rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P13973/1:b..l P29997/1:b..l
rcu: (detected by 0, t=10502 jiffies, g=221649, q=153 ncpus=2)
task:udevadm state:R running task stack:24360 pid:29997 ppid:26927 flags:0x00004002
Call Trace:
context_switch kernel/sched/core.c:5381 [inline]
__schedule+0x15ae/0x4660 kernel/sched/core.c:6700
preempt_schedule_common+0x82/0xc0 kernel/sched/core.c:6867
preempt_schedule+0xc0/0xd0 kernel/sched/core.c:6891
preempt_schedule_thunk+0x1a/0x30 arch/x86/entry/thunk_64.S:45
__raw_spin_unlock include/linux/spinlock_api_smp.h:143 [inline]
_raw_spin_unlock+0x3a/0x40 kernel/locking/spinlock.c:186
spin_unlock include/linux/spinlock.h:391 [inline]
finish_fault+0x8a3/0xce0 mm/memory.c:4508
do_cow_fault mm/memory.c:4683 [inline]
do_fault mm/memory.c:4777 [inline]
do_pte_missing mm/memory.c:3689 [inline]
handle_pte_fault mm/memory.c:5047 [inline]
__handle_mm_fault mm/memory.c:5188 [inline]
handle_mm_fault+0x2d5b/0x4a50 mm/memory.c:5353
do_user_addr_fault+0x736/0x12d0 arch/x86/mm/fault.c:1371
handle_page_fault arch/x86/mm/fault.c:1463 [inline]
exc_page_fault+0x64/0x100 arch/x86/mm/fault.c:1516
asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:608
RIP: 0033:0x7efefca078ec
RSP: 002b:00007ffdadfa4da0 EFLAGS: 00010202
RAX: 00007efefc214308 RBX: 00007efefc2c90c0 RCX: 00007efefc28c988
RDX: 00007efefc581ee0 RSI: 00007efefc706028 RDI: 00007efefc2c9fc0
RBP: 00007ffdadfa4ec0 R08: 00007efefc2c9180 R09: 00007efefc2c9fc0
R10: 00007efefc9f9580 R11: 0000000000000000 R12: 00007ffdadfa4e50
R13: 00007ffdadfa4e50 R14: 00007efefc9f9580 R15: 00007efefc200000
task:kworker/u4:24 state:R running task stack:21736 pid:13973 ppid:2 flags:0x00004000
Workqueue: bat_events batadv_iv_send_outstanding_bat_ogm_packet
Call Trace:
context_switch kernel/sched/core.c:5381 [inline]
__schedule+0x15ae/0x4660 kernel/sched/core.c:6700
preempt_schedule_irq+0xbf/0x150 kernel/sched/core.c:7010
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:__preempt_count_add arch/x86/include/asm/preempt.h:80 [inline]
RIP: 0010:rcu_is_watching+0x9/0xb0 kernel/rcu/tree.c:699
Code: e0 1a 09 48 c7 c7 00 86 13 8d 4c 89 f6 e8 5f 9e f3 02 e9 44 ff ff ff 66 2e 0f 1f 84 00 00 00 00 00 f3 0f 1e fa 41 57 41 56 53 <65> ff 05 68 01 93 7e e8 4b f6 1a 09 89 c3 83 f8 08 73 60 49 bf 00
RSP: 0018:ffffc90002ef79a0 EFLAGS: 00000202
RAX: ffffffff8a4e89f0 RBX: 0000000000000001 RCX: 0000000000000000
RDX: ffff88801f2e9e00 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc90002ef7b00 R08: dffffc0000000000 R09: 1ffffffff223cea0
R10: dffffc0000000000 R11: fffffbfff223cea1 R12: ffff8880601b6d00
R13: dffffc0000000000 R14: dffffc0000000000 R15: ffff888031995608
rcu_read_lock include/linux/rcupdate.h:787 [inline]
batadv_iv_ogm_slide_own_bcast_window net/batman-adv/bat_iv_ogm.c:759 [inline]
batadv_iv_ogm_schedule_buff net/batman-adv/bat_iv_ogm.c:839 [inline]
batadv_iv_ogm_schedule+0x479/0x1080 net/batman-adv/bat_iv_ogm.c:898
batadv_iv_send_outstanding_bat_ogm_packet+0x6bf/0x7d0 net/batman-adv/bat_iv_ogm.c:1795
process_one_work kernel/workqueue.c:2653 [inline]
process_scheduled_works+0xa60/0x1600 kernel/workqueue.c:2730
worker_thread+0xa5e/0xfe0 kernel/workqueue.c:2811
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
