rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P8125/1:b..l P5600/1:b..l
rcu: (detected by 0, t=10502 jiffies, g=39901, q=1128 ncpus=1)
task:kworker/0:3 state:R running task stack:22080 pid:5600 tgid:5600 ppid:2 task_flags:0x4208060 flags:0x00080000
Workqueue: usb_hub_wq hub_event
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+0x205/0xa10 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 99 9e 12 83 f8 07 0f 87 da 00 00 00 48 0f a3 05 86 ed 5b 0f 0f 82 ac 02 00 00 8b 35 4e 21 5c 0f 85 f6 0f 85 c7 00 00 00 <48> 8b 44 24 30 65 48 2b 05 9d 99 9e 12 0f 85 ec 02 00 00 48 83 c4
RSP: 0018:ffffc90003557318 EFLAGS: 00000206
RAX: 0000000000000046 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff8e381cb9 RDI: ffffffff8c602280
RBP: ffffffff8ede8300 R08: 00000000abe8db24 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]
class_rcu_constructor include/linux/rcupdate.h:1183 [inline]
unwind_next_frame+0xd1/0x2090 arch/x86/kernel/unwind_orc.c:495
arch_stack_walk+0x94/0xf0 arch/x86/kernel/stacktrace.c:25
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]
usb_alloc_urb+0x66/0xa0 drivers/usb/core/urb.c:75
usb_internal_control_msg drivers/usb/core/message.c:110 [inline]
usb_control_msg+0x1d3/0x4b0 drivers/usb/core/message.c:167
usb_get_descriptor+0xbb/0x1b0 drivers/usb/core/message.c:852
usb_get_device_descriptor+0x71/0xe0 drivers/usb/core/message.c:1125
hub_port_init+0x1768/0x37f0 drivers/usb/core/hub.c:5184
hub_port_connect drivers/usb/core/hub.c:5504 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5715 [inline]
port_event drivers/usb/core/hub.c:5879 [inline]
hub_event+0x2ead/0x4420 drivers/usb/core/hub.c:5961
process_one_work+0xa23/0x1940 kernel/workqueue.c:3322
process_scheduled_works kernel/workqueue.c:3405 [inline]
worker_thread+0x5ef/0xe50 kernel/workqueue.c:3486
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
task:syz.5.579 state:R running task stack:27144 pid:8125 tgid:8125 ppid:7489 task_flags:0x40044c flags:0x00080002
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+0x205/0xa10 kernel/entry/common.c:167
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674
RIP: 0010:lock_release+0x19e/0x310 kernel/locking/lockdep.c:5893
Code: ff 65 0f c1 05 e3 d9 9e 12 83 f8 01 0f 85 27 01 00 00 9c 58 f6 c4 02 0f 85 12 01 00 00 41 f7 c6 00 02 00 00 0f 85 c8 00 00 00 <48> 8b 44 24 10 65 48 2b 05 ed 92 9e 12 0f 85 4d 01 00 00 48 83 c4
RSP: 0018:ffffc9000459f2a0 EFLAGS: 00000206
RAX: 0000000000000046 RBX: ffffffff8ede8300 RCX: ffffc9000459f2ac
RDX: 0000000000000002 RSI: ffffffff8e381cb9 RDI: ffffffff8c602280
RBP: ffffffff81b876be R08: 0000000000000001 R09: 0000000000000007
R10: 0000000000000200 R11: 0000000000016f09 R12: ffff88803382cb00
R13: ffffc9000459f358 R14: 0000000000000202 R15: 0000000000000003
rcu_lock_release include/linux/rcupdate.h:310 [inline]
rcu_read_unlock include/linux/rcupdate.h:871 [inline]
class_rcu_destructor include/linux/rcupdate.h:1183 [inline]
unwind_next_frame+0x3c3/0x2090 arch/x86/kernel/unwind_orc.c:495
arch_stack_walk+0x94/0xf0 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122
kasan_save_stack+0x30/0x50 mm/kasan/common.c:57
kasan_save_track+0x14/0x30 mm/kasan/common.c:78
kasan_save_free_info+0x3b/0x70 mm/kasan/generic.c:584
poison_slab_object mm/kasan/common.c:253 [inline]
__kasan_slab_free+0x5f/0x80 mm/kasan/common.c:285
kasan_slab_free include/linux/kasan.h:235 [inline]
slab_free_hook mm/slub.c:2677 [inline]
slab_free mm/slub.c:6377 [inline]
kmem_cache_free+0x127/0x6b0 mm/slub.c:6504
anon_vma_chain_free mm/rmap.c:147 [inline]
unlink_anon_vmas+0x228/0x8e0 mm/rmap.c:514
free_pgtables+0x2e7/0xd80 mm/memory.c:414
exit_mmap+0x44c/0xa00 mm/mmap.c:1312
__mmput+0x12a/0x410 kernel/fork.c:1187
mmput+0x67/0x80 kernel/fork.c:1210
exit_mm kernel/exit.c:615 [inline]
do_exit+0x8b1/0x2ae0 kernel/exit.c:997
do_group_exit+0xd5/0x2a0 kernel/exit.c:1152
get_signal+0x1ec7/0x21e0 kernel/signal.c:3046
arch_do_signal_or_restart+0x91/0x7e0 arch/x86/kernel/signal.c:337
__exit_to_user_mode_loop kernel/entry/common.c:66 [inline]
exit_to_user_mode_loop+0x139/0x700 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:318 [inline]
do_syscall_64+0x666/0x870 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f8a5b39e0d9
RSP: 002b:00007ffc36746ac8 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: 0000000000000000 RBX: 00007ffc36746bb0 RCX: 00007f8a5b39e0d9
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 000000000003ccb7 R08: 0000000000000001 R09: 0000000000000000
R10: 0000001b2f420000 R11: 0000000000000246 R12: 00007ffc36746bf0
R13: 00007f8a5b625fac R14: 000000000003d2c7 R15: 00007f8a5b625fa0
rcu: rcu_preempt kthread starved for 4777 jiffies! g39901 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:28824 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: 3213 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 d6 e1 24 f6 48 89 df e8 5e 31 25 f6 f7 c5 00 02 00 00 75 23 9c 58 f6 c4 02 75 37 01 00 00 00 e8 05 3f 14 f6 65 8b 05 6e 76 c3 08 85 c0 74 16 5b
RSP: 0018:ffffc90000007c68 EFLAGS: 00000246
RAX: 0000000000000002 RBX: ffff88802bbd8000 RCX: 0000000000000004
RDX: 0000000000000000 RSI: ffffffff8e3a7c7f RDI: ffffffff8c602280
RBP: 0000000000000246 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: ffff8881b743fa10
R13: ffff8881b743fa08 R14: ffff88802be844a3 R15: ffff88802be84410
FS: 0000000000000000(0000) GS:ffff888123bd6000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f34be200218 CR3: 000000005d7d0000 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_global_purge net/batman-adv/translation-table.c:2301 [inline]
batadv_tt_purge+0x25d/0xbd0 net/batman-adv/translation-table.c:3566
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