rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P6848/1:b..l P6880/1:b..l
rcu: (detected by 1, t=10503 jiffies, g=18433, q=482 ncpus=2)
task:udevd state:R running task stack:25992 pid:6880 ppid:5156 flags:0x00004002
Call Trace:
context_switch kernel/sched/core.c:5380 [inline]
__schedule+0x14d2/0x44d0 kernel/sched/core.c:6699
preempt_schedule_irq+0xb5/0x140 kernel/sched/core.c:7009
irqentry_exit+0x67/0x70 kernel/entry/common.c:438
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687
RIP: 0010:check_kcov_mode kernel/kcov.c:184 [inline]
RIP: 0010:write_comp_data kernel/kcov.c:245 [inline]
RIP: 0010:__sanitizer_cov_trace_const_cmp4+0x30/0x90 kernel/kcov.c:313
Code: 04 24 65 48 8b 15 40 21 7e 7e 65 8b 0d 41 21 7e 7e 81 e1 00 01 ff 00 74 11 81 f9 00 01 00 00 75 5b 83 ba 1c 16 00 00 00 74 52 <8b> 8a f8 15 00 00 83 f9 03 75 47 48 8b 8a 00 16 00 00 44 8b 8a fc
RSP: 0018:ffffc90003ad77b0 EFLAGS: 00000246
RAX: ffffffff81f03df9 RBX: 0000000000000051 RCX: 0000000000000000
RDX: ffff88802ab43c00 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90003ad7c48 R08: ffff88814b3fe4a0 R09: ffff88802c1a71a0
R10: ffff88814b3fe4a0 R11: ffff88802c1a71a0 R12: 1ffff9200075af89
R13: dffffc0000000000 R14: dffffc0000000000 R15: ffffc90003ad7c40
legitimize_links+0x49/0x430 fs/namei.c:727
try_to_unlazy+0x7b/0x5a0 fs/namei.c:780
may_lookup fs/namei.c:1729 [inline]
link_path_walk+0x2a3/0xe00 fs/namei.c:2279
path_openat+0x283/0x3190 fs/namei.c:3793
do_filp_open+0x1c5/0x3d0 fs/namei.c:3824
do_sys_openat2+0x12c/0x1c0 fs/open.c:1421
do_sys_open fs/open.c:1436 [inline]
__do_sys_openat fs/open.c:1452 [inline]
__se_sys_openat fs/open.c:1447 [inline]
__x64_sys_openat+0x139/0x160 fs/open.c:1447
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f2091ca7407
RSP: 002b:00007fff0835e530 EFLAGS: 00000202 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f209236c880 RCX: 00007f2091ca7407
RDX: 0000000000080000 RSI: 00007fff0835e660 RDI: ffffffffffffff9c
RBP: 00005573e68d8650 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 00005573e68d8740
R13: 00007fff0835e660 R14: 00005573e674b410 R15: 00007fff083602f0
task:kworker/u4:8 state:R running task stack:25496 pid:6848 ppid:2 flags:0x00004000
Workqueue: events_unbound cfg80211_wiphy_work
Call Trace:
context_switch kernel/sched/core.c:5380 [inline]
__schedule+0x14d2/0x44d0 kernel/sched/core.c:6699
preempt_schedule_irq+0xb5/0x140 kernel/sched/core.c:7009
irqentry_exit+0x67/0x70 kernel/entry/common.c:438
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687
RIP: 0010:ieee80211_update_sta_info net/mac80211/ibss.c:1006 [inline]
RIP: 0010:ieee80211_rx_bss_info net/mac80211/ibss.c:1122 [inline]
RIP: 0010:ieee80211_rx_mgmt_probe_beacon net/mac80211/ibss.c:1613 [inline]
RIP: 0010:ieee80211_ibss_rx_queued_mgmt+0x1008/0x2ac0 net/mac80211/ibss.c:1642
Code: 74 24 48 e8 4a fb fa ff 49 89 c6 48 8b 44 24 10 48 8d 58 38 48 89 d8 48 c1 e8 03 42 80 3c 38 00 74 08 48 89 df e8 f8 f2 f7 f7 <48> 83 3b 00 0f 84 51 01 00 00 4c 89 e7 48 8b 74 24 10 48 8b 5c 24
RSP: 0018:ffffc90003857820 EFLAGS: 00000246
RAX: 1ffff1100f56e507 RBX: ffff88807ab72838 RCX: 8fcb861c86164400
RDX: 0000000000000005 RSI: ffffffff8aaace60 RDI: ffffffff8afc6f80
RBP: ffffc90003857ae8 R08: ffffffff8e4a93ef R09: 1ffffffff1c9527d
R10: dffffc0000000000 R11: fffffbfff1c9527e R12: ffff88805b040c80
R13: ffff88805b041a88 R14: ffff88807a10c000 R15: dffffc0000000000
ieee80211_iface_process_skb net/mac80211/iface.c:1651 [inline]
ieee80211_iface_work+0x717/0xc70 net/mac80211/iface.c:1705
cfg80211_wiphy_work+0x225/0x260 net/wireless/core.c:437
process_one_work kernel/workqueue.c:2634 [inline]
process_scheduled_works+0xa45/0x15b0 kernel/workqueue.c:2711
worker_thread+0xa55/0xfc0 kernel/workqueue.c:2792
kthread+0x2fa/0x390 kernel/kthread.c:388
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
rcu: rcu_preempt kthread starved for 10566 jiffies! g18433 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:27752 pid:17 ppid:2 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5380 [inline]