rcu: rcu_preempt kthread timer wakeup didn't happen for 10540 jiffies! g221649 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: Possible timer handling issue on cpu=0 timer-softirq=245493
rcu: rcu_preempt kthread starved for 10541 jiffies! g221649 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:26856 pid:17 ppid:2 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5381 [inline]
__schedule+0x15ae/0x4660 kernel/sched/core.c:6700
schedule+0xbd/0x170 kernel/sched/core.c:6774
schedule_timeout+0x188/0x2d0 kernel/time/timer.c:2168
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
rcu: Stack dump where RCU GP kthread last ran:
CPU: 0 PID: 29992 Comm: syz.4.6279 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
RIP: 0010:pv_native_safe_halt+0xf/0x10 arch/x86/kernel/paravirt.c:148
Code: 7c 1d 02 c3 cc cc cc cc cc cc cc f3 0f 1e fa 0f 0b 66 2e 0f 1f 84 00 00 00 00 00 f3 0f 1e fa 66 90 0f 00 2d 43 a7 3c 00 fb f4 66 0f 1f 00 55 41 57 41 56 41 54 53 50 8b 2f eb 2c 89 cb 80 f9
RSP: 0018:ffffc900037ff5f8 EFLAGS: 000002c7
RAX: ffffffff813a9538 RBX: 0000000000000003 RCX: 0000000000080000
RDX: ffffc90012819000 RSI: 0000000000046486 RDI: 0000000000046487
RBP: ffffc900037ff6d0 R08: ffffffff911e763f R09: 1ffffffff223cec7
R10: dffffc0000000000 R11: fffffbfff223cec8 R12: dffffc0000000000
R13: 0000000000000200 R14: 0000000000000003 R15: 1ffff920006ffec4
FS: 00007f6939fd56c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000020000000b038 CR3: 000000004435d000 CR4: 00000000003506f0
Call Trace:
arch_safe_halt arch/x86/include/asm/paravirt.h:108 [inline]
kvm_wait+0x23d/0x2a0 arch/x86/kernel/kvm.c:1058
pv_wait arch/x86/include/asm/paravirt.h:598 [inline]
pv_wait_head_or_lock kernel/locking/qspinlock_paravirt.h:470 [inline]
__pv_queued_spin_lock_slowpath+0x613/0x9c0 kernel/locking/qspinlock.c:511
pv_queued_spin_lock_slowpath arch/x86/include/asm/paravirt.h:586 [inline]
queued_spin_lock_slowpath arch/x86/include/asm/qspinlock.h:51 [inline]
queued_spin_lock include/asm-generic/qspinlock.h:114 [inline]
do_raw_spin_lock+0x23e/0x2b0 kernel/locking/spinlock_debug.c:115
spin_lock_bh include/linux/spinlock.h:356 [inline]
lock_sock_nested+0x6a/0x100 net/core/sock.c:3547
lock_sock include/net/sock.h:1780 [inline]
tipc_sendstream+0x47/0x70 net/tipc/socket.c:1550
sock_sendmsg_nosec net/socket.c:730 [inline]
__sock_sendmsg net/socket.c:745 [inline]
____sys_sendmsg+0x61b/0x980 net/socket.c:2595
___sys_sendmsg+0x2a6/0x360 net/socket.c:2649
__sys_sendmmsg+0x2ca/0x510 net/socket.c:2735
__do_sys_sendmmsg net/socket.c:2764 [inline]
__se_sys_sendmmsg net/socket.c:2761 [inline]
__x64_sys_sendmmsg+0xa0/0xb0 net/socket.c:2761
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: 0033:0x7f693bd9de59
Code: 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 01 48
RSP: 002b:00007f6939fd5028 EFLAGS: 00000246 ORIG_RAX: 0000000000000133
RAX: ffffffffffffffda RBX: 00007f693c026090 RCX: 00007f693bd9de59
RDX: 04000000000001cd RSI: 0000200000005280 RDI: 0000000000000008
RBP: 00007f693be33e6f R08: 0000000000000000 R09: 0000000000000000
R10: 000000001008c811 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f693c026128 R14: 00007f693c026090 R15: 00007ffd936cc638