rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P4434/1:b..l P4306/1:b..l
(detected by 0, t=10502 jiffies, g=8489, q=333 ncpus=2)
task:kworker/u4:5 state:R running task stack:25728 pid:4306 ppid:2 flags:0x00004000
Workqueue: bat_events batadv_nc_worker
Call Trace:
context_switch kernel/sched/core.c:5244 [inline]
__schedule+0x10e9/0x40d0 kernel/sched/core.c:6561
preempt_schedule_notrace+0xca/0x110 kernel/sched/core.c:6823
preempt_schedule_notrace_thunk+0x16/0x18 arch/x86/entry/thunk_64.S:35
rcu_is_watching+0x76/0xa0 kernel/rcu/tree.c:722
rcu_read_lock include/linux/rcupdate.h:792 [inline]
batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:408 [inline]
batadv_nc_worker+0x108/0x600 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
task:udevd state:R running task stack:24064 pid:4434 ppid:3623 flags:0x00004002
Call Trace:
context_switch kernel/sched/core.c:5244 [inline]
__schedule+0x10e9/0x40d0 kernel/sched/core.c:6561
preempt_schedule_common+0x82/0xd0 kernel/sched/core.c:6730
preempt_schedule+0xa7/0xb0 kernel/sched/core.c:6754
preempt_schedule_thunk+0x16/0x18 arch/x86/entry/thunk_64.S:34
__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:160 [inline]
_raw_spin_unlock_irq+0x3c/0x40 kernel/locking/spinlock.c:202
spin_unlock_irq include/linux/spinlock.h:401 [inline]
loop_queue_work drivers/block/loop.c:894 [inline]
loop_queue_rq+0x9d9/0xac0 drivers/block/loop.c:1874
__blk_mq_issue_directly block/blk-mq.c:2631 [inline]
__blk_mq_try_issue_directly+0x4ab/0x7a0 block/blk-mq.c:2684
blk_mq_request_issue_directly block/blk-mq.c:2718 [inline]
blk_mq_plug_issue_direct+0x233/0x620 block/blk-mq.c:2738
blk_mq_flush_plug_list+0x7e7/0xd40 block/blk-mq.c:2838
__blk_flush_plug+0x3c6/0x440 block/blk-core.c:1163
blk_finish_plug+0x59/0x80 block/blk-core.c:1187
read_pages+0x646/0x840 mm/readahead.c:184
page_cache_ra_unbounded+0x690/0x770 mm/readahead.c:270
do_page_cache_ra mm/readahead.c:300 [inline]
force_page_cache_ra mm/readahead.c:331 [inline]
page_cache_sync_ra+0x3d7/0x490 mm/readahead.c:713
page_cache_sync_readahead include/linux/pagemap.h:1248 [inline]
filemap_get_pages mm/filemap.c:2665 [inline]
filemap_read+0x5ff/0x2f80 mm/filemap.c:2759
blkdev_read_iter+0x3d5/0x500 block/fops.c:614
call_read_iter include/linux/fs.h:2259 [inline]
new_sync_read fs/read_write.c:389 [inline]
vfs_read+0x434/0x920 fs/read_write.c:470
ksys_read+0x143/0x240 fs/read_write.c:613
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: 0033:0x7fb16fca7407
RSP: 002b:00007ffd1f25e630 EFLAGS: 00000202 ORIG_RAX: 0000000000000000
RAX: ffffffffffffffda RBX: 00007fb17038b880 RCX: 00007fb16fca7407
RDX: 0000000000000200 RSI: 00007fb17037f000 RDI: 0000000000000009
RBP: 000055f94d267000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 00000000000001f6
R13: 0000000000007e00 R14: 000055f94d270518 R15: 00007fb1704b239c
rcu: rcu_preempt kthread timer wakeup didn't happen for 10546 jiffies! g8489 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: Possible timer handling issue on cpu=0 timer-softirq=4882
rcu: rcu_preempt kthread starved for 10552 jiffies! g8489 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:28192 pid:16 ppid:2 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5244 [inline]
__schedule+0x10e9/0x40d0 kernel/sched/core.c:6561
schedule+0xb9/0x180 kernel/sched/core.c:6637
schedule_timeout+0x15c/0x280 kernel/time/timer.c:1965
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:
CPU: 0 PID: 4559 Comm: syz.2.59 Not tainted 6.1.138-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/19/2025
RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:160 [inline]
RIP: 0010:_raw_spin_unlock_irq+0x25/0x40 kernel/locking/spinlock.c:202
Code: f5 ff 0f 1f 00 53 48 89 fb 48 83 c7 18 48 8b 74 24 08 e8 4e 1b 4a f7 48 89 df e8 a6 e0 4a f7 e8 11 e3 6d f7 fb bf 01 00 00 00 b6 5d 3e f7 65 8b 05 b7 22 e9 75 85 c0 74 02 5b c3 e8 04 34 e7
RSP: 0018:ffffc90004f77bb8 EFLAGS: 00000286
RAX: f2e1470cb76b4400 RBX: ffff8880561c3780 RCX: f2e1470cb76b4400
RDX: dffffc0000000000 RSI: ffffffff8a6bfe00 RDI: 0000000000000001
RBP: ffff8880561c3a18 R08: dffffc0000000000 R09: ffffed100ac386f1
R10: ffffed100ac386f1 R11: 1ffff1100ac386f0 R12: 1ffff1100ac38743
R13: 0000000000000011 R14: dffffc0000000000 R15: 0000000000000000
FS: 00007f03543b16c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f5447382338 CR3: 000000001fb1d000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
spin_unlock_irq include/linux/spinlock.h:401 [inline]
get_signal+0x1163/0x1350 kernel/signal.c:2874
arch_do_signal_or_restart+0xb0/0x1230 arch/x86/kernel/signal.c:871
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:292 [inline]
syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:303
do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:87
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f035358e969
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:00007f03543b1038 EFLAGS: 00000246
RAX: fffffffffffffffc RBX: 00007f03537b5fa0 RCX: 00007f035358e969
RDX: 00000000000000fc RSI: 00002000000000c0 RDI: 0000000000000003
RBP: 00007f0353610ab1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f03537b5fa0 R15: 00007ffd96dc6b38