_one_work kernel/workqueue.c:3322 [inline]
process_scheduled_works+0xa8e/0x14e0 kernel/workqueue.c:3405
worker_thread+0xa47/0xfb0 kernel/workqueue.c:3486
kthread+0x388/0x470 kernel/kthread.c:436
ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245