rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P3559/1:b..l
	(detected by 0, t=10503 jiffies, g=20561, q=13)
task:udevd           state:R  running task     stack:23696 pid: 3559 ppid:     1 flags:0x00004002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5049 [inline]
 __schedule+0x11ef/0x43c0 kernel/sched/core.c:6395
 preempt_schedule_irq+0xbb/0x160 kernel/sched/core.c:6799
 irqentry_exit+0x63/0x70 kernel/entry/common.c:432
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:lock_acquire+0x208/0x400 kernel/locking/lockdep.c:5627
Code: f7 84 24 80 00 00 00 00 02 00 00 43 c6 44 3d 04 f8 0f 85 f1 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 43 c7 44 3d 08 00 00 00 00 65 48 8b 04
RSP: 0018:ffffc90002ddf7a0 EFLAGS: 00000206
RAX: 0000000000000001 RBX: 0000000000000000 RCX: 53932f9bf82cc800
RDX: 0000000000000000 RSI: ffffffff8a2b3a20 RDI: ffffffff8a79f980
RBP: ffffc90002ddf8c0 R08: dffffc0000000000 R09: 1ffffffff203a818
R10: dffffc0000000000 R11: fffffbfff203a819 R12: ffffffff8c31eaa0
R13: 1ffff920005bbf00 R14: 0000000000000246 R15: dffffc0000000000
 rcu_lock_acquire+0x2a/0x30 include/linux/rcupdate.h:313
 rcu_read_lock include/linux/rcupdate.h:740 [inline]
 mntput_no_expire+0xbb/0x790 fs/namespace.c:1174
 path_put fs/namei.c:560 [inline]
 terminate_walk+0x1b6/0x540 fs/namei.c:674
 path_lookupat+0x319/0x440 fs/namei.c:2480
 filename_lookup+0x214/0x540 fs/namei.c:2492
 user_path_at_empty+0x40/0x190 fs/namei.c:2891
 user_path_at include/linux/namei.h:57 [inline]
 vfs_statx+0x107/0x500 fs/stat.c:221
 vfs_fstatat fs/stat.c:243 [inline]
 __do_sys_newfstatat fs/stat.c:411 [inline]
 __se_sys_newfstatat fs/stat.c:405 [inline]
 __x64_sys_newfstatat+0x15f/0x200 fs/stat.c:405
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f95bcc0bb0a
RSP: 002b:00007ffd1fbabbf8 EFLAGS: 00000246 ORIG_RAX: 0000000000000106
RAX: ffffffffffffffda RBX: 00007ffd1fbac090 RCX: 00007f95bcc0bb0a
RDX: 00007ffd1fbabc00 RSI: 00007ffd1fbac090 RDI: 00000000ffffff9c
RBP: 0000559f7ca4f910 R08: 0000000000000000 R09: 0000000000000001
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffd1fbabc90
R13: 0000000000000100 R14: 0000559f575fbbe0 R15: 00007ffd1fbac730
 </TASK>
rcu: rcu_preempt kthread starved for 10527 jiffies! g20561 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:28016 pid:   15 ppid:     2 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5049 [inline]
 __schedule+0x11ef/0x43c0 kernel/sched/core.c:6395
 schedule+0x11b/0x1e0 kernel/sched/core.c:6478
 schedule_timeout+0x184/0x2d0 kernel/time/timer.c:2117
 rcu_gp_fqs_loop+0x2be/0x11d0 kernel/rcu/tree.c:1972
 rcu_gp_kthread+0x9b/0x370 kernel/rcu/tree.c:2145
 kthread+0x436/0x520 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 6848 Comm: syz.5.535 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
RIP: 0010:cgroup_task_frozen include/linux/cgroup.h:904 [inline]
RIP: 0010:recalc_sigpending_tsk kernel/signal.c:159 [inline]
RIP: 0010:recalc_sigpending+0x14d/0x230 kernel/signal.c:184
Code: 81 c6 80 05 00 00 4c 89 f0 48 c1 e8 03 42 0f b6 04 20 84 c0 0f 85 a4 00 00 00 41 0f b7 2e 89 ee 83 e6 40 31 ff e8 43 3b 2e 00 <83> e5 40 75 54 49 c7 c6 c0 fd 31 96 48 c7 c7 c0 fd 31 96 be 04 00
RSP: 0018:ffffc90003e0fb40 EFLAGS: 00000097
RAX: ffffffff814ae8ad RBX: ffff888027fc8000 RCX: ffff888027fc8000
RDX: 0000000000000002 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: ffffc90003e0fe2f R09: 1ffff920007c1fc5
R10: dffffc0000000000 R11: fffff520007c1fc6 R12: dffffc0000000000
R13: 0000000000000000 R14: ffff888027fc8580 R15: ffff888022e4f588
FS:  00007fc72488e6c0(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00002000000c1000 CR3: 0000000047db9000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 dequeue_signal+0xc0/0x440 kernel/signal.c:668
 get_signal+0x6fe/0x12c0 kernel/signal.c:2781
 arch_do_signal_or_restart+0xe7/0x12c0 arch/x86/kernel/signal.c:867
 handle_signal_work kernel/entry/common.c:154 [inline]
 exit_to_user_mode_loop+0x9e/0x130 kernel/entry/common.c:178
 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:214
 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline]
 syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:307
 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fc726634817
Code: 83 c8 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
RSP: 002b:00007fc72488e0e8 EFLAGS: 00000246
RAX: 00000000000000ca RBX: 00007fc7268adfa8 RCX: 00007fc726634819
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007fc7268adfa8
RBP: 00007fc7268adfa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fc7268ae038 R14: 00007ffdd49dc060 R15: 00007ffdd49dc148
 </TASK>
hrtimer: interrupt took 558355778 ns