rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P6408/1:b..l
rcu: (detected by 1, t=10502 jiffies, g=19101, q=674 ncpus=2)
task:syz.4.21 state:R running task stack:26080 pid:6408 tgid:6406 ppid:6133 task_flags:0x40044c flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x14bc/0x5000 kernel/sched/core.c:6863
preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7190
irqentry_exit+0x5d8/0x660 kernel/entry/common.c:216
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:lock_acquire+0x16c/0x340 kernel/locking/lockdep.c:5872
Code: 00 00 00 00 9c 8f 44 24 30 f7 44 24 30 00 02 00 00 0f 85 cd 00 00 00 f7 44 24 08 00 02 00 00 74 01 fb 65 48 8b 05 d4 38 e0 10 <48> 3b 44 24 58 0f 85 e5 00 00 00 48 83 c4 60 5b 41 5c 41 5d 41 5e
RSP: 0018:ffffc900045ef398 EFLAGS: 00000206
RAX: b48d198e6fb00000 RBX: 0000000000000000 RCX: b48d198e6fb00000
RDX: 00000000951bad47 RSI: ffffffff8d979277 RDI: ffffffff8bc08360
RBP: ffffffff81743f85 R08: ffffffff81743f85 R09: ffffffff8df41a20
R10: ffffc900045ef558 R11: ffffffff81ada120 R12: 0000000000000002
R13: ffffffff8df41a20 R14: 0000000000000000 R15: 0000000000000246
rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
rcu_read_lock include/linux/rcupdate.h:867 [inline]
class_rcu_constructor include/linux/rcupdate.h:1195 [inline]
unwind_next_frame+0xc2/0x23d0 arch/x86/kernel/unwind_orc.c:495
arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
save_stack+0xf5/0x1f0 mm/page_owner.c:165
__reset_page_owner+0x71/0x1f0 mm/page_owner.c:320
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1395 [inline]
__free_frozen_pages+0xbc8/0xd30 mm/page_alloc.c:2943
__slab_free+0x21b/0x2a0 mm/slub.c:6004
qlink_free mm/kasan/quarantine.c:163 [inline]
qlist_free_all+0x97/0x100 mm/kasan/quarantine.c:179
kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286
__kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:349
kasan_slab_alloc include/linux/kasan.h:252 [inline]
slab_post_alloc_hook mm/slub.c:4953 [inline]
slab_alloc_node mm/slub.c:5263 [inline]
kmem_cache_alloc_noprof+0x37d/0x710 mm/slub.c:5270
taskstats_tgid_alloc kernel/taskstats.c:576 [inline]
taskstats_exit+0x14a/0xa30 kernel/taskstats.c:615
do_exit+0x638/0x2310 kernel/exit.c:941
do_group_exit+0x21c/0x2d0 kernel/exit.c:1112
get_signal+0x1285/0x1340 kernel/signal.c:3034
arch_do_signal_or_restart+0x9a/0x7a0 arch/x86/kernel/signal.c:337
__exit_to_user_mode_loop kernel/entry/common.c:41 [inline]
exit_to_user_mode_loop+0x87/0x4f0 kernel/entry/common.c:75
__exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline]
syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline]
syscall_exit_to_user_mode_work include/linux/entry-common.h:159 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:194 [inline]
ret_from_fork+0x616/0xb30 arch/x86/kernel/process.c:167
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
rcu: rcu_preempt kthread starved for 3082 jiffies! g19101 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1
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:26968 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x14bc/0x5000 kernel/sched/core.c:6863
__schedule_loop kernel/sched/core.c:6945 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6960
schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x301/0x1540 kernel/rcu/tree.c:2083
rcu_gp_kthread+0x99/0x390 kernel/rcu/tree.c:2285
