rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P4975/1:b..l P24565/1:b..l
rcu: (detected by 0, t=10502 jiffies, g=252929, q=1140 ncpus=1)
task:syz-executor state:R running task stack:23816 pid:24565 tgid:24565 ppid:24554 task_flags:0x400140 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5510 [inline]
__schedule+0x125c/0x6730 kernel/sched/core.c:7234
preempt_schedule_notrace+0x5f/0xd0 kernel/sched/core.c:7506
preempt_schedule_notrace_thunk+0x16/0x30 arch/x86/entry/thunk.S:13
rcu_is_watching+0x8e/0xc0 kernel/rcu/tree.c:753
rcu_read_lock include/linux/rcupdate.h:841 [inline]
class_rcu_constructor include/linux/rcupdate.h:1183 [inline]
unwind_next_frame+0x6fa/0x2090 arch/x86/kernel/unwind_orc.c:495
__unwind_start+0x3cd/0x7e0 arch/x86/kernel/unwind_orc.c:787
unwind_start arch/x86/include/asm/unwind.h:64 [inline]
arch_stack_walk+0x73/0xf0 arch/x86/kernel/stacktrace.c:24
stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122
save_stack+0x162/0x1e0 mm/page_owner.c:165
__reset_page_owner+0x84/0x190 mm/page_owner.c:320
reset_page_owner include/linux/page_owner.h:25 [inline]
__free_pages_prepare mm/page_alloc.c:1406 [inline]
__free_frozen_pages+0x79f/0x1090 mm/page_alloc.c:2950
qlink_free mm/kasan/quarantine.c:163 [inline]
qlist_free_all+0x47/0xf0 mm/kasan/quarantine.c:179
kasan_quarantine_reduce+0x1a0/0x1f0 mm/kasan/quarantine.c:286
__kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:350
kasan_slab_alloc include/linux/kasan.h:253 [inline]
slab_post_alloc_hook mm/slub.c:4584 [inline]
slab_alloc_node mm/slub.c:4917 [inline]
__do_kmalloc_node mm/slub.c:5333 [inline]
__kmalloc_noprof+0x2bf/0x820 mm/slub.c:5359
_kmalloc_noprof include/linux/slab.h:992 [inline]
_kzalloc_noprof include/linux/slab.h:1309 [inline]
tomoyo_encode2+0xfb/0x3c0 security/tomoyo/realpath.c:45
tomoyo_encode+0x29/0x50 security/tomoyo/realpath.c:80
tomoyo_realpath_from_path+0x18c/0x690 security/tomoyo/realpath.c:283
tomoyo_get_realpath security/tomoyo/file.c:151 [inline]
tomoyo_path_perm+0x276/0x460 security/tomoyo/file.c:827
security_inode_getattr+0x116/0x280 security/security.c:1895
vfs_getattr fs/stat.c:259 [inline]
vfs_statx_path fs/stat.c:299 [inline]
vfs_statx+0x11f/0x3f0 fs/stat.c:356
vfs_fstatat+0x77/0xe0 fs/stat.c:373
__do_sys_newfstatat+0x9d/0x120 fs/stat.c:538
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fa69b79c4da
RSP: 002b:00007ffddf1f2518 EFLAGS: 00000286 ORIG_RAX: 0000000000000106
RAX: ffffffffffffffda RBX: 00007fa69b83330a RCX: 00007fa69b79c4da
RDX: 00007ffddf1f2540 RSI: 00007ffddf1f25d0 RDI: 00000000ffffff9c
RBP: 00007ffddf1f25d0 R08: 00007ffddf1f35d0 R09: 00000000ffffffff
R10: 0000000000000100 R11: 0000000000000286 R12: 00007ffddf1f3660
R13: 00007fa69b83330a R14: 00000000001c5cda R15: 00007ffddf1f36a0
task:udevd state:R running task stack:23944 pid:4975 tgid:4975 ppid:1 task_flags:0x400140 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5510 [inline]
__schedule+0x125c/0x6730 kernel/sched/core.c:7234
preempt_schedule_irq+0x50/0x90 kernel/sched/core.c:7556
irqentry_exit_to_kernel_mode_preempt include/linux/irq-entry-common.h:468 [inline]
irqentry_exit_to_kernel_mode include/linux/irq-entry-common.h:539 [inline]
irqentry_exit+0x205/0xa00 kernel/entry/common.c:167
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674
RIP: 0010:lock_acquire+0x5e/0x370 kernel/locking/lockdep.c:5872
Code: 05 fb 4d 7e 12 83 f8 07 0f 87 da 00 00 00 48 0f a3 05 86 87 3c 0f 0f 82 ac 02 00 00 8b 35 4e bb 3c 0f 85 f6 0f 85 c7 00 00 00 <48> 8b 44 24 30 65 48 2b 05 9d 4d 7e 12 0f 85 ec 02 00 00 48 83 c4
RSP: 0018:ffffc90004ad77a8 EFLAGS: 00000206
RAX: 0000000000000046 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff8e18006a RDI: ffffffff8c401680
RBP: ffffffff8ebe8180 R08: 00000000217d2744 R09: 0000000000000007
R10: 0000000000000200 R11: 0000000000000000 R12: 0000000000000002
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
rcu_read_lock include/linux/rcupdate.h:840 [inline]
__page_table_check_zero+0x8b/0x410 mm/page_table_check.c:138
page_table_check_free include/linux/page_table_check.h:46 [inline]
