rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P11840/1:b..l P1085/1:b..l
rcu: (detected by 0, t=10503 jiffies, g=51485, q=56 ncpus=2)
task:kworker/u4:5 state:R running task stack:22096 pid:1085 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:ffffc9000485fa40 EFLAGS: 00000206
RAX: 0000000000000001 RBX: 0000000000000000 RCX: 2987785320b51100
RDX: 0000000000000000 RSI: ffffffff8aaacc20 RDI: ffffffff8afc70c0
RBP: ffffc9000485fb48 R08: dffffc0000000000 R09: 1ffffffff21b4aa0
R10: dffffc0000000000 R11: fffffbfff21b4aa1 R12: 1ffff9200090bf54
R13: ffffffff8cd2fc20 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.3.2131 state:R running task stack:24944 pid:11840 ppid:5795 flags:0x00004006
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
unwind_next_frame+0x200f/0x2970 arch/x86/kernel/unwind_orc.c:672
arch_stack_walk+0x144/0x190 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
save_stack+0xf7/0x1f0 mm/page_owner.c:128
__reset_page_owner+0x4e/0x190 mm/page_owner.c:149
reset_page_owner include/linux/page_owner.h:24 [inline]
free_pages_prepare mm/page_alloc.c:1154 [inline]
free_unref_page_prepare+0x7ce/0x8e0 mm/page_alloc.c:2336
free_unref_page_list+0xbe/0x860 mm/page_alloc.c:2475
release_pages+0x1fa0/0x2220 mm/swap.c:1022
__folio_batch_release+0x71/0xe0 mm/swap.c:1042
folio_batch_release include/linux/pagevec.h:83 [inline]
shmem_undo_range+0x5d0/0x1a40 mm/shmem.c:1027
shmem_truncate_range mm/shmem.c:1136 [inline]
shmem_evict_inode+0x273/0xa70 mm/shmem.c:1265
evict+0x486/0x870 fs/inode.c:705
__dentry_kill+0x431/0x650 fs/dcache.c:611
shrink_dentry_list+0x39f/0x6a0 fs/dcache.c:1206
shrink_dcache_parent+0xac/0x3c0 fs/dcache.c:-1
do_one_tree+0x23/0xe0 fs/dcache.c:1686
shrink_dcache_for_umount+0x69/0x110 fs/dcache.c:1703
generic_shutdown_super+0x67/0x2b0 fs/super.c:665
kill_anon_super fs/super.c:1303 [inline]
kill_litter_super+0x76/0xb0 fs/super.c:1313
deactivate_locked_super+0x97/0x100 fs/super.c:481
cleanup_mnt+0x429/0x4c0 fs/namespace.c:1250
task_work_run+0x1ce/0x250 kernel/task_work.c:239
exit_task_work include/linux/task_work.h:43 [inline]
do_exit+0x90b/0x23c0 kernel/exit.c:883
do_group_exit+0x21b/0x2d0 kernel/exit.c:1024
get_signal+0x12fc/0x1400 kernel/signal.c:2902
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: 0033:0x7f65d7bc14a5
RSP: 002b:00007f65d8acdf80 EFLAGS: 00000293 ORIG_RAX: 00000000000000e6
RAX: fffffffffffffdfc RBX: 00007f65d7dc5fa0 RCX: 00007f65d7bc14a5
RDX: 00007f65d8acdfc0 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007f65d7c11e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000
R13: 00007f65d7dc6038 R14: 00007f65d7dc5fa0 R15: 00007ffe5fd29ca8
rcu: rcu_preempt kthread starved for 5441 jiffies! g51485 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:27112 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: 0 PID: 12141 Comm: syz.5.2218 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0033:0x7f56c8f8ebe7
Code: ff ff 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
RSP: 002b:00007f56c9ddc0e8 EFLAGS: 00000246
RAX: 00000000000000ca RBX: 00007f56c91c6098 RCX: 00007f56c8f8ebe9
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f56c91c6098
RBP: 00007f56c91c6090 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f56c91c6128 R14: 00007ffcafc998e0 R15: 00007ffcafc999c8
FS: 00007f56c9ddc6c0 GS: 0000000000000000