__schedule+0x14d2/0x44d0 kernel/sched/core.c:6699
preempt_schedule_common+0x82/0xc0 kernel/sched/core.c:6866
preempt_schedule+0xab/0xc0 kernel/sched/core.c:6890
preempt_schedule_thunk+0x1a/0x30 arch/x86/entry/thunk_64.S:45
__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline]
_raw_spin_unlock_irqrestore+0xfa/0x110 kernel/locking/spinlock.c:194
__try_to_del_timer_sync+0x1d2/0x280 kernel/time/timer.c:1422
__timer_delete_sync+0x1ff/0x2c0 kernel/time/timer.c:1574
timer_delete_sync kernel/time/timer.c:1629 [inline]
del_timer_sync include/linux/timer.h:200 [inline]
schedule_timeout+0x16a/0x280 kernel/time/timer.c:2169
rcu_gp_fqs_loop+0x302/0x1560 kernel/rcu/tree.c:1667
rcu_gp_kthread+0x99/0x380 kernel/rcu/tree.c:1866
kthread+0x2fa/0x390 kernel/kthread.c:388
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 7135 Comm: syz.3.99 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:lookup_chain_cache kernel/locking/lockdep.c:3763 [inline]
RIP: 0010:lookup_chain_cache_add kernel/locking/lockdep.c:3782 [inline]
RIP: 0010:validate_chain kernel/locking/lockdep.c:3837 [inline]
RIP: 0010:__lock_acquire+0x1666/0x7c80 kernel/locking/lockdep.c:5137
Code: 7c 24 30 48 8b b4 24 a0 00 00 00 48 ba 00 00 00 00 00 fc ff df e9 5c ff ff ff 4c 8d 73 18 4c 89 f0 48 c1 e8 03 42 80 3c 00 00 <74> 12 4c 89 f7 e8 f0 e9 75 00 49 b8 00 00 00 00 00 fc ff df 49 8b
RSP: 0018:ffffc90000007900 EFLAGS: 00000046
RAX: 1ffffffff21b567f RBX: ffffffff90dab3e0 RCX: ffffffff81671100
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff90da9508
RBP: ffffc90000007b48 R08: dffffc0000000000 R09: 1ffffffff21b52a1
R10: dffffc0000000000 R11: fffffbfff21b52a2 R12: 3be9ba32c8301548
R13: ffff888028d61e00 R14: ffffffff90dab3f8 R15: ffff888028d62900
FS: 00007f9712ca06c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f2c25fb1d58 CR3: 000000002ae6d000 CR4: 00000000003506f0
Call Trace:
lock_acquire+0x197/0x410 kernel/locking/lockdep.c:5754
__raw_spin_lock_irq include/linux/spinlock_api_smp.h:119 [inline]
_raw_spin_lock_irq+0xa3/0xe0 kernel/locking/spinlock.c:170
__run_hrtimer kernel/time/hrtimer.c:1754 [inline]
__hrtimer_run_queues+0x5e3/0xc40 kernel/time/hrtimer.c:1814
hrtimer_interrupt+0x3c9/0x9c0 kernel/time/hrtimer.c:1876
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1077 [inline]
__sysvec_apic_timer_interrupt+0xfb/0x3b0 arch/x86/kernel/apic/apic.c:1094
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1088 [inline]
sysvec_apic_timer_interrupt+0x9f/0xc0 arch/x86/kernel/apic/apic.c:1088
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687
RIP: 0010:finish_task_switch+0x26a/0x920 kernel/sched/core.c:5254
Code: 0f 84 37 01 00 00 48 85 db 0f 85 56 01 00 00 0f 1f 44 00 00 4c 8b 75 d0 4c 89 e7 e8 c0 77 1c 09 e8 4b a4 2f 00 fb 4c 8b 65 c0 <49> 8d bc 24 f8 15 00 00 48 89 f8 48 c1 e8 03 42 0f b6 04 28 84 c0
RSP: 0018:ffffc900048cf798 EFLAGS: 00000282
RAX: eb45334f95040b00 RBX: 0000000000000000 RCX: eb45334f95040b00
RDX: dffffc0000000000 RSI: ffffffff8aaabce0 RDI: ffffffff8afc6f80
RBP: ffffc900048cf7f0 R08: ffffffff8e4a93ef R09: 1ffffffff1c9527d
R10: dffffc0000000000 R11: fffffbfff1c9527e R12: ffff888028d61e00
R13: dffffc0000000000 R14: ffff88802b585a00 R15: ffff8880b8e3cac8
context_switch kernel/sched/core.c:5383 [inline]
__schedule+0x14da/0x44d0 kernel/sched/core.c:6699
schedule+0xbd/0x170 kernel/sched/core.c:6773
uinput_read+0x778/0xaf0 drivers/input/misc/uinput.c:733
do_loop_readv_writev fs/read_write.c:-1 [inline]
do_iter_read+0x506/0xc80 fs/read_write.c:797
vfs_readv fs/read_write.c:915 [inline]
do_readv+0x235/0x3e0 fs/read_write.c:952
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f9711d8f749
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f9712ca0038 EFLAGS: 00000246 ORIG_RAX: 0000000000000013
RAX: ffffffffffffffda RBX: 00007f9711fe5fa0 RCX: 00007f9711d8f749
RDX: 0000000000000001 RSI: 0000200000000140 RDI: 0000000000000004
RBP: 00007f9711e13f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f9711fe6038 R14: 00007f9711fe5fa0 R15: 00007ffccc3e0718