rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P13085/1:b..l P1124/1:b..l rcu: (detected by 0, t=10502 jiffies, g=85161, q=884 ncpus=1) task:kworker/u8:9 state:R running task stack:23704 pid:1124 tgid:1124 ppid:2 task_flags:0x4208060 flags:0x00080000 Workqueue: events_unbound cfg80211_wiphy_work 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:write_comp_data+0xa/0x90 kernel/kcov.c:240 Code: e8 4b 91 70 00 e9 6d fd ff ff 66 0f 1f 44 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 65 8b 05 99 25 5a 12 49 89 f8 <49> 89 f1 49 89 d2 65 48 8b 3d 70 25 5a 12 a9 00 01 ff 00 74 1b f6 RSP: 0018:ffffc90005547878 EFLAGS: 00000296 RAX: 0000000080000000 RBX: ffff8880725e6888 RCX: ffffffff8b069544 RDX: 000000000000000c RSI: 000000000000000c RDI: 0000000000000004 RBP: 000000000000000b R08: 0000000000000004 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 000000000000000c R13: ffff8880725e3248 R14: 0000000000000004 R15: 000000000000000c ieee80211_mandatory_rates+0x194/0x220 net/wireless/util.c:62 ieee80211_update_sta_info.isra.0+0x3b1/0x1230 net/mac80211/ibss.c:959 ieee80211_rx_bss_info net/mac80211/ibss.c:1061 [inline] ieee80211_rx_mgmt_probe_beacon net/mac80211/ibss.c:1544 [inline] ieee80211_ibss_rx_queued_mgmt+0xdea/0x1c70 net/mac80211/ibss.c:1571 ieee80211_iface_process_skb net/mac80211/iface.c:1769 [inline] ieee80211_iface_work+0xa9a/0x1070 net/mac80211/iface.c:1823 cfg80211_wiphy_work+0x2b7/0x550 net/wireless/core.c:538 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.3.1387 state:R running task stack:26632 pid:13085 tgid:13084 ppid:5615 task_flags:0x40044c flags:0x00080003 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 3b 8d 7e 12 83 f8 07 0f 87 da 00 00 00 48 0f a3 05 c6 94 3c 0f 0f 82 ac 02 00 00 8b 35 8e c8 3c 0f 85 f6 0f 85 c7 00 00 00 <48> 8b 44 24 30 65 48 2b 05 dd 8c 7e 12 0f 85 ec 02 00 00 48 83 c4 RSP: 0018:ffffc9000411f3c0 EFLAGS: 00000206 RAX: 0000000000000046 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffffffff8e182264 RDI: ffffffff8c402680 RBP: ffffffff8ebe8200 R08: 0000000055f53773 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] __kmalloc_cache_noprof+0x265/0x6c0 mm/slub.c:5485 _kmalloc_noprof include/linux/slab.h:988 [inline] _kzalloc_noprof include/linux/slab.h:1309 [inline] kobject_uevent_env+0x263/0x18b0 lib/kobject_uevent.c:543 device_remove+0xcb/0x180 drivers/base/dd.c:616 __device_release_driver drivers/base/dd.c:1349 [inline] device_release_driver_internal+0x44e/0x620 drivers/base/dd.c:1372 driver_detach+0xd8/0x1b0 drivers/base/dd.c:1435 bus_remove_driver+0x13b/0x2e0 drivers/base/bus.c:832 driver_unregister+0x76/0xb0 drivers/base/driver.c:202 usb_gadget_unregister_driver+0x49/0x70 drivers/usb/gadget/udc/core.c:1784 raw_release+0x19b/0x260 drivers/usb/gadget/legacy/raw_gadget.c:463 __fput+0x3ff/0xb50 fs/file_table.c:512 task_work_run+0x150/0x240 kernel/task_work.c:233 exit_task_work include/linux/task_work.h:40 [inline] do_exit+0x951/0x2ae0 kernel/exit.c:1009 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+0x139/0x6f0 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: 0033:0x7f863cf5e84e RSP: 002b:00007f863b1f3ed8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e6 RAX: fffffffffffffdfc RBX: 00007f863b1f66c0 RCX: 00007f863cf5e84e RDX: 00007f863b1f3f30 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007f863b1f4fd0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000003 R13: 0000000800000000 R14: 0000000000000000 R15: 00007f863d05386a rcu: rcu_preempt kthread starved for 902 jiffies! g85161 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:27592 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: 3225 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 76 3f 27 f6 48 89 df e8 fe 8e 27 f6 f7 c5 00 02 00 00 75 23 9c 58 f6 c4 02 75 37 01 00 00 00 e8 05 9e 16 f6 65 8b 05 4e c7 a5 08 85 c0 74 16 5b RSP: 0018:ffffc90000007c68 EFLAGS: 00000246 RAX: 0000000000000006 RBX: ffff88802b27c000 RCX: 0000000000000004 RDX: 0000000000000000 RSI: ffffffff8e1a810c RDI: ffffffff8c402680 RBP: 0000000000000246 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000000 R12: ffff888189be2910 R13: ffff888189be2908 R14: ffff88802b4b84a3 R15: ffff88802b4b8410 FS: 0000000000000000(0000) GS:ffff888123dd8000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f6a2d9df451 CR3: 0000000034c01000 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