rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P10643/1:b..l P5898/1:b..l
rcu: (detected by 1, t=10503 jiffies, g=45577, q=391 ncpus=2)
task:udevd state:R running task stack:22712 pid:5898 tgid:5898 ppid:5200 task_flags:0x400140 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5258 [inline]
__schedule+0x150e/0x5070 kernel/sched/core.c:6866
preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7193
irqentry_exit+0x5d8/0x660 kernel/entry/common.c:216
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:handle_mounts fs/namei.c:1673 [inline]
RIP: 0010:step_into_slowpath+0xc9/0x7d0 fs/namei.c:2043
Code: 89 44 24 60 4c 89 74 24 68 4c 8d 6b 38 4c 89 e8 48 c1 e8 03 48 89 44 24 30 42 0f b6 04 20 84 c0 0f 85 d0 04 00 00 45 8b 7d 00 <44> 89 fe 81 e6 00 01 00 00 31 ff e8 37 1d 83 ff 41 81 e7 00 01 00
RSP: 0018:ffffc9000441f8a0 EFLAGS: 00000246
RAX: 0000000000000000 RBX: ffffc9000441fb80 RCX: ffff88802efe0000
RDX: 0000000000000000 RSI: 0000000000000002 RDI: ffffc9000441fb80
RBP: ffffc9000441f970 R08: ffff8880235a1ae0 R09: 1ffff110046b435c
R10: dffffc0000000000 R11: ffffed10046b435d R12: dffffc0000000000
R13: ffffc9000441fbb8 R14: ffff8880235a1a70 R15: 0000000000000500
step_into fs/namei.c:2091 [inline]
walk_component fs/namei.c:2227 [inline]
link_path_walk+0xd50/0x18d0 fs/namei.c:2589
path_lookupat+0xe4/0x8c0 fs/namei.c:2745
filename_lookup+0x212/0x570 fs/namei.c:2775
user_path_at+0x3a/0x60 fs/namei.c:3567
do_utimes_path fs/utimes.c:96 [inline]
do_utimes+0x131/0x2a0 fs/utimes.c:141
__do_sys_utimensat fs/utimes.c:160 [inline]
__se_sys_utimensat fs/utimes.c:144 [inline]
__x64_sys_utimensat+0x14f/0x230 fs/utimes.c:144
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f8bdcb15a1a
RSP: 002b:00007ffd5f725848 EFLAGS: 00000246 ORIG_RAX: 0000000000000118
RAX: ffffffffffffffda RBX: 00007ffd5f726220 RCX: 00007f8bdcb15a1a
RDX: 0000000000000000 RSI: 00007ffd5f726220 RDI: 00000000ffffff9c
RBP: 00007ffd5f72622f R08: 0000000000000075 R09: 0000000000000000
R10: 0000000000000100 R11: 0000000000000246 R12: 00007ffd5f725d00
R13: 00007ffd5f725900 R14: 0000560dcd3986d7 R15: 0000560dd3a61030
task:dhcpcd-run-hook state:R running task stack:24312 pid:10643 tgid:10643 ppid:5495 task_flags:0x40040c flags:0x00080003
Call Trace:
context_switch kernel/sched/core.c:5258 [inline]
__schedule+0x150e/0x5070 kernel/sched/core.c:6866
preempt_schedule_notrace+0xd1/0x110 kernel/sched/core.c:7143
preempt_schedule_notrace_thunk+0x16/0x30 arch/x86/entry/thunk.S:13
rcu_is_watching+0x7f/0xb0 kernel/rcu/tree.c:752
rcu_read_lock include/linux/rcupdate.h:868 [inline]
class_rcu_constructor include/linux/rcupdate.h:1195 [inline]
unwind_next_frame+0xd4/0x23d0 arch/x86/kernel/unwind_orc.c:495
arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
kasan_save_stack+0x3e/0x60 mm/kasan/common.c:57
kasan_record_aux_stack+0xbd/0xd0 mm/kasan/generic.c:556
__call_rcu_common kernel/rcu/tree.c:3119 [inline]
call_rcu+0x157/0x9c0 kernel/rcu/tree.c:3239
slab_free_hook mm/slub.c:2504 [inline]
slab_free mm/slub.c:6674 [inline]
kmem_cache_free+0x488/0x620 mm/slub.c:6785
