rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P3638/1:b..l
(detected by 1, t=10503 jiffies, g=59013, q=18 ncpus=2)
task:udevd state:R running task stack:24416 pid:3638 ppid:1 flags:0x00004002
Call Trace:
context_switch kernel/sched/core.c:5245 [inline]
__schedule+0x10ec/0x40b0 kernel/sched/core.c:6562
preempt_schedule_irq+0xb1/0x150 kernel/sched/core.c:6874
irqentry_exit+0x63/0x70 kernel/entry/common.c:439
asm_sysvec_reschedule_ipi+0x16/0x20 arch/x86/include/asm/idtentry.h:696
RIP: 0010:lock_acquire+0x20f/0x490 kernel/locking/lockdep.c:5666
Code: 00 9c 8f 84 24 80 00 00 00 f6 84 24 81 00 00 00 02 0f 85 f5 00 00 00 41 f7 c6 00 02 00 00 74 01 fb 48 c7 44 24 60 0e 36 e0 45 <4b> c7 44 3d 00 00 00 00 00 66 43 c7 44 3d 09 00 00 43 c6 44 3d 0b
RSP: 0018:ffffc900032d77e0 EFLAGS: 00000206
RAX: 0000000000000001 RBX: 0000000000000000 RCX: e41a9a3e825da300
RDX: 0000000000000000 RSI: ffffffff8a6c1780 RDI: ffffffff8abefec0
RBP: ffffc900032d78e8 R08: dffffc0000000000 R09: fffffbfff2119649
R10: fffffbfff2119649 R11: 1ffffffff2119648 R12: 0000000000000001
R13: 1ffff9200065af08 R14: 0000000000000246 R15: dffffc0000000000
rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
rcu_read_lock include/linux/rcupdate.h:791 [inline]
dput+0x53/0x1d0 fs/dcache.c:904
step_into+0x33f/0xf10 fs/namei.c:1859
walk_component fs/namei.c:2012 [inline]
link_path_walk+0x6be/0xe50 fs/namei.c:2333
path_lookupat+0x9d/0x440 fs/namei.c:2486
filename_lookup+0x1f0/0x500 fs/namei.c:2516
user_path_at_empty+0x3e/0x60 fs/namei.c:2913
do_readlinkat+0xd4/0x480 fs/stat.c:468
__do_sys_readlink fs/stat.c:501 [inline]
__se_sys_readlink fs/stat.c:498 [inline]
__x64_sys_readlink+0x7b/0x90 fs/stat.c:498
do_syscall_x64 arch/x86/entry/common.c:46 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fbe4a1153a7
RSP: 002b:00007ffc8b1b8b68 EFLAGS: 00000246 ORIG_RAX: 0000000000000059
RAX: ffffffffffffffda RBX: 00007ffc8b1b9040 RCX: 00007fbe4a1153a7
RDX: 0000000000000400 RSI: 00007ffc8b1b8b70 RDI: 00007ffc8b1b9040
RBP: 00007ffc8b1b8b70 R08: 0000560d8cb41820 R09: 0000000000000020
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000400
R13: 0000560d7e7d0100 R14: 0000000000000000 R15: 00007ffc8b1b9b80
rcu: rcu_preempt kthread starved for 10538 jiffies! g59013 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:27920 pid:16 ppid:2 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5245 [inline]
__schedule+0x10ec/0x40b0 kernel/sched/core.c:6562
schedule+0xb9/0x180 kernel/sched/core.c:6638
schedule_timeout+0x15c/0x280 kernel/time/timer.c:2168
rcu_gp_fqs_loop+0x2f2/0x1310 kernel/rcu/tree.c:1706
rcu_gp_kthread+0x95/0x380 kernel/rcu/tree.c:1905
kthread+0x29d/0x330 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 9617 Comm: syz.6.904 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:arch_static_branch arch/x86/include/asm/jump_label.h:27 [inline]
RIP: 0010:static_key_false include/linux/jump_label.h:207 [inline]
RIP: 0010:native_write_msr arch/x86/include/asm/msr.h:147 [inline]
RIP: 0010:wrmsr arch/x86/include/asm/msr.h:254 [inline]
