rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P19455/1:b..l
rcu: 	(detected by 0, t=10502 jiffies, g=143669, q=327 ncpus=1)
task:udevd           state:R  running task     stack:24744 pid:19455 ppid:5141   flags:0x00004002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5382 [inline]
 __schedule+0x15ae/0x4660 kernel/sched/core.c:6701
 preempt_schedule_common+0x82/0xc0 kernel/sched/core.c:6868
 preempt_schedule+0xc0/0xd0 kernel/sched/core.c:6892
 preempt_schedule_thunk+0x1a/0x30 arch/x86/entry/thunk_64.S:45
 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline]
 _raw_spin_unlock_irqrestore+0x111/0x120 kernel/locking/spinlock.c:194
 spin_unlock_irqrestore include/linux/spinlock.h:406 [inline]
 __wake_up_common_lock kernel/sched/wait.c:140 [inline]
 __wake_up_sync_key+0x12c/0x1a0 kernel/sched/wait.c:213
 sock_def_readable+0x1e1/0x420 net/core/sock.c:3362
 unix_dgram_sendmsg+0x1093/0x16e0 net/unix/af_unix.c:2143
 sock_sendmsg_nosec net/socket.c:730 [inline]
 __sock_sendmsg net/socket.c:745 [inline]
 sock_write_iter+0x2dc/0x420 net/socket.c:1161
 call_write_iter include/linux/fs.h:2018 [inline]
 new_sync_write fs/read_write.c:491 [inline]
 vfs_write+0x474/0x9a0 fs/read_write.c:584
 ksys_write+0x151/0x260 fs/read_write.c:637
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f1fce4a7407
RSP: 002b:00007ffd16eb8f80 EFLAGS: 00000202 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f1fceb8c880 RCX: 00007f1fce4a7407
RDX: 0000000000000000 RSI: 00007ffd16eb9027 RDI: 000000000000000a
RBP: 000000000000000a R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 00007f1fceb8c6e8
R13: 0000000000000000 R14: 0000000000000000 R15: 0000560f48e317d0
 </TASK>
rcu: rcu_preempt kthread starved for 10500 jiffies! g143669 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:26664 pid:17    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5382 [inline]
 __schedule+0x15ae/0x4660 kernel/sched/core.c:6701
 preempt_schedule_irq+0xbf/0x150 kernel/sched/core.c:7011
 irqentry_exit+0x67/0x70 kernel/entry/common.c:438
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687
RIP: 0010:__timer_delete_sync+0x1ac/0x2e0 kernel/time/timer.c:1564
Code: 00 4d 85 f6 75 16 e8 e3 9a 10 00 eb 15 e8 dc 9a 10 00 e8 e7 e2 18 09 4d 85 f6 74 ea e8 cd 9a 10 00 fb 65 44 8b 35 5c d0 8c 7e <44> 89 f6 81 e6 00 00 0f 00 31 ff e8 64 9e 10 00 41 81 e6 00 00 0f
RSP: 0018:ffffc90000167aa0 EFLAGS: 00000293
RAX: ffffffff8176e7a3 RBX: ffffc90000167ba0 RCX: ffff88801b670000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90000167b70 R08: ffffffff8e8c8daf R09: 1ffffffff1d191b5
R10: dffffc0000000000 R11: fffffbfff1d191b6 R12: ffffffff8176e70e
R13: 1ffff9200002cf58 R14: 0000000080000000 R15: 0000000000000000
 timer_delete_sync kernel/time/timer.c:1629 [inline]
 del_timer_sync include/linux/timer.h:200 [inline]
 schedule_timeout+0x192/0x2d0 kernel/time/timer.c:2169
 rcu_gp_fqs_loop+0x30d/0x1590 kernel/rcu/tree.c:1667
 rcu_gp_kthread+0x9d/0x3b0 kernel/rcu/tree.c:1866
 kthread+0x2fa/0x390 kernel/kthread.c:388
 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
CPU: 0 PID: 20164 Comm: syz.6.3740 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
RIP: 0033:0x7f0a875bd6d0
Code: 83 c0 16 83 e0 f7 74 12 50 48 8d 3d 4a 2c 07 00 e8 65 65 f9 ff 0f 1f 44 00 00 c3 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 <83> ff 21 74 0b c3 66 2e 0f 1f 84 00 00 00 00 00 55 53 48 89 f3 48
RSP: 002b:00007f0a88511b38 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 00007f0a87825fa8 RCX: 00007f0a8759e159
RDX: 00007f0a88511b40 RSI: 00007f0a88511c70 RDI: 0000000000000021
RBP: 00007f0a87825fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f0a87826038 R14: 00007ffcf0c4a890 R15: 00007ffcf0c4a978
FS:  00007f0a885126c0 GS:  0000000000000000