exit_mmap+0x52c/0xb10 mm/mmap.c:1302
__mmput+0x118/0x430 kernel/fork.c:1177
exit_mm+0x1da/0x2c0 kernel/exit.c:581
do_exit+0x850/0x25b0 kernel/exit.c:959
do_group_exit+0x21c/0x2d0 kernel/exit.c:1112
get_signal+0x1285/0x1340 kernel/signal.c:3034
arch_do_signal_or_restart+0x9a/0x7a0 arch/x86/kernel/signal.c:337
__exit_to_user_mode_loop kernel/entry/common.c:41 [inline]
exit_to_user_mode_loop+0x87/0x4f0 kernel/entry/common.c:75
__exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline]
syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline]
syscall_exit_to_user_mode_work include/linux/entry-common.h:159 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:194 [inline]
do_syscall_64+0x2d0/0xf80 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f8ef964d287
RSP: 002b:00007fff188e0f78 EFLAGS: 00000202 ORIG_RAX: 000000000000003d
RAX: 0000000000000000 RBX: 00007f8ef9361c80 RCX: 00007f8ef94b1407
RDX: 00007fff188e0f80 RSI: 00007fff188e10b0 RDI: 0000000000000011
RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 000055660732dc60
R13: 0000000000000001 R14: 000055660732c910 R15: 00007f8ef96cb460
rcu: rcu_preempt kthread starved for 10578 jiffies! g45577 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->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:I stack:25664 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5258 [inline]
__schedule+0x150e/0x5070 kernel/sched/core.c:6866
preempt_schedule_common+0x83/0xd0 kernel/sched/core.c:7050
preempt_schedule+0xae/0xc0 kernel/sched/core.c:7074
preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12
__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline]
_raw_spin_unlock_irqrestore+0xfd/0x110 kernel/locking/spinlock.c:194
prepare_to_swait_event+0x341/0x380 kernel/sched/swait.c:120
rcu_gp_fqs_loop+0x2cc/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: 0 Comm: swapper/1 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:pv_native_safe_halt+0x13/0x20 arch/x86/kernel/paravirt.c:82
Code: cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d 33 9e 2a 00 f3 0f 1e fa fb f4 48 ee 02 00 cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90
RSP: 0000:ffffc90000197de0 EFLAGS: 000002c6
RAX: 916c82ee3aeeda00 RBX: ffffffff819786ba RCX: 916c82ee3aeeda00
RDX: 0000000000000001 RSI: ffffffff8d997e54 RDI: ffffffff8be07960
RBP: ffffc90000197f10 R08: ffff8880b87336db R09: 1ffff110170e66db
R10: dffffc0000000000 R11: ffffed10170e66dc R12: ffffffff8fa22f70
R13: 1ffff11003ad4b70 R14: 0000000000000001 R15: 0000000000000001
FS: 0000000000000000(0000) GS:ffff888125d25000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fff188e0f80 CR3: 0000000032e40000 CR4: 00000000003526f0
Call Trace:
arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline]
default_idle+0x13/0x20 arch/x86/kernel/process.c:767
default_idle_call+0x73/0xb0 kernel/sched/idle.c:122
cpuidle_idle_call kernel/sched/idle.c:191 [inline]
do_idle+0x1ea/0x520 kernel/sched/idle.c:332
cpu_startup_entry+0x44/0x60 kernel/sched/idle.c:430
start_secondary+0x101/0x110 arch/x86/kernel/smpboot.c:312
common_startup_64+0x13e/0x147