rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P8307/1:b..l..
rcu: (detected by 0, t=10502 jiffies, g=52661, q=536 ncpus=1)
task:syz.7.471 state:R running task stack:26152 pid:8307 tgid:8305 ppid:6330 task_flags:0x40054c flags:0x00080001
Call Trace:
context_switch kernel/sched/core.c:5583 [inline]
__schedule+0x17dd/0x5830 kernel/sched/core.c:7382
preempt_schedule_irq+0x4b/0x90 kernel/sched/core.c:7662
irqentry_exit_to_kernel_mode include/linux/irq-entry-common.h:543 [inline]
irqentry_exit+0x14f/0x9b0 kernel/entry/common.c:154
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674
RIP: 0010:lock_acquire+0x232/0x350 kernel/locking/lockdep.c:5947
Code: ff ff ff e8 d0 aa 60 0a f7 44 24 10 00 02 00 00 0f 84 38 ff ff ff 65 48 8b 05 d2 34 3d 13 48 3b 44 24 50 75 33 fb 48 83 c4 58 <5b> 41 5c 41 5d 41 5e 41 5f 5d c3 cc cc cc cc cc 48 8d 3d c7 19 1d
RSP: 0018:ffffc90003c7ed40 EFLAGS: 00000292
RAX: 4c8ef2a019ee9100 RBX: 0000000000000000 RCX: 0000000000000046
RDX: 00000000105209fd RSI: ffffffff8e9347d2 RDI: ffffffff8c8ea380
RBP: ffff888028a31f40 R08: ffffffff8178798f R09: 0000000000000000
R10: ffffc90003c7ee78 R11: ffffffff81b3a670 R12: ffffffff9015a420
R13: 0000000000000002 R14: 0000000000000000 R15: 0000000000000246
rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
rcu_read_lock include/linux/rcupdate.h:849 [inline]
class_rcu_constructor include/linux/rcupdate.h:1216 [inline]
unwind_next_frame+0xac/0x2550 arch/x86/kernel/unwind_orc.c:495
arch_stack_walk+0x11b/0x150 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122
save_stack+0x122/0x230 mm/page_owner.c:183
__reset_page_owner+0x73/0x2a0 mm/page_owner.c:338
reset_page_owner include/linux/page_owner.h:26 [inline]
__free_pages_prepare mm/page_alloc.c:1403 [inline]
free_unref_folios+0xdc6/0x14e0 mm/page_alloc.c:3017
folios_put_refs+0x9e9/0xb30 mm/folio.c:1039
folio_batch_release include/linux/folio_batch.h:101 [inline]
shmem_undo_range+0x55a/0x1730 mm/shmem.c:1372
shmem_truncate_range mm/shmem.c:1508 [inline]
shmem_evict_inode+0x240/0xb00 mm/shmem.c:1652
evict+0x624/0xb50 fs/inode.c:822
dentry_kill+0x1b9/0x910 fs/dcache.c:864
finish_dput+0x1a/0x260 fs/dcache.c:1039
__fput+0x65b/0xa40 fs/file_table.c:521
task_work_run+0x1d9/0x260 kernel/task_work.c:233
exit_task_work include/linux/task_work.h:40 [inline]
do_exit+0x705/0x2360 kernel/exit.c:980
do_group_exit+0x22d/0x2f0 kernel/exit.c:1123
get_signal+0x136a/0x1430 kernel/signal.c:3113
arch_do_signal_or_restart+0xbb/0x860 arch/x86/kernel/signal.c:337
__exit_to_user_mode_loop kernel/entry/common.c:66 [inline]
exit_to_user_mode_loop+0x10e/0x770 kernel/entry/common.c:101
__exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline]
syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:230 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:343 [inline]
do_syscall_64+0x328/0x520 arch/x86/entry/syscall_64.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fc98059f559
RSP: 002b:00007fc9813f90e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 00007fc980826098 RCX: 00007fc98059f559
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007fc980826098
RBP: 00007fc980826090 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fc980826128 R14: 00007ffe115a5e80 R15: 00007ffe115a5f68
rcu: rcu_preempt kthread starved for 218 jiffies! g52661 f0x0 RCU_GP_WAIT_FQS(5) ->state=R ->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:27752 pid:17 tgid:17 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5583 [inline]
__schedule+0x17dd/0x5830 kernel/sched/core.c:7382
__schedule_loop kernel/sched/core.c:7459 [inline]
schedule+0x164/0x2b0 kernel/sched/core.c:7474
schedule_timeout+0x152/0x2c0 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x30c/0x1230 kernel/rcu/tree.c:2122
rcu_gp_kthread+0x9c/0x340 kernel/rcu/tree.c:2330
kthread+0x38b/0x480 kernel/kthread.c:436
ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
rcu: Stack dump where RCU GP kthread last ran:
CPU: 0 UID: 0 PID: 3233 Comm: kworker/R-bat_e Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/15/2026
Workqueue: bat_events batadv_tt_purge
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:211 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0x47/0x80 kernel/locking/spinlock.c:221
Code: f7 e8 9d 34 9d f5 f7 c3 00 02 00 00 74 05 e8 e0 dc c9 f5 9c 58 a9 00 02 00 00 75 29 f7 c3 00 02 00 00 74 01 fb bf 01 00 00 00 d4 28 8e f5 65 48 8b 05 ac c1 d9 08 48 85 c0 74 18 5b 41 5e c3
RSP: 0018:ffffc90000007b48 EFLAGS: 00000206
RAX: 0000000000000016 RBX: 0000000000000246 RCX: 8000000000000102
RDX: 0000000000000002 RSI: ffffffff8e6a8c20 RDI: 0000000000000001
RBP: ffffc90000007e48 R08: ffffffff91bdfabf R09: 1ffffffff237bf57
R10: dffffc0000000000 R11: fffffbfff237bf58 R12: 0000000000000246
R13: dffffc0000000000 R14: ffff88802af08000 R15: ffff88802ae14410
FS: 0000000000000000(0000) GS:ffff88812340b000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fba3caa9da2 CR3: 000000007ee16000 CR4: 00000000003526f0
Call Trace:
spin_unlock_irqrestore include/linux/spinlock.h:425 [inline]
dummy_timer+0x4967/0x4ce0 drivers/usb/gadget/udc/dummy_hcd.c:-1
__run_hrtimer kernel/time/hrtimer.c:2079 [inline]
__hrtimer_run_queues+0x3bc/0xa10 kernel/time/hrtimer.c:2136
hrtimer_run_softirq+0x1e3/0x2e0 kernel/time/hrtimer.c:2153
handle_softirqs+0x265/0x8d0 kernel/softirq.c:669
do_softirq+0x77/0xd0 kernel/softirq.c:569
__local_bh_enable_ip+0x100/0x140 kernel/softirq.c:473
spin_unlock_bh include/linux/spinlock.h:407 [inline]
batadv_tt_local_purge+0x277/0x300 net/batman-adv/translation-table.c:1798
batadv_tt_purge+0x35/0xa40 net/batman-adv/translation-table.c:4269
process_one_work kernel/workqueue.c:3495 [inline]
process_scheduled_works+0xc3d/0x1630 kernel/workqueue.c:3578
rescuer_thread+0x84a/0x12a0 kernel/workqueue.c:3803
kthread+0x38b/0x480 kernel/kthread.c:436
ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245