rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P8953/1:b..l rcu: (detected by 1, t=10503 jiffies, g=26473, q=843 ncpus=2) task:syz-executor state:R running task stack:25800 pid:8953 tgid:8953 ppid:5799 task_flags:0x400000 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:orc_ip arch/x86/kernel/unwind_orc.c:80 [inline] RIP: 0010:__orc_find+0x68/0xf0 arch/x86/kernel/unwind_orc.c:102 Code: 8d 6b 04 49 89 df 49 39 ec 72 4e 4c 89 e2 48 29 ea 48 89 d6 48 c1 ea 3f 48 c1 fe 02 48 01 f2 48 d1 fa 48 8d 5c 95 00 48 89 da <48> c1 ea 03 0f b6 34 0a 48 89 da 83 e2 07 83 c2 03 40 38 f2 7c 05 RSP: 0018:ffffc900034f7448 EFLAGS: 00000203 RAX: ffffffff912dad6c RBX: ffffffff90a5d8b8 RCX: dffffc0000000000 RDX: ffffffff90a5d8b8 RSI: 0000000000000009 RDI: ffffffff90a5d87c RBP: ffffffff90a5d8a8 R08: ffffffff912dadea R09: 00000000ffffffff R10: 0000000000000002 R11: 0000000000011750 R12: ffffffff90a5d8cc R13: ffffffff821750bc R14: ffffffff90a5d87c R15: ffffffff90a5d8a4 orc_find arch/x86/kernel/unwind_orc.c:227 [inline] unwind_next_frame+0x2ec/0x20a0 arch/x86/kernel/unwind_orc.c:494 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:56 kasan_save_track+0x14/0x30 mm/kasan/common.c:77 unpoison_slab_object mm/kasan/common.c:339 [inline] __kasan_slab_alloc+0x89/0x90 mm/kasan/common.c:365 kasan_slab_alloc include/linux/kasan.h:252 [inline] slab_post_alloc_hook mm/slub.c:4948 [inline] slab_alloc_node mm/slub.c:5258 [inline] kmem_cache_alloc_node_noprof+0x298/0x800 mm/slub.c:5310 alloc_vmap_area+0x66f/0x2a50 mm/vmalloc.c:2060 __get_vm_area_node+0x1ca/0x330 mm/vmalloc.c:3219 __vmalloc_node_range_noprof+0x247/0x16b0 mm/vmalloc.c:4011 __vmalloc_node_noprof+0xad/0xf0 mm/vmalloc.c:4111 __vmalloc_area_node mm/vmalloc.c:3839 [inline] __vmalloc_node_range_noprof+0xee3/0x16b0 mm/vmalloc.c:4051 vmalloc_user_noprof+0x9e/0xe0 mm/vmalloc.c:4205 kcov_ioctl+0x4c/0x6e0 kernel/kcov.c:716 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:597 [inline] __se_sys_ioctl fs/ioctl.c:583 [inline] __x64_sys_ioctl+0x18e/0x210 fs/ioctl.c:583 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f8fb598f34b RSP: 002b:00007ffc72b93420 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000080000 RCX: 00007f8fb598f34b RDX: 0000000000080000 RSI: ffffffff80086301 RDI: 00000000000000d9 RBP: 00007f8fb5be6128 R08: 00000000000000d8 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000003 R14: 00007ffc72b93768 R15: 0000000000000000 rcu: rcu_preempt kthread starved for 10547 jiffies! g26473 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:28392 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: 1 UID: 0 PID: 0 Comm: swapper/1 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:lock_acquire+0x62/0x330 kernel/locking/lockdep.c:5872 Code: 96 17 12 83 f8 07 0f 87 a2 02 00 00 89 c0 48 0f a3 05 82 0f ee 0e 0f 82 74 02 00 00 8b 35 1a 40 ee 0e 85 f6 0f 85 8d 00 00 00 <48> 8b 44 24 30 65 48 2b 05 99 96 17 12 0f 85 ad 02 00 00 48 83 c4 RSP: 0018:ffffc90000a08af8 EFLAGS: 00000206 RAX: 0000000000000046 RBX: ffffffff8e3c9620 RCX: 00000000bf3fbf97 RDX: 0000000000000000 RSI: ffffffff8da9cb15 RDI: ffffffff8bf24880 RBP: 0000000000000002 R08: 00000000ac0d5af0 R09: 000000000ac0d5af R10: 0000000000000002 R11: ffff88801daa2ff0 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff888124a07000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b30203ff8 CR3: 0000000074d58000 CR4: 00000000003526f0 Call Trace: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] rcu_read_lock include/linux/rcupdate.h:867 [inline] link_sta_info_get_bss+0x6a/0x460 net/mac80211/sta_info.c:264 ieee80211_rx_for_interface+0x74/0x770 net/mac80211/rx.c:5197 __ieee80211_rx_handle_packet net/mac80211/rx.c:5400 [inline] ieee80211_rx_list+0x1141/0x2ed0 net/mac80211/rx.c:5539 ieee80211_rx_napi+0xdc/0x410 net/mac80211/rx.c:5562 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: f6 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 39 13 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:ffffc90000197de8 EFLAGS: 000002c6 RAX: 0000000001a99451 RBX: 0000000000000001 RCX: ffffffff8b7726d9 RDX: 0000000000000000 RSI: ffffffff8dac2bb5 RDI: ffffffff8bf24880 RBP: ffffed1003b54498 R08: 0000000000000001 R09: ffffed10170a673d R10: ffff8880b85339eb R11: ffff88801daa2ff0 R12: 0000000000000001 R13: ffff88801daa24c0 R14: ffffffff908808d0 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 start_secondary+0x21d/0x2d0 arch/x86/kernel/smpboot.c:312 common_startup_64+0x13e/0x148