rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P5782/2:b..l P58/1:b..l
rcu: (detected by 1, t=10503 jiffies, g=12169, q=942 ncpus=2)
task:kworker/u4:4 state:R running task stack:23384 pid:58 ppid:2 flags:0x00004000
Workqueue: bat_events batadv_nc_worker
Call Trace:
context_switch kernel/sched/core.c:5380 [inline]
__schedule+0x14d2/0x44d0 kernel/sched/core.c:6699
preempt_schedule_irq+0xb5/0x140 kernel/sched/core.c:7009
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:lock_acquire+0x1f2/0x410 kernel/locking/lockdep.c:5758
Code: 00 9c 8f 84 24 80 00 00 00 f6 84 24 81 00 00 00 02 0f 85 f5 00 00 00 41 f7 c6 00 02 00 00 74 01 fb 48 c7 44 24 60 0e 36 e0 45 <4b> c7 04 3c 00 00 00 00 66 43 c7 44 3c 09 00 00 43 c6 44 3c 0b 00
RSP: 0018:ffffc90001597a40 EFLAGS: 00000206
RAX: 0000000000000001 RBX: 0000000000000000 RCX: f141e2bbd04e1b00
RDX: 0000000000000000 RSI: ffffffff8aaacb40 RDI: ffffffff8afc66c0
RBP: ffffc90001597b48 R08: dffffc0000000000 R09: 1ffffffff21b46a0
R10: dffffc0000000000 R11: fffffbfff21b46a1 R12: 1ffff920002b2f54
R13: ffffffff8cd2fbe0 R14: 0000000000000246 R15: dffffc0000000000
rcu_lock_acquire include/linux/rcupdate.h:334 [inline]
rcu_read_lock include/linux/rcupdate.h:786 [inline]
batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:408 [inline]
batadv_nc_worker+0xef/0x610 net/batman-adv/network-coding.c:719
process_one_work kernel/workqueue.c:2634 [inline]
process_scheduled_works+0xa45/0x15b0 kernel/workqueue.c:2711
worker_thread+0xa55/0xfc0 kernel/workqueue.c:2792
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:syz-execprog state:R running task stack:24232 pid:5782 ppid:5781 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5380 [inline]
__schedule+0x14d2/0x44d0 kernel/sched/core.c:6699
preempt_schedule_common+0x82/0xc0 kernel/sched/core.c:6866
preempt_schedule+0xab/0xc0 kernel/sched/core.c:6890
preempt_schedule_thunk+0x1a/0x30 arch/x86/entry/thunk_64.S:45
__local_bh_enable_ip+0x13f/0x1c0 kernel/softirq.c:413
local_bh_enable include/linux/bottom_half.h:33 [inline]
rcu_read_unlock_bh include/linux/rcupdate.h:856 [inline]
__dev_queue_xmit+0x1449/0x35a0 net/core/dev.c:4440
dev_queue_xmit include/linux/netdevice.h:3113 [inline]
neigh_hh_output include/net/neighbour.h:526 [inline]
neigh_output include/net/neighbour.h:540 [inline]
ip_finish_output2+0xcd3/0x11d0 net/ipv4/ip_output.c:235
dst_output include/net/dst.h:467 [inline]
ip_local_out net/ipv4/ip_output.c:129 [inline]
__ip_queue_xmit+0x10aa/0x1a10 net/ipv4/ip_output.c:535
__tcp_transmit_skb+0x1c97/0x32a0 net/ipv4/tcp_output.c:1422
tcp_transmit_skb net/ipv4/tcp_output.c:1440 [inline]
tcp_write_xmit+0x14ee/0x6270 net/ipv4/tcp_output.c:2767
__tcp_push_pending_frames+0x97/0x340 net/ipv4/tcp_output.c:2952
tcp_sendmsg_locked+0x4286/0x4af0 net/ipv4/tcp.c:1312
tcp_sendmsg+0x2f/0x50 net/ipv4/tcp.c:1344
sock_sendmsg_nosec net/socket.c:730 [inline]
__sock_sendmsg net/socket.c:745 [inline]
sock_write_iter+0x2bb/0x3f0 net/socket.c:1160
call_write_iter include/linux/fs.h:2018 [inline]
new_sync_write fs/read_write.c:491 [inline]
vfs_write+0x43b/0x940 fs/read_write.c:584
ksys_write+0x147/0x250 fs/read_write.c:637
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x40dd0e
RSP: 002b:000000c00313f3e8 EFLAGS: 00000206 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000000006 RCX: 000000000040dd0e
RDX: 00000000000004b0 RSI: 000000c006a5e5d0 RDI: 0000000000000006
RBP: 000000c00313f428 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 000000c00313f558
R13: 00000000000005ee R14: 000000c00245cfc0 R15: 000000c006a5e000
rcu: rcu_preempt kthread starved for 10567 jiffies! g12169 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:26568 pid:17 ppid:2 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5380 [inline]
__schedule+0x14d2/0x44d0 kernel/sched/core.c:6699
schedule+0xbd/0x170 kernel/sched/core.c:6773
schedule_timeout+0x160/0x280 kernel/time/timer.c:2167
rcu_gp_fqs_loop+0x302/0x1560 kernel/rcu/tree.c:1667
rcu_gp_kthread+0x99/0x380 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: 1 PID: 6042 Comm: syz.2.33 Not tainted 6.6.102-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:160 [inline]
RIP: 0010:_raw_spin_unlock_irq+0x29/0x50 kernel/locking/spinlock.c:202
Code: 00 f3 0f 1e fa 53 48 89 fb 48 83 c7 18 48 8b 74 24 08 e8 aa 8f f0 f6 48 89 df e8 c2 61 f1 f6 e8 7d fd 14 f7 fb bf 01 00 00 00 12 7a e4 f6 65 8b 05 33 c9 8c 75 85 c0 74 02 5b c3 e8 10 ab 89
RSP: 0018:ffffc900037e7c98 EFLAGS: 00000282
RAX: 9d41bdb587667200 RBX: ffff888030528940 RCX: 9d41bdb587667200
RDX: dffffc0000000000 RSI: ffffffff8aaab9c0 RDI: 0000000000000001
RBP: ffff888030528bd8 R08: ffffffff8e4a882f R09: 1ffffffff1c95105
R10: dffffc0000000000 R11: fffffbfff1c95106 R12: 1ffff110060a517b
R13: 0000000000000011 R14: dffffc0000000000 R15: 0000000000000000
FS: 00007fb247e4d6c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 000000007b460000 CR4: 00000000003506e0
Call Trace:
spin_unlock_irq include/linux/spinlock.h:401 [inline]
get_signal+0x11f5/0x1400 kernel/signal.c:2905
arch_do_signal_or_restart+0x96/0x780 arch/x86/kernel/signal.c:310
exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174
exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:210
__syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline]
syscall_exit_to_user_mode+0x1a/0x50 kernel/entry/common.c:302
do_syscall_64+0x61/0xb0 arch/x86/entry/common.c:87
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fb246f8ebe9
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:00007fb247e4d0e8 EFLAGS: 00000246
RAX: fffffffffffffffc RBX: 00007fb2471b5fa8 RCX: 00007fb246f8ebe9
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007fb2471b5fa8
RBP: 00007fb2471b5fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fb2471b6038 R14: 00007fff97121c60 R15: 00007fff97121d48
sched: RT throttling activated