rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P4355/1:b..l P4467/1:b..l
(detected by 1, t=10502 jiffies, g=36989, q=87 ncpus=2)
task:udevd state:R running task stack:23040 pid:4467 ppid:3638 flags:0x00004002
Call Trace:
context_switch kernel/sched/core.c:5244 [inline]
__schedule+0x10ec/0x40b0 kernel/sched/core.c:6561
preempt_schedule_irq+0xb1/0x150 kernel/sched/core.c:6873
irqentry_exit+0x63/0x70 kernel/entry/common.c:439
asm_sysvec_reschedule_ipi+0x16/0x20 arch/x86/include/asm/idtentry.h:696
RIP: 0010:lock_is_held_type+0x13a/0x190 kernel/locking/lockdep.c:5710
Code: 75 40 48 c7 04 24 00 00 00 00 9c 8f 04 24 f7 04 24 00 02 00 00 75 46 41 f7 c5 00 02 00 00 74 01 fb 65 48 8b 04 25 28 00 00 00 <48> 3b 44 24 08 75 3c 89 e8 48 83 c4 10 5b 41 5c 41 5d 41 5e 41 5f
RSP: 0018:ffffc9000497f890 EFLAGS: 00000206
RAX: 0c4c34c663a16a00 RBX: ffff8880254cbb80 RCX: 0c4c34c663a16a00
RDX: 0000000000000000 RSI: ffffffff8a8c1700 RDI: ffffffff8adef760
RBP: 0000000000000001 R08: dffffc0000000000 R09: fffff5200011178a
R10: fffff5200011178a R11: 1ffff92000111789 R12: 0000000000000002
R13: 0000000000000246 R14: ffffffff8cb2aca0 R15: ffff8880254cc6b0
hlist_bl_first_rcu include/linux/rculist_bl.h:24 [inline]
__d_lookup+0x195/0x7c0 fs/dcache.c:2492
d_lookup+0x21/0x60 fs/dcache.c:2439
lookup_open fs/namei.c:3412 [inline]
open_last_lookups fs/namei.c:3558 [inline]
path_openat+0x8dc/0x2e70 fs/namei.c:3788
do_filp_open+0x1c1/0x3c0 fs/namei.c:3818
do_sys_openat2+0x142/0x490 fs/open.c:1318
do_sys_open fs/open.c:1334 [inline]
__do_sys_openat fs/open.c:1350 [inline]
__se_sys_openat fs/open.c:1345 [inline]
__x64_sys_openat+0x135/0x160 fs/open.c:1345
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f621e0a7407
RSP: 002b:00007ffdf597ea10 EFLAGS: 00000202 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f621e745880 RCX: 00007f621e0a7407
RDX: 0000000000080241 RSI: 00007ffdf597ef70 RDI: ffffffffffffff9c
RBP: 0000000000000004 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000000001b6 R11: 0000000000000202 R12: 000055d753206dfc
R13: 000055d753206dfc R14: 0000000000000001 R15: 000055d753221140
task:kworker/u4:7 state:R running task stack:23432 pid:4355 ppid:2 flags:0x00004000
Workqueue: bat_events batadv_nc_worker
Call Trace:
context_switch kernel/sched/core.c:5244 [inline]
__schedule+0x10ec/0x40b0 kernel/sched/core.c:6561
preempt_schedule_irq+0xb1/0x150 kernel/sched/core.c:6873
irqentry_exit+0x63/0x70 kernel/entry/common.c:439
asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691
RIP: 0010:lock_acquire+0x20f/0x490 kernel/locking/lockdep.c:5666
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 44 3d 00 00 00 00 00 66 43 c7 44 3d 09 00 00 43 c6 44 3d 0b
RSP: 0018:ffffc900041a7ac0 EFLAGS: 00000206
RAX: 0000000000000001 RBX: 0000000000000000 RCX: 5de9bf7b8dfcf100
RDX: 0000000000000000 RSI: ffffffff8a8c1700 RDI: ffffffff8adef760
RBP: ffffc900041a7bc8 R08: dffffc0000000000 R09: fffffbfff215c449
R10: fffffbfff215c449 R11: 1ffffffff215c448 R12: 0000000000000000
