rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P7788/1:b..l P5825/1:b..l
rcu: (detected by 0, t=10503 jiffies, g=19029, q=682 ncpus=2)
task:udevd state:R running task stack:25736 pid:5825 tgid:5825 ppid:5196 task_flags:0x400140 flags:0x00080001
Call Trace:
context_switch kernel/sched/core.c:5325 [inline]
__schedule+0x1798/0x4cc0 kernel/sched/core.c:6929
preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7256
irqentry_exit+0x6f/0x90 kernel/entry/common.c:211
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:on_stack arch/x86/include/asm/stacktrace.h:58 [inline]
RIP: 0010:stack_access_ok arch/x86/kernel/unwind_orc.c:393 [inline]
RIP: 0010:deref_stack_reg+0xa5/0x230 arch/x86/kernel/unwind_orc.c:403
Code: 00 00 00 fc ff df 4c 89 74 24 08 4d 8b 77 10 4c 89 fd 48 c1 ed 03 0f b6 44 35 00 84 c0 0f 85 3c 01 00 00 41 83 3f 00 0f 95 c0 <4c> 39 c3 0f 96 c1 20 c1 4d 39 c6 0f 97 c0 20 c8 3c 01 75 18 49 8d
RSP: 0018:ffffc90003fcf340 EFLAGS: 00000202
RAX: 0000000000000001 RBX: ffffc90003fc8000 RCX: 0000000000000000
RDX: ffffc90003fcf508 RSI: dffffc0000000000 RDI: ffffc90003fcf4c8
RBP: 1ffff920007f9e99 R08: ffffc90003fcf4b8 R09: 0000000000000000
R10: ffffc90003fcf518 R11: fffff520007f9ea5 R12: 1ffff920007f9e9a
R13: 1ffff920007f9e9b R14: ffffc90003fd0000 R15: ffffc90003fcf4c8
unwind_next_frame+0x17c4/0x2390 arch/x86/kernel/unwind_orc.c:-1
__unwind_start+0x5b9/0x760 arch/x86/kernel/unwind_orc.c:758
unwind_start arch/x86/include/asm/unwind.h:64 [inline]
arch_stack_walk+0xe4/0x150 arch/x86/kernel/stacktrace.c:24
stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
kasan_save_stack mm/kasan/common.c:56 [inline]
kasan_save_track+0x3e/0x80 mm/kasan/common.c:77
__kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:587
kasan_save_free_info mm/kasan/kasan.h:406 [inline]
poison_slab_object mm/kasan/common.c:252 [inline]
__kasan_slab_free+0x5c/0x80 mm/kasan/common.c:284
kasan_slab_free include/linux/kasan.h:234 [inline]
slab_free_hook mm/slub.c:2543 [inline]
slab_free mm/slub.c:6642 [inline]
kfree+0x19a/0x6d0 mm/slub.c:6849
tomoyo_realpath_from_path+0x598/0x5d0 security/tomoyo/realpath.c:286
tomoyo_get_realpath security/tomoyo/file.c:151 [inline]
tomoyo_path2_perm+0x265/0x680 security/tomoyo/file.c:922
tomoyo_path_rename+0x141/0x190 security/tomoyo/tomoyo.c:300
security_path_rename+0x250/0x490 security/security.c:2065
do_renameat2+0x52b/0xa50 fs/namei.c:5352
__do_sys_rename fs/namei.c:5411 [inline]
__se_sys_rename fs/namei.c:5409 [inline]
__x64_sys_rename+0x82/0x90 fs/namei.c:5409
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: 0033:0x7f28df67acc7
RSP: 002b:00007ffca0d8c398 EFLAGS: 00000206 ORIG_RAX: 0000000000000052
RAX: ffffffffffffffda RBX: 000055dacf70b8a0 RCX: 00007f28df67acc7
RDX: 000055dacf6e4010 RSI: 00007ffca0d8c3b0 RDI: 00007ffca0d8c7b0
RBP: 000055dacf7ba720 R08: 00000000000001e0 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 00007ffca0d8c3b0
R13: 00007ffca0d8c7b0 R14: 0000000000000000 R15: 000055dac0a4f9dd
task:syz.0.455 state:R running task stack:26216 pid:7788 tgid:7787 ppid:5833 task_flags:0x40054c flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5325 [inline]
__schedule+0x1798/0x4cc0 kernel/sched/core.c:6929
preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7256
irqentry_exit+0x6f/0x90 kernel/entry/common.c:211
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:kasan_mem_to_shadow include/linux/kasan.h:65 [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+0x61/0x2c0 mm/kasan/generic.c:200
Code: 1e fa 49 b9 00 00 00 00 00 00 00 ff f3 0f 1e fa 4c 39 cf 0f 82 58 02 00 00 49 89 ff 49 c1 ef 03 49 ba 00 00 00 00 00 fc ff df <4f> 8d 1c 17 49 ff c8 4d 89 c1 49 c1 e9 03 48 bb 01 00 00 00 00 fc
RSP: 0018:ffffc9000c1c6dc0 EFLAGS: 00000a06
RAX: 1ffff92001838d01 RBX: 0000000000000010 RCX: ffffffff81739838
RDX: 0000000000000001 RSI: 0000000000000010 RDI: ffffc9000c1c6f38
RBP: 0000000000000000 R08: ffffc9000c1c6f48 R09: ffff800000000000
R10: dffffc0000000000 R11: ffffffff81ac2e10 R12: ffffc9000c1c7268
R13: ffffc9000c1c6f38 R14: ffffc9000c1c6f38 R15: 1ffff92001838de7
__asan_memset+0x22/0x50 mm/kasan/shadow.c:84
unwind_next_frame+0xc98/0x2390 arch/x86/kernel/unwind_orc.c:592
arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
kasan_save_stack mm/kasan/common.c:56 [inline]
kasan_save_track+0x3e/0x80 mm/kasan/common.c:77
unpoison_slab_object mm/kasan/common.c:342 [inline]
__kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:368
kasan_slab_alloc include/linux/kasan.h:252 [inline]
slab_post_alloc_hook mm/slub.c:4978 [inline]
slab_alloc_node mm/slub.c:5288 [inline]
kmem_cache_alloc_noprof+0x367/0x6e0 mm/slub.c:5295
kmem_alloc_batch lib/debugobjects.c:371 [inline]
fill_pool+0x100/0x570 lib/debugobjects.c:403
debug_objects_fill_pool lib/debugobjects.c:725 [inline]
debug_object_activate+0x383/0x420 lib/debugobjects.c:814
debug_rcu_head_queue kernel/rcu/rcu.h:236 [inline]
__call_rcu_common kernel/rcu/tree.c:3108 [inline]
call_rcu+0xaa/0x9c0 kernel/rcu/tree.c:3243
slab_free_hook mm/slub.c:2507 [inline]
slab_free mm/slub.c:6642 [inline]
kmem_cache_free+0x4b5/0x690 mm/slub.c:6752
anon_vma_free mm/rmap.c:136 [inline]
__put_anon_vma+0x12b/0x2d0 mm/rmap.c:2777
put_anon_vma include/linux/rmap.h:117 [inline]
unlink_anon_vmas+0x503/0x670 mm/rmap.c:443
free_pgtables+0x57a/0x9c0 mm/memory.c:399
exit_mmap+0x43c/0xb40 mm/mmap.c:1291
__mmput+0x118/0x430 kernel/fork.c:1133
exit_mm+0x1da/0x2c0 kernel/exit.c:582
do_exit+0x648/0x2300 kernel/exit.c:954
do_group_exit+0x21c/0x2d0 kernel/exit.c:1107
get_signal+0x1285/0x1340 kernel/signal.c:3034
arch_do_signal_or_restart+0xa0/0x790 arch/x86/kernel/signal.c:337
exit_to_user_mode_loop+0x72/0x130 kernel/entry/common.c:40
exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline]
syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline]
do_syscall_64+0x2bd/0xfa0 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f1a43b8f749
RSP: 002b:00007f1a449680e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 00007f1a43de5fa8 RCX: 00007f1a43b8f749
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f1a43de5fa8
RBP: 00007f1a43de5fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f1a43de6038 R14: 00007ffcb0564b80 R15: 00007ffcb0564c68
rcu: rcu_preempt kthread starved for 10503 jiffies! g19029 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:27224 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5325 [inline]
__schedule+0x1798/0x4cc0 kernel/sched/core.c:6929
__schedule_loop kernel/sched/core.c:7011 [inline]
schedule+0x165/0x360 kernel/sched/core.c:7026
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:
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 116 Comm: kworker/1:2 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Workqueue: events_power_efficient gc_worker
RIP: 0010:__lock_acquire+0x45/0xd20 kernel/locking/lockdep.c:5098
Code: 31 ff 83 3d 1c f9 df 0d 00 0f 84 7e 0c 00 00 48 8b 03 48 3d 40 a3 32 93 0f 84 6f 0c 00 00 41 89 cc 41 89 d6 8b 0d 4b 89 43 0c <85> c9 44 0f 44 c1 31 c9 48 3d 30 a3 32 93 41 0f 45 c8 89 4c 24 0c
RSP: 0018:ffffc90000a08b30 EFLAGS: 00000002
RAX: ffffffff99ccd920 RBX: ffff88802822d2c0 RCX: 0000000000000001
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff88801e791e40
RBP: ffffffff89612d54 R08: 0000000000000001 R09: 0000000000000001
R10: dffffc0000000000 R11: ffffffff89612c90 R12: 0000000000000000
R13: ffff88802822d2c0 R14: 0000000000000000 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff888126231000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005555626f0808 CR3: 00000000766cc000 CR4: 00000000003526f0
Call Trace:
lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5868
__raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline]
_raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154
spin_lock include/linux/spinlock.h:351 [inline]
advance_sched+0xc4/0xc90 net/sched/sch_taprio.c:930
__run_hrtimer kernel/time/hrtimer.c:1777 [inline]
__hrtimer_run_queues+0x52c/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:gc_worker+0xbab/0x1380 net/netfilter/nf_conntrack_core.c:1618
Code: e8 da 59 4c f8 48 bb 00 00 00 00 00 fc ff df 44 8b 74 24 14 48 c7 c7 e0 d6 f3 8d 48 8b 74 24 60 e8 8a b8 29 f8 e8 15 5f 33 f8 <48> c7 c7 80 da 72 8c be 52 06 00 00 31 d2 e8 42 eb 1d f8 2e 2e 2e
RSP: 0018:ffffc90002717900 EFLAGS: 00000287
RAX: 0000000000000000 RBX: dffffc0000000000 RCX: d28fdb83aa984d00
RDX: 0000000000000002 RSI: ffffffff8d8fb724 RDI: ffff88801e791e40
RBP: ffffc90002717a50 R08: ffffffff8f7d1e77 R09: 1ffffffff1efa3ce
R10: dffffc0000000000 R11: fffffbfff1efa3cf R12: 1ffff1100f142cc9
R13: 000000000000a7ad R14: 0000000000030258 R15: 00000000000604b1
process_one_work kernel/workqueue.c:3263 [inline]
process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3346
worker_thread+0x8a0/0xda0 kernel/workqueue.c:3427
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