RIP: 0010:native_apic_msr_write+0x35/0x50 arch/x86/include/asm/apic.h:206
Code: 74 2a 83 ff 30 74 25 eb 10 81 ff d0 00 00 00 74 1b 81 ff e0 00 00 00 74 13 c1 ef 04 81 c7 00 08 00 00 89 f9 89 f0 31 d2 0f 30 <66> 90 c3 89 f6 31 d2 e9 0f 2a f8 02 66 2e 0f 1f 84 00 00 00 00 00
RSP: 0018:ffffc90000007e38 EFLAGS: 00000046
RAX: 000000000001728f RBX: 000000000001728f RCX: 0000000000000838
RDX: 0000000000000000 RSI: 000000000001728f RDI: 0000000000000838
RBP: 0000000000000000 R08: dffffc0000000000 R09: fffffbfff1bfe48e
R10: fffffbfff1bfe48e R11: 1ffffffff1bfe48d R12: dffffc0000000000
R13: 0000000010005df3 R14: ffffffff8c3dab40 R15: dffffc0000000000
FS: 00007f09716b16c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c2c272e CR3: 0000000066a64000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
apic_write arch/x86/include/asm/apic.h:394 [inline]
lapic_next_event+0x5b/0x70 arch/x86/kernel/apic/apic.c:478
clockevents_program_event+0x1bc/0x310 kernel/time/clockevents.c:334
hrtimer_interrupt+0x59d/0x9c0 kernel/time/hrtimer.c:1886
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1107 [inline]
__sysvec_apic_timer_interrupt+0x153/0x5a0 arch/x86/kernel/apic/apic.c:1124
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1118 [inline]
sysvec_apic_timer_interrupt+0x9b/0xc0 arch/x86/kernel/apic/apic.c:1118
asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691
RIP: 0010:lock_is_held_type+0x13a/0x190 kernel/locking/lockdep.c:5710
Code: 75 40 48 c7 04 24 00 00 00 00 9c 8f 04 24 f7 04 24 00 02 00 00 75 46 41 f7 c5 00 02 00 00 74 01 fb 65 48 8b 04 25 28 00 00 00 <48> 3b 44 24 08 75 3c 89 e8 48 83 c4 10 5b 41 5c 41 5d 41 5e 41 5f
RSP: 0018:ffffc9000466fb38 EFLAGS: 00000206
RAX: 9d713fe21187e200 RBX: ffff88802a1ed940 RCX: 9d713fe21187e200
RDX: 0000000000000000 RSI: ffffffff8a6c1780 RDI: ffffffff8abefec0
RBP: 0000000000000000 R08: dffffc0000000000 R09: ffffc9000466fd60
R10: 0000000000000000 R11: 0000000000000018 R12: dffffc0000000000
R13: 0000000000000246 R14: ffffffff8c92b2a0 R15: 00000000ffffffff
lock_is_held include/linux/lockdep.h:283 [inline]
__might_resched+0xf2/0x610 kernel/sched/core.c:9931
__might_fault+0x6d/0x120 mm/memory.c:5848
_copy_from_user+0x27/0x170 lib/usercopy.c:14
copy_from_user include/linux/uaccess.h:161 [inline]
restore_sigcontext arch/x86/kernel/signal.c:92 [inline]
__ia32_sys_rt_sigreturn+0x1e6/0x790 arch/x86/kernel/signal.c:675
do_syscall_x64 arch/x86/entry/common.c:46 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f097072b829
Code: 64 c7 00 16 00 00 00 b8 ff ff ff ff c3 0f 1f 40 00 90 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 c7 c0 0f 00 00 00 0f 05 <0f> 1f 80 00 00 00 00 48 81 ec 48 01 00 00 49 89 d0 64 48 8b 04 25
RSP: 002b:00007f09716b0a80 EFLAGS: 00000202 ORIG_RAX: 000000000000000f
RAX: ffffffffffffffda RBX: 00007f09709e5fa0 RCX: 00007f097072b829
RDX: 00007f09716b0a80 RSI: 00007f09716b0bb0 RDI: 0000000000000021
RBP: 00007f0970813f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000000
R13: 00007f09709e6038 R14: 00007f09709e5fa0 R15: 00007ffda211ec28
sched: RT throttling activated