rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P21220/1:b..l P21200/1:b..l
rcu: (detected by 1, t=10502 jiffies, g=101481, q=563 ncpus=2)
task:syz.2.3859 state:R running task stack:26480 pid:21200 tgid:21196 ppid:20507 task_flags:0x40044c flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x1139/0x6150 kernel/sched/core.c:6863
preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7190
irqentry_exit+0x1d8/0x8c0 kernel/entry/common.c:216
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:lock_acquire+0x62/0x330 kernel/locking/lockdep.c:5872
Code: b3 18 12 83 f8 07 0f 87 a2 02 00 00 89 c0 48 0f a3 05 52 b1 ee 0e 0f 82 74 02 00 00 8b 35 ea e1 ee 0e 85 f6 0f 85 8d 00 00 00 <48> 8b 44 24 30 65 48 2b 05 69 b3 18 12 0f 85 ad 02 00 00 48 83 c4
RSP: 0018:ffffc900046df300 EFLAGS: 00000206
RAX: 0000000000000046 RBX: ffffffff8e3c96a0 RCX: 00000000ace16c1f
RDX: 0000000000000000 RSI: ffffffff8daa8a1d RDI: ffffffff8bf2b400
RBP: 0000000000000002 R08: 0000000027c185dd R09: 00000000d27c185d
R10: 0000000000000002 R11: ffff888026698b30 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
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+0xd1/0x20b0 arch/x86/kernel/unwind_orc.c:495
arch_stack_walk+0x94/0x100 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122
kasan_save_stack+0x33/0x60 mm/kasan/common.c:57
kasan_record_aux_stack+0xa7/0xc0 mm/kasan/generic.c:556
slab_free_hook mm/slub.c:2501 [inline]
slab_free mm/slub.c:6670 [inline]
kmem_cache_free+0x15e/0x770 mm/slub.c:6781
anon_vma_free mm/rmap.c:136 [inline]
__put_anon_vma+0x114/0x3a0 mm/rmap.c:2780
put_anon_vma include/linux/rmap.h:117 [inline]
unlink_anon_vmas+0x58a/0x820 mm/rmap.c:443
free_pgtables+0x212/0xc10 mm/memory.c:414
exit_mmap+0x3f1/0xb60 mm/mmap.c:1288
__mmput+0x12a/0x410 kernel/fork.c:1173
mmput+0x62/0x70 kernel/fork.c:1196
exit_mm kernel/exit.c:581 [inline]
do_exit+0x7d7/0x2bd0 kernel/exit.c:959
do_group_exit+0xd3/0x2a0 kernel/exit.c:1112
get_signal+0x2671/0x26d0 kernel/signal.c:3034
arch_do_signal_or_restart+0x8f/0x7e0 arch/x86/kernel/signal.c:337
__exit_to_user_mode_loop kernel/entry/common.c:41 [inline]
exit_to_user_mode_loop+0x8c/0x540 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]
do_syscall_64+0x4ee/0xf80 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f7d83d8f749
RSP: 002b:00007f7d84c8a0e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 00007f7d83fe6098 RCX: 00007f7d83d8f749
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f7d83fe6098
RBP: 00007f7d83fe6090 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f7d83fe6128 R14: 00007fff3addb260 R15: 00007fff3addb348
task:dhcpcd-run-hook state:R running task stack:28264 pid:21220 tgid:21220 ppid:21182 task_flags:0x400040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x1139/0x6150 kernel/sched/core.c:6863
preempt_schedule_common+0x44/0xc0 kernel/sched/core.c:7047
preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12
__raw_spin_unlock include/linux/spinlock_api_smp.h:143 [inline]
_raw_spin_unlock+0x3e/0x50 kernel/locking/spinlock.c:186
spin_unlock include/linux/spinlock.h:391 [inline]
wp_page_copy mm/memory.c:3820 [inline]
do_wp_page+0x1818/0x5010 mm/memory.c:4180
handle_pte_fault mm/memory.c:6289 [inline]
__handle_mm_fault+0x1bd2/0x2bb0 mm/memory.c:6411
handle_mm_fault+0x3fe/0xad0 mm/memory.c:6580
do_user_addr_fault+0x60c/0x1370 arch/x86/mm/fault.c:1336
handle_page_fault arch/x86/mm/fault.c:1476 [inline]
exc_page_fault+0x64/0xc0 arch/x86/mm/fault.c:1532
asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618
RIP: 0033:0x7f67ce791458
RSP: 002b:00007ffea0d3ce50 EFLAGS: 00010206
RAX: 0000000000000003 RBX: 000056465571e170 RCX: 0000000000000003
RDX: 0000000000000000 RSI: 000056465571e170 RDI: 000056465571fd00
