rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P5200/1:b..l
(detected by 0, t=10661 jiffies, g=12581, q=3573)
task:udevd state:R running task stack:27200 pid: 5200 ppid: 3547 flags:0x00004002
Call Trace:
context_switch kernel/sched/core.c:5030 [inline]
__schedule+0x11b8/0x43b0 kernel/sched/core.c:6376
preempt_schedule_common+0x82/0xd0 kernel/sched/core.c:6552
preempt_schedule+0xa7/0xb0 kernel/sched/core.c:6577
preempt_schedule_thunk+0x16/0x18 arch/x86/entry/thunk_64.S:34
__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:161 [inline]
_raw_spin_unlock_irqrestore+0xf6/0x100 kernel/locking/spinlock.c:194
spin_unlock_irqrestore include/linux/spinlock.h:418 [inline]
__wake_up_common_lock kernel/sched/wait.c:140 [inline]
__wake_up_sync_key+0x11b/0x180 kernel/sched/wait.c:205
sock_def_readable+0x136/0x250 net/core/sock.c:3093
unix_dgram_sendmsg+0x11ed/0x1890 net/unix/af_unix.c:1935
sock_sendmsg_nosec net/socket.c:704 [inline]
__sock_sendmsg net/socket.c:716 [inline]
sock_write_iter+0x29c/0x380 net/socket.c:1079
call_write_iter include/linux/fs.h:2172 [inline]
new_sync_write fs/read_write.c:507 [inline]
vfs_write+0x712/0xd00 fs/read_write.c:594
ksys_write+0x14d/0x250 fs/read_write.c:647
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: 0033:0x7f5bbd8c6bf2
RSP: 002b:00007ffea0a256d8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f5bbd8c6bf2
RDX: 0000000000000000 RSI: 00007ffea0a2572f RDI: 000000000000000a
RBP: 00007ffea0a2572f R08: 0000000000000001 R09: 0000000000000000
R10: 000000000000010f R11: 0000000000000246 R12: 000000000000000a
R13: 00007f5bbd79bae0 R14: 0000000000000000 R15: 0000557ea4eff910
rcu: rcu_preempt kthread timer wakeup didn't happen for 6755 jiffies! g12581 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: Possible timer handling issue on cpu=1 timer-softirq=3954
rcu: rcu_preempt kthread starved for 6756 jiffies! g12581 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:27584 pid: 15 ppid: 2 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5030 [inline]
__schedule+0x11b8/0x43b0 kernel/sched/core.c:6376
schedule+0x11b/0x1e0 kernel/sched/core.c:6459
schedule_timeout+0x15c/0x280 kernel/time/timer.c:1914
rcu_gp_fqs_loop+0x29e/0x11b0 kernel/rcu/tree.c:1972
rcu_gp_kthread+0x98/0x350 kernel/rcu/tree.c:2145
kthread+0x436/0x520 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
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: 3097 Comm: kworker/u4:5 Not tainted 5.15.181-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/19/2025
Workqueue: bat_events batadv_tt_purge
RIP: 0010:rcu_dynticks_curr_cpu_in_eqs kernel/rcu/tree.c:331 [inline]
RIP: 0010:rcu_is_watching+0x22/0xa0 kernel/rcu/tree.c:1123
Code: 08 0f 1f 80 00 00 00 00 41 57 41 56 53 65 ff 05 1c d7 9e 7e e8 5f a4 3d 08 89 c3 83 f8 08 73 5c 49 bf 00 00 00 00 00 fc ff df <4c> 8d 34 dd 10 e8 ba 8b 4c 89 f0 48 c1 e8 03 42 80 3c 38 00 74 08
RSP: 0018:ffffc90000dd0b40 EFLAGS: 00000097
RAX: 0000000000000001 RBX: 0000000000000001 RCX: 4c1790e1d713ec00
RDX: 0000000000000000 RSI: ffffffff8a59a2a0 RDI: ffffffff8a59a260
RBP: ffffc90000dd0c70 R08: dffffc0000000000 R09: fffffbfff1ad155e
R10: fffffbfff1ad155e R11: 1ffffffff1ad155d R12: ffff88807f31f2e8
R13: dffffc0000000000 R14: ffff88807f31f000 R15: dffffc0000000000
FS: 0000000000000000(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f9119e35ab8 CR3: 000000005dd0a000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
trace_lock_release include/trace/events/lock.h:58 [inline]
lock_release+0xba/0x870 kernel/locking/lockdep.c:5634
rcu_read_unlock include/linux/rcupdate.h:772 [inline]
advance_sched+0x7d0/0x940 net/sched/sch_taprio.c:771
__run_hrtimer kernel/time/hrtimer.c:1690 [inline]
__hrtimer_run_queues+0x53d/0xc40 kernel/time/hrtimer.c:1754
hrtimer_interrupt+0x3bb/0x8d0 kernel/time/hrtimer.c:1816
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1097 [inline]
__sysvec_apic_timer_interrupt+0x137/0x4a0 arch/x86/kernel/apic/apic.c:1114
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline]
sysvec_apic_timer_interrupt+0x9b/0xc0 arch/x86/kernel/apic/apic.c:1108
asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:should_resched arch/x86/include/asm/preempt.h:103 [inline]
RIP: 0010:__local_bh_enable_ip+0x132/0x1b0 kernel/softirq.c:390
Code: 8a e8 82 e0 58 08 65 66 8b 05 0a 3b bb 7e 66 85 c0 75 54 bf 01 00 00 00 e8 5b fe 08 00 e8 76 7e 35 00 fb 65 8b 05 f6 11 ba 7e <85> c0 75 05 e8 a5 1c b8 ff 48 c7 04 24 0e 36 e0 45 4b c7 04 37 00
RSP: 0018:ffffc9000c9cfb20 EFLAGS: 00000282
RAX: 0000000080000000 RBX: 0000000000000201 RCX: 4c1790e1d713ec00
RDX: dffffc0000000000 RSI: ffffffff8a0b0fc0 RDI: ffffffff8a59a2c0
RBP: ffffc9000c9cfba8 R08: dffffc0000000000 R09: fffffbfff1ff323d
R10: fffffbfff1ff323d R11: 1ffffffff1ff323c R12: ffffffff8979d514
R13: dffffc0000000000 R14: dffffc0000000000 R15: 1ffff92001939f64
spin_unlock_bh include/linux/spinlock.h:408 [inline]
batadv_tt_global_purge net/batman-adv/translation-table.c:2314 [inline]
batadv_tt_purge+0x4d4/0x9f0 net/batman-adv/translation-table.c:3583
process_one_work+0x863/0x1000 kernel/workqueue.c:2310
worker_thread+0xaa8/0x12a0 kernel/workqueue.c:2457
kthread+0x436/0x520 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287