__free_pages_prepare mm/page_alloc.c:1407 [inline]
__free_frozen_pages+0x790/0x1090 mm/page_alloc.c:2950
qlink_free mm/kasan/quarantine.c:163 [inline]
qlist_free_all+0x47/0xf0 mm/kasan/quarantine.c:179
kasan_quarantine_reduce+0x1a0/0x1f0 mm/kasan/quarantine.c:286
__kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:350
kasan_slab_alloc include/linux/kasan.h:253 [inline]
slab_post_alloc_hook mm/slub.c:4584 [inline]
slab_alloc_node mm/slub.c:4917 [inline]
__do_kmalloc_node mm/slub.c:5333 [inline]
__kmalloc_noprof+0x2bf/0x820 mm/slub.c:5359
_kmalloc_noprof include/linux/slab.h:992 [inline]
tomoyo_realpath_from_path+0xb6/0x690 security/tomoyo/realpath.c:251
tomoyo_get_realpath security/tomoyo/file.c:151 [inline]
tomoyo_path_perm+0x276/0x460 security/tomoyo/file.c:827
security_inode_getattr+0x116/0x280 security/security.c:1895
vfs_getattr fs/stat.c:259 [inline]
vfs_statx_path fs/stat.c:299 [inline]
vfs_statx+0x11f/0x3f0 fs/stat.c:356
vfs_fstatat+0x77/0xe0 fs/stat.c:373
__do_sys_newfstatat+0x9d/0x120 fs/stat.c:538
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fbca3f11b0a
RSP: 002b:00007ffccceeafc8 EFLAGS: 00000246 ORIG_RAX: 0000000000000106
RAX: ffffffffffffffda RBX: 000055e6cea47410 RCX: 00007fbca3f11b0a
RDX: 00007ffccceeafd0 RSI: 000055e6cea352a8 RDI: 00000000ffffff9c
RBP: 000055e709a29668 R08: 00063478c1c69200 R09: 0000000000000001
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001
R13: 00007ffccceeafd0 R14: 0000000000000000 R15: 00063478c1c69200
rcu: rcu_preempt kthread starved for 281 jiffies! g252929 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:26200 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5510 [inline]
__schedule+0x125c/0x6730 kernel/sched/core.c:7234
__schedule_loop kernel/sched/core.c:7311 [inline]
schedule+0xdd/0x2c0 kernel/sched/core.c:7326
schedule_timeout+0x127/0x280 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x1a9/0x900 kernel/rcu/tree.c:2123
rcu_gp_kthread+0x179/0x230 kernel/rcu/tree.c:2325
kthread+0x370/0x450 kernel/kthread.c:436
ret_from_fork+0x72b/0xd50 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: 3223 Comm: kworker/R-bat_e Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026
Workqueue: bat_events batadv_tt_purge
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:179 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0x31/0x80 kernel/locking/spinlock.c:198
Code: f5 53 48 8b 74 24 10 48 89 fb 48 83 c7 18 e8 b6 ee 27 f6 48 89 df e8 3e 3e 28 f6 f7 c5 00 02 00 00 75 23 9c 58 f6 c4 02 75 37 01 00 00 00 e8 05 4e 17 f6 65 8b 05 4e 37 a6 08 85 c0 74 16 5b
RSP: 0018:ffffc90000007c68 EFLAGS: 00000246
RAX: 0000000000000002 RBX: ffff88802b310000 RCX: 0000000000000004
RDX: 0000000000000000 RSI: ffffffff8e1a5f23 RDI: ffffffff8c401680
RBP: 0000000000000246 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: ffff8881d59d1710
R13: ffff8881d59d1708 R14: ffff88802a77d4a3 R15: ffff88802a77d410
FS: 0000000000000000(0000) GS:ffff888123ddc000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffddf1f1ec0 CR3: 0000000039c2b000 CR4: 00000000003526f0
Call Trace:
spin_unlock_irqrestore include/linux/spinlock.h:408 [inline]
dummy_timer+0x1d91/0x36f0 drivers/usb/gadget/udc/dummy_hcd.c:2036
__run_hrtimer kernel/time/hrtimer.c:2032 [inline]
__hrtimer_run_queues+0x462/0x9c0 kernel/time/hrtimer.c:2096
hrtimer_run_softirq+0x17d/0x2c0 kernel/time/hrtimer.c:2113
handle_softirqs+0x1ea/0x9b0 kernel/softirq.c:622
do_softirq kernel/softirq.c:523 [inline]
do_softirq+0xac/0xe0 kernel/softirq.c:510
__local_bh_enable_ip+0xf8/0x120 kernel/softirq.c:450
spin_unlock_bh include/linux/spinlock.h:396 [inline]
batadv_tt_local_purge+0x21c/0x3d0 net/batman-adv/translation-table.c:1366
batadv_tt_purge+0x8b/0xbd0 net/batman-adv/translation-table.c:3565
process_one_work+0xa23/0x1940 kernel/workqueue.c:3322
process_scheduled_works kernel/workqueue.c:3405 [inline]
rescuer_thread+0x905/0x14a0 kernel/workqueue.c:3629
kthread+0x370/0x450 kernel/kthread.c:436
ret_from_fork+0x72b/0xd50 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245