RBP: 000056465570f5e0 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000001 R15: 0000000000000003
rcu: rcu_preempt kthread starved for 10557 jiffies! g101481 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:28064 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x1139/0x6150 kernel/sched/core.c:6863
__schedule_loop kernel/sched/core.c:6945 [inline]
schedule+0xe7/0x3a0 kernel/sched/core.c:6960
schedule_timeout+0x123/0x290 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x1ea/0xaf0 kernel/rcu/tree.c:2083
rcu_gp_kthread+0x26d/0x380 kernel/rcu/tree.c:2285
kthread+0x3c5/0x780 kernel/kthread.c:463
ret_from_fork+0x983/0xb10 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:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:__sanitizer_cov_trace_switch+0x40/0x90 kernel/kcov.c:351
Code: 48 83 f8 20 74 6b 77 48 48 83 f8 08 74 5b 48 83 f8 10 75 2f 41 bd 03 00 00 00 4c 8b 75 00 31 db 4d 85 f6 74 1e 48 8b 74 dd 10 <48> 8b 4c 24 28 4c 89 e2 4c 89 ef 48 83 c3 01 e8 8c fd ff ff 49 39
RSP: 0018:ffffc90000007730 EFLAGS: 00000206
RAX: 0000000000000000 RBX: 0000000000000002 RCX: ffffffff8af30375
RDX: ffffffff8e097b40 RSI: 0000000000000040 RDI: 0000000000000003
RBP: ffffffff8ce85c80 R08: 0000000000000003 R09: 0000000000000030
R10: 0000000000000080 R11: ffffffff8e098670 R12: 0000000000000080
R13: 0000000000000003 R14: 0000000000000008 R15: 0000000000000080
FS: 0000000000000000(0000) GS:ffff8881248f4000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c3577ca CR3: 000000000e184000 CR4: 00000000003526f0
Call Trace:
ieee80211_rx_h_mgmt net/mac80211/rx.c:4120 [inline]
ieee80211_rx_handlers+0x9df5/0xa100 net/mac80211/rx.c:4232
ieee80211_invoke_rx_handlers net/mac80211/rx.c:4262 [inline]
ieee80211_prepare_and_rx_handle+0x2bb6/0x7830 net/mac80211/rx.c:5132
ieee80211_rx_for_interface+0x110/0x770 net/mac80211/rx.c:5233
__ieee80211_rx_handle_packet net/mac80211/rx.c:5405 [inline]
ieee80211_rx_list+0x1141/0x2ed0 net/mac80211/rx.c:5544
ieee80211_rx_napi+0xdc/0x410 net/mac80211/rx.c:5567
ieee80211_rx include/net/mac80211.h:5216 [inline]
ieee80211_handle_queued_frames+0xcf/0x130 net/mac80211/main.c:452
tasklet_action_common+0x254/0x3f0 kernel/softirq.c:925
handle_softirqs+0x219/0x950 kernel/softirq.c:622
__do_softirq kernel/softirq.c:656 [inline]
invoke_softirq kernel/softirq.c:496 [inline]
__irq_exit_rcu+0x109/0x170 kernel/softirq.c:723
irq_exit_rcu+0x9/0x30 kernel/softirq.c:739
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline]
sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1056
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:82
Code: 86 5f 02 c3 cc cc cc cc 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d 13 f9 11 00 fb f4 cc 35 03 00 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90
RSP: 0018:ffffffff8e007df8 EFLAGS: 000002c6
RAX: 0000000005020ac9 RBX: 0000000000000000 RCX: ffffffff8b7866d9
RDX: 0000000000000000 RSI: ffffffff8daceab2 RDI: ffffffff8bf2b400
RBP: fffffbfff1c12f68 R08: 0000000000000001 R09: ffffed101708673d
R10: ffff8880b84339eb R11: ffffffff8e098670 R12: 0000000000000000
R13: ffffffff8e097b40 R14: ffffffff9088bdd0 R15: 0000000000000000
arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline]
default_idle+0x13/0x20 arch/x86/kernel/process.c:767
default_idle_call+0x6c/0xb0 kernel/sched/idle.c:122
cpuidle_idle_call kernel/sched/idle.c:191 [inline]
do_idle+0x38d/0x510 kernel/sched/idle.c:332
cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:430
rest_init+0x16b/0x2b0 init/main.c:757
start_kernel+0x3ef/0x4d0 init/main.c:1206
x86_64_start_reservations+0x18/0x30 arch/x86/kernel/head64.c:310
x86_64_start_kernel+0x130/0x190 arch/x86/kernel/head64.c:291
common_startup_64+0x13e/0x148