rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P5194/1:b..l
rcu: (detected by 1, t=10502 jiffies, g=70857, q=167 ncpus=2)
task:udevd state:R running task stack:22760 pid:5194 tgid:5194 ppid:1 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:native_save_fl arch/x86/include/asm/irqflags.h:32 [inline]
RIP: 0010:arch_local_save_flags arch/x86/include/asm/irqflags.h:109 [inline]
RIP: 0010:arch_local_irq_save arch/x86/include/asm/irqflags.h:127 [inline]
RIP: 0010:lock_release+0xaa/0x3e0 kernel/locking/lockdep.c:5885
Code: 92 41 83 bf 2c 0b 00 00 00 0f 85 1e 02 00 00 49 81 3e 40 03 32 93 0f 84 11 02 00 00 48 c7 44 24 20 00 00 00 00 9c 8f 44 24 20 <48> 8b 5c 24 20 fa 48 c7 c7 79 27 72 8d e8 24 39 a9 09 65 ff 05 2d
RSP: 0018:ffffc90003a1f810 EFLAGS: 00000202
RAX: 0000000000000000 RBX: ffffffff90197101 RCX: 5f5b1b51a0ab1100
RDX: ffffc90003a1f901 RSI: ffffffff8bbf08c0 RDI: ffffffff8bbf0880
RBP: dffffc0000000000 R08: ffffc90003a1fe80 R09: ffffc90003a1f998
R10: dffffc0000000000 R11: fffff52000743f35 R12: ffffc90003a1fe90
R13: ffffffff81738c45 R14: ffffffff8df3d6e0 R15: ffff88807c540000
rcu_lock_release include/linux/rcupdate.h:341 [inline]
rcu_read_unlock include/linux/rcupdate.h:897 [inline]
class_rcu_destructor include/linux/rcupdate.h:1195 [inline]
unwind_next_frame+0x19a9/0x2390 arch/x86/kernel/unwind_orc.c:680
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
getname_flags+0xb8/0x540 fs/namei.c:146
getname include/linux/fs.h:2924 [inline]
do_sys_openat2+0xbc/0x1c0 fs/open.c:1431
do_sys_open fs/open.c:1452 [inline]
__do_sys_openat fs/open.c:1468 [inline]
__se_sys_openat fs/open.c:1463 [inline]
__x64_sys_openat+0x138/0x170 fs/open.c:1463
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: 0033:0x7f1ee06a7407
RSP: 002b:00007fff9bafd2d0 EFLAGS: 00000202 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f1ee0ded880 RCX: 00007f1ee06a7407
RDX: 0000000000080000 RSI: 00007fff9bafd450 RDI: ffffffffffffff9c
RBP: 0000000000000008 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 000055ed92d587f5
R13: 000055ed92d587f5 R14: 0000000000000001 R15: 00007fff9bb01aa0
rcu: rcu_preempt kthread timer wakeup didn't happen for 10521 jiffies! g70857 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: Possible timer handling issue on cpu=0 timer-softirq=78115
rcu: rcu_preempt kthread starved for 10522 jiffies! g70857 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->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:I stack:27328 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 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 16899 Comm: syz.3.2812 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:pv_wait_head_or_lock kernel/locking/qspinlock_paravirt.h:430 [inline]
RIP: 0010:__pv_queued_spin_lock_slowpath+0x6d1/0xb60 kernel/locking/qspinlock.c:325
Code: c7 84 24 90 00 00 00 00 01 48 b8 00 00 00 00 00 fc ff df 48 8b 4c 24 20 0f b6 04 01 84 c0 75 46 80 3b 00 74 09 f3 90 41 ff c6 <75> d3 eb 4b 48 89 df be 02 00 00 00 e8 6e 8f dc f6 48 8d bc 24 90
RSP: 0018:ffffc9000d207660 EFLAGS: 00000286
RAX: 0000000000000000 RBX: ffff888031464308 RCX: 1ffff1100628c861
RDX: ffffc9000e501000 RSI: 00000000000087e3 RDI: ffff8880b883af94
RBP: ffffc9000d207778 R08: ffffffff8f7cee77 R09: 1ffffffff1ef9dce
R10: dffffc0000000000 R11: fffffbfff1ef9dcf R12: 1ffffffff1bb51bc
R13: 0000000000000000 R14: 00000000ffffe606 R15: 1ffff1100628c861
FS: 00007fe0575f46c0(0000) GS:ffff88812613b000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fe0575f3f98 CR3: 000000003e748000 CR4: 0000000000350ef0
Call Trace:
pv_queued_spin_lock_slowpath arch/x86/include/asm/paravirt.h:557 [inline]
queued_spin_lock_slowpath+0x43/0x50 arch/x86/include/asm/qspinlock.h:51
queued_spin_lock include/asm-generic/qspinlock.h:114 [inline]
do_raw_spin_lock+0x21f/0x290 kernel/locking/spinlock_debug.c:116
spin_lock_bh include/linux/spinlock.h:356 [inline]
lock_sock_nested+0x6a/0x100 net/core/sock.c:3723
lock_sock include/net/sock.h:1679 [inline]
tipc_sendstream+0x47/0x70 net/tipc/socket.c:1545
sock_sendmsg_nosec net/socket.c:727 [inline]
__sock_sendmsg+0x21c/0x270 net/socket.c:742
____sys_sendmsg+0x52d/0x830 net/socket.c:2630
___sys_sendmsg+0x21f/0x2a0 net/socket.c:2684
__sys_sendmmsg+0x227/0x430 net/socket.c:2773
__do_sys_sendmmsg net/socket.c:2800 [inline]
__se_sys_sendmmsg net/socket.c:2797 [inline]
__x64_sys_sendmmsg+0xa0/0xc0 net/socket.c:2797
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: 0033:0x7fe05678f749
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:00007fe0575f4038 EFLAGS: 00000246 ORIG_RAX: 0000000000000133
RAX: ffffffffffffffda RBX: 00007fe0569e6090 RCX: 00007fe05678f749
RDX: 0400000000000121 RSI: 0000200000000640 RDI: 0000000000000004
RBP: 00007fe056813f91 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000200000d1 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fe0569e6128 R14: 00007fe0569e6090 R15: 00007ffefbd46018