R13: 1ffff92000834f64 R14: 0000000000000246 R15: dffffc0000000000
rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
rcu_read_lock include/linux/rcupdate.h:791 [inline]
batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:408 [inline]
batadv_nc_worker+0xeb/0x600 net/batman-adv/network-coding.c:719
process_one_work+0x898/0x1160 kernel/workqueue.c:2292
worker_thread+0xaa2/0x1250 kernel/workqueue.c:2439
kthread+0x29d/0x330 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
rcu: rcu_preempt kthread starved for 10554 jiffies! g36989 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:27840 pid:16 ppid:2 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5244 [inline]
__schedule+0x10ec/0x40b0 kernel/sched/core.c:6561
schedule+0xb9/0x180 kernel/sched/core.c:6637
schedule_timeout+0x15c/0x280 kernel/time/timer.c:2167
rcu_gp_fqs_loop+0x2f2/0x1310 kernel/rcu/tree.c:1706
rcu_gp_kthread+0x95/0x380 kernel/rcu/tree.c:1905
kthread+0x29d/0x330 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 7547 Comm: syz.9.706 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
RIP: 0010:mark_held_locks kernel/locking/lockdep.c:4218 [inline]
RIP: 0010:__trace_hardirqs_on_caller kernel/locking/lockdep.c:4248 [inline]
RIP: 0010:lockdep_hardirqs_on_prepare+0x1d8/0x760 kernel/locking/lockdep.c:4315
Code: 8a e8 0c 23 b5 08 65 ff 05 c5 b4 9f 7e 49 8d 9e d8 0a 00 00 49 89 de 49 c1 ee 03 48 ba 00 00 00 00 00 fc ff df 41 0f b6 04 16 <84> c0 0f 85 28 04 00 00 83 3b 00 0f 8e e9 00 00 00 48 8b 44 24 10
RSP: 0018:ffffc90004defe40 EFLAGS: 00000802
RAX: 0000000000000000 RBX: ffff888024758ad8 RCX: 4bad613e9337b000
RDX: dffffc0000000000 RSI: ffffffff8a8c1260 RDI: ffffffff8adef760
RBP: ffffc90004defef0 R08: dffffc0000000000 R09: fffffbfff1c3ed56
R10: fffffbfff1c3ed56 R11: 1ffffffff1c3ed55 R12: 0000000000000000
R13: 0000000000000000 R14: 1ffff110048eb15b R15: 0000000000000000
FS: 00007febea3626c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f7d70a61d58 CR3: 000000005c1e1000 CR4: 00000000003506f0
DR0: ffffffffffffffff DR1: 00000000000001f8 DR2: 0000000000000083
DR3: ffffffffefffff15 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
trace_hardirqs_on+0x34/0x40 kernel/trace/trace_preemptirq.c:49
syscall_enter_from_user_mode+0x21/0x80 kernel/entry/common.c:117
do_syscall_64+0x24/0xa0 arch/x86/entry/common.c:77
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7febe952b099
Code: 64 c7 00 16 00 00 00 b8 ff ff ff ff c3 0f 1f 40 00 90 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 c7 c0 0f 00 00 00 0f 05 <0f> 1f 80 00 00 00 00 48 81 ec 48 01 00 00 49 89 d0 64 48 8b 04 25
RSP: 002b:00007febea361b40 EFLAGS: 00000206 ORIG_RAX: 000000000000000f
RAX: ffffffffffffffda RBX: 00007febe97e6098 RCX: 00007febe952b099
RDX: 00007febea361b40 RSI: 00007febea361c70 RDI: 0000000000000021
RBP: 00007febe97e6090 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 00007febe97e6128 R14: 00007ffe903db620 R15: 00007ffe903db708