rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P6372/1:b..l P6386/1:b..l
rcu: (detected by 0, t=10503 jiffies, g=10665, q=629 ncpus=2)
task:syz.0.117 state:R running task stack:19688 pid:6386 tgid:6385 ppid:5812 task_flags:0x40054c flags:0x00080001
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x1139/0x6150 kernel/sched/core.c:6863
preempt_schedule_notrace+0x62/0xe0 kernel/sched/core.c:7140
preempt_schedule_notrace_thunk+0x16/0x30 arch/x86/entry/thunk.S:13
rcu_is_watching+0x8e/0xc0 kernel/rcu/tree.c:752
rcu_read_unlock include/linux/rcupdate.h:895 [inline]
pte_unmap include/linux/pgtable.h:136 [inline]
zap_pte_range mm/memory.c:1884 [inline]
zap_pmd_range mm/memory.c:1946 [inline]
zap_pud_range mm/memory.c:1975 [inline]
zap_p4d_range mm/memory.c:1996 [inline]
unmap_page_range+0x1e0d/0x43c0 mm/memory.c:2017
unmap_single_vma+0x153/0x240 mm/memory.c:2059
unmap_vmas+0x218/0x470 mm/memory.c:2101
exit_mmap+0x1b0/0xb60 mm/mmap.c:1277
__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: 0033:0x7f68e738f749
RSP: 002b:00007f68e813e038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: 0000000000000014 RBX: 00007f68e75e5fa0 RCX: 00007f68e738f749
RDX: 00000000200048c4 RSI: 00002000000006c0 RDI: 0000000000000004
RBP: 00007f68e7413f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f68e75e6038 R14: 00007f68e75e5fa0 R15: 00007fff8d38b378
task:syz.3.115 state:R running task stack:26600 pid:6372 tgid:6372 ppid:5824 task_flags:0x40044c flags:0x00080002
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]
zap_pte_range mm/memory.c:1884 [inline]
zap_pmd_range mm/memory.c:1946 [inline]
zap_pud_range mm/memory.c:1975 [inline]
zap_p4d_range mm/memory.c:1996 [inline]
unmap_page_range+0x1047/0x43c0 mm/memory.c:2017
unmap_single_vma+0x153/0x240 mm/memory.c:2059
unmap_vmas+0x218/0x470 mm/memory.c:2101
exit_mmap+0x1b0/0xb60 mm/mmap.c:1277
__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: 0033:0x7fd6681865e7
RSP: 002b:00007fffc26f0108 EFLAGS: 00000202 ORIG_RAX: 0000000000000027
RAX: 000000000000005b RBX: 00007fffc26f0270 RCX: 00007fd6681865e7
RDX: 00007fffc26f0140 RSI: 00007fffc26f0270 RDI: 0000000000000021
RBP: 0000000000000000 R08: 00000000000000db R09: 0000000000000000
R10: 0000000000000011 R11: 0000000000000202 R12: 0000000000000003
R13: 00007fd6683e6270 R14: 0000000000001d87 R15: 0000000000000003
rcu: rcu_preempt kthread starved for 10550 jiffies! g10665 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:28376 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:
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:rcu_preempt_read_exit kernel/rcu/tree_plugin.h:398 [inline]
RIP: 0010:__rcu_read_unlock+0x86/0x5a0 kernel/rcu/tree_plugin.h:435
Code: 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 83 eb 01 0f b6 14 02 48 89 f8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 ee 01 00 00 <41> 89 9c 24 84 04 00 00 85 db 75 3b 48 8d bd 88 04 00 00 48 b8 00
RSP: 0018:ffffc900000075d0 EFLAGS: 00000246
RAX: 0000000000000007 RBX: 0000000000000002 RCX: ffffc900000075bc
RDX: 0000000000000000 RSI: ffffffff8daa9241 RDI: ffffffff8e097fc4
RBP: ffffffff8e097b40 R08: 0000000000000001 R09: 00000000f501fefe
R10: 0000000000000002 R11: 000000000000aada R12: ffffffff8e097b40
R13: ffffc90000007668 R14: ffffc90000007ef0 R15: ffffc9000000769c
FS: 0000000000000000(0000) GS:ffff8881248f1000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffd4ed44f88 CR3: 0000000062611000 CR4: 00000000003526f0
Call Trace:
rcu_read_unlock include/linux/rcupdate.h:899 [inline]
class_rcu_destructor include/linux/rcupdate.h:1195 [inline]
unwind_next_frame+0x3fe/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_save_track+0x14/0x30 mm/kasan/common.c:78
unpoison_slab_object mm/kasan/common.c:340 [inline]
__kasan_slab_alloc+0x89/0x90 mm/kasan/common.c:366
kasan_slab_alloc include/linux/kasan.h:253 [inline]
slab_post_alloc_hook mm/slub.c:4953 [inline]
slab_alloc_node mm/slub.c:5263 [inline]
kmem_cache_alloc_node_noprof+0x298/0x800 mm/slub.c:5315
__alloc_skb+0x156/0x410 net/core/skbuff.c:679
__netdev_alloc_skb+0x7a/0x920 net/core/skbuff.c:754
netdev_alloc_skb include/linux/skbuff.h:3484 [inline]
dev_alloc_skb include/linux/skbuff.h:3497 [inline]
__ieee80211_beacon_get+0xab1/0x1e40 net/mac80211/tx.c:5656
ieee80211_beacon_get_tim+0xa6/0x280 net/mac80211/tx.c:5778
ieee80211_beacon_get include/net/mac80211.h:5669 [inline]
mac80211_hwsim_beacon_tx+0x4dc/0xa40 drivers/net/wireless/virtual/mac80211_hwsim.c:2361
__iterate_interfaces+0x2e5/0x650 net/mac80211/util.c:761
ieee80211_iterate_active_interfaces_atomic+0x71/0x1b0 net/mac80211/util.c:797
mac80211_hwsim_beacon+0x105/0x1b0 drivers/net/wireless/virtual/mac80211_hwsim.c:2395
__run_hrtimer kernel/time/hrtimer.c:1777 [inline]
__hrtimer_run_queues+0x202/0xc40 kernel/time/hrtimer.c:1841
hrtimer_run_softirq+0x17d/0x350 kernel/time/hrtimer.c:1858
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: 26 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 99 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: 000000000046ae85 RBX: 0000000000000000 RCX: ffffffff8b78c6d9
RDX: 0000000000000000 RSI: ffffffff8dacf2d0 RDI: ffffffff8bf2b280
RBP: fffffbfff1c12f68 R08: 0000000000000001 R09: ffffed101708673d
R10: ffff8880b84339eb R11: ffffffff8e098670 R12: 0000000000000000
R13: ffffffff8e097b40 R14: ffffffff9088cad0 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