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x599/0xb30 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
rcu: Stack dump where RCU GP kthread last ran:
CPU: 1 UID: 0 PID: 36 Comm: kworker/u8:2 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Workqueue: events_unbound cfg80211_wiphy_work
RIP: 0010:finish_task_switch+0x242/0x940 kernel/sched/core.c:5114
Code: 0f 84 c2 01 00 00 48 85 db 0f 85 e9 01 00 00 0f 1f 44 00 00 4c 8b 75 d0 4c 89 e7 e8 28 4a cc 09 e8 83 75 37 00 fb 4c 8b 65 c0 <49> 8d bc 24 48 16 00 00 48 89 f8 48 c1 e8 03 42 0f b6 04 28 84 c0
RSP: 0018:ffffc90000ac6598 EFLAGS: 00000282
RAX: d71d888b5e913800 RBX: 0000000000000000 RCX: d71d888b5e913800
RDX: 0000000000000006 RSI: ffffffff8d7925e3 RDI: ffffffff8bc08360
RBP: ffffc90000ac65f0 R08: ffffffff8f822077 R09: 1ffffffff1f0440e
R10: dffffc0000000000 R11: fffffbfff1f0440f R12: ffff8881412d1e80
R13: dffffc0000000000 R14: ffff88802aef9e80 R15: ffff8880b873b498
FS: 0000000000000000(0000) GS:ffff888125f35000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000c000525d40 CR3: 0000000077e24000 CR4: 00000000003526f0
Call Trace:
context_switch kernel/sched/core.c:5259 [inline]
__schedule+0x14c4/0x5000 kernel/sched/core.c:6863
preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7190
irqentry_exit+0x5d8/0x660 kernel/entry/common.c:216
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:unwind_next_frame+0x4a5/0x23d0 arch/x86/kernel/unwind_orc.c:520
Code: e0 48 c1 e8 03 0f b6 04 28 84 c0 0f 85 6d 18 00 00 4c 89 e8 48 c1 e8 03 0f b6 04 28 84 c0 0f 85 80 18 00 00 41 0f b6 44 24 01 <83> e0 07 0f 84 6d 15 00 00 83 f8 01 4c 8b 7c 24 50 48 bd 00 00 00
RSP: 0018:ffffc90000ac69d8 EFLAGS: 00000246
RAX: 0000000000000002 RBX: ffffffff9001f49c RCX: ffffffff9001f4a0
RDX: ffffffff90b15cd0 RSI: ffffffff90b15cd0 RDI: ffffffff8bc08300
RBP: dffffc0000000000 R08: 0000000000000001 R09: ffffffff8df41a20
R10: ffffc90000ac6af8 R11: ffffffff81ada120 R12: ffffffff90b15cd4
R13: ffffffff90b15cd5 R14: ffffc90000ac6aa8 R15: ffffffff9001f49c
arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
kasan_save_stack mm/kasan/common.c:56 [inline]
kasan_save_track+0x3e/0x80 mm/kasan/common.c:77
poison_kmalloc_redzone mm/kasan/common.c:397 [inline]
__kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:414
kasan_kmalloc include/linux/kasan.h:262 [inline]
__do_kmalloc_node mm/slub.c:5657 [inline]
__kmalloc_noprof+0x41d/0x800 mm/slub.c:5669
kmalloc_noprof include/linux/slab.h:961 [inline]
kzalloc_noprof include/linux/slab.h:1094 [inline]
cfg80211_inform_single_bss_data+0x91e/0x1ad0 net/wireless/scan.c:2345
cfg80211_inform_bss_data+0x203/0x3b40 net/wireless/scan.c:3228
cfg80211_inform_bss_frame_data+0x3c7/0x710 net/wireless/scan.c:3319
ieee80211_bss_info_update+0x749/0x9e0 net/mac80211/scan.c:230
ieee80211_rx_bss_info net/mac80211/ibss.c:1094 [inline]
ieee80211_rx_mgmt_probe_beacon net/mac80211/ibss.c:1575 [inline]
ieee80211_ibss_rx_queued_mgmt+0xa5d/0x2af0 net/mac80211/ibss.c:1602
ieee80211_iface_process_skb net/mac80211/iface.c:1736 [inline]
ieee80211_iface_work+0x85f/0x12d0 net/mac80211/iface.c:1790
cfg80211_wiphy_work+0x2ab/0x450 net/wireless/core.c:438
process_one_work kernel/workqueue.c:3257 [inline]
process_scheduled_works+0xad1/0x1770 kernel/workqueue.c:3340
worker_thread+0x8a0/0xda0 kernel/workqueue.c:3421
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x599/0xb30 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246