rcu: INFO: rcu_preempt detected expedited stalls on CPUs/tasks: { 0-.... } 2670 jiffies s: 25497 root: 0x1/. rcu: blocking rcu_node structures (internal RCU debug): Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 8886 Comm: syz.1.1319 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 RIP: 0010:check_kcov_mode kernel/kcov.c:182 [inline] RIP: 0010:write_comp_data kernel/kcov.c:245 [inline] RIP: 0010:__sanitizer_cov_trace_const_cmp4+0x23/0x80 kernel/kcov.c:313 Code: 48 89 44 11 20 c3 90 48 8b 04 24 65 48 8b 15 c4 4a 80 7e 65 8b 0d c5 4a 80 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 RSP: 0018:ffffc90000007558 EFLAGS: 00000046 RAX: ffffffff81a550d1 RBX: 1ffff92000000eb0 RCX: 0000000000000100 RDX: ffff888027b61e00 RSI: 0000000000000102 RDI: 0000000000000000 RBP: ffffc90000007630 R08: ffff888027b61e07 R09: 1ffff11004f6c3c0 R10: dffffc0000000000 R11: ffffed1004f6c3c1 R12: 0000000000000102 R13: 0000000000000000 R14: ffff8880b8e35558 R15: ffff88801a2f0600 FS: 00007fd4f81006c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b2ff0bff8 CR3: 000000007d839000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: perf_swevent_event+0xf1/0x570 kernel/events/core.c:9609 perf_tp_event+0x36b/0xc10 kernel/events/core.c:10064 perf_trace_run_bpf_submit+0xf3/0x1c0 kernel/events/core.c:10032 perf_trace_preemptirq_template+0x268/0x320 include/trace/events/preemptirq.h:14 trace_irq_enable_rcuidle+0xd3/0x140 include/trace/events/preemptirq.h:40 trace_hardirqs_on+0x24/0x40 kernel/trace/trace_preemptirq.c:44 asm_sysvec_irq_work+0x16/0x20 arch/x86/include/asm/idtentry.h:728 RIP: 0010:rcu_read_unlock_special+0x7f/0x510 kernel/rcu/tree_plugin.h:685 Code: eb 03 48 b8 f1 f1 f1 f1 f8 f2 f2 f2 4a 89 04 2b 42 c7 44 2b 08 f8 f3 f3 f3 65 44 8b 35 e2 82 95 7e 41 f7 c6 00 00 f0 00 74 40 <48> c7 44 24 40 0e 36 e0 45 4a c7 04 2b 00 00 00 00 42 c7 44 2b 08 RSP: 0018:ffffc90000007ae0 EFLAGS: 00000206 RAX: 5af6b98713818200 RBX: 1ffff92000000f64 RCX: 5af6b98713818200 RDX: dffffc0000000000 RSI: ffffffff8a8c17a0 RDI: ffffffff8adee1a0 RBP: ffffc90000007bd0 R08: ffff8880b8e3580b R09: 1ffff110171c6b01 R10: dffffc0000000000 R11: ffffed10171c6b02 R12: 0000000000000246 R13: dffffc0000000000 R14: ffff8880b8e3bb00 R15: 0000000000000001 __rcu_read_unlock+0x78/0xd0 kernel/rcu/tree_plugin.h:426 rcu_read_unlock include/linux/rcupdate.h:823 [inline] ieee80211_iterate_active_interfaces_atomic+0x156/0x170 net/mac80211/util.c:826 mac80211_hwsim_beacon+0xb7/0x1b0 drivers/net/wireless/mac80211_hwsim.c:2147 __run_hrtimer kernel/time/hrtimer.c:1751 [inline] __hrtimer_run_queues+0x522/0xc90 kernel/time/hrtimer.c:1815 hrtimer_run_softirq+0x173/0x290 kernel/time/hrtimer.c:1832 handle_softirqs+0x291/0x910 kernel/softirq.c:596 __do_softirq kernel/softirq.c:630 [inline] invoke_softirq kernel/softirq.c:470 [inline] __irq_exit_rcu+0x13b/0x230 kernel/softirq.c:679 irq_exit_rcu+0x5/0x20 kernel/softirq.c:691 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1118 [inline] sysvec_apic_timer_interrupt+0xa0/0xc0 arch/x86/kernel/apic/apic.c:1118 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691 RIP: 0010:finish_task_switch+0x267/0x8e0 kernel/sched/core.c:5124 Code: d1 08 85 c0 0f 84 38 01 00 00 48 85 db 0f 85 57 01 00 00 0f 1f 44 00 00 4c 89 e7 e8 33 6f db 08 e8 ae 05 2f 00 fb 4c 8b 65 b8 <49> 8d bc 24 f8 15 00 00 48 89 f8 48 c1 e8 03 42 0f b6 04 30 84 c0 RSP: 0018:ffffc9000d4bf520 EFLAGS: 00000282 RAX: 5af6b98713818200 RBX: 0000000000000000 RCX: 5af6b98713818200 RDX: dffffc0000000000 RSI: ffffffff8a8c17a0 RDI: ffffffff8adee1a0 RBP: ffffc9000d4bf570 R08: ffff8880b8e3580b R09: 1ffff110171c6b01 R10: dffffc0000000000 R11: ffffed10171c6b02 R12: ffff888027b61e00 R13: 1ffff110171c76fa R14: dffffc0000000000 R15: ffff8880b8e3b7d0 context_switch kernel/sched/core.c:5248 [inline] __schedule+0x1087/0x4030 kernel/sched/core.c:6562 preempt_schedule_common+0x82/0xd0 kernel/sched/core.c:6731 preempt_schedule+0xbc/0xd0 kernel/sched/core.c:6755 preempt_schedule_thunk+0x16/0x18 arch/x86/entry/thunk_64.S:34 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline] _raw_spin_unlock_irqrestore+0x10d/0x120 kernel/locking/spinlock.c:194 __debug_check_no_obj_freed lib/debugobjects.c:988 [inline] debug_check_no_obj_freed+0x471/0x520 lib/debugobjects.c:1009 free_pages_prepare mm/page_alloc.c:1493 [inline] free_pcp_prepare mm/page_alloc.c:1537 [inline] free_unref_page_prepare+0x2c3/0x9e0 mm/page_alloc.c:3414 free_unref_page+0x2e/0x3f0 mm/page_alloc.c:3509 qlink_free mm/kasan/quarantine.c:168 [inline] qlist_free_all+0x76/0xe0 mm/kasan/quarantine.c:187 kasan_quarantine_reduce+0x144/0x160 mm/kasan/quarantine.c:294 __kasan_slab_alloc+0x1e/0x80 mm/kasan/common.c:306 kasan_slab_alloc include/linux/kasan.h:201 [inline] slab_post_alloc_hook+0x4b/0x490 mm/slab.h:737 slab_alloc_node mm/slub.c:3359 [inline] __kmem_cache_alloc_node+0x19d/0x270 mm/slub.c:3398 __do_kmalloc_node mm/slab_common.c:935 [inline] __kmalloc+0xa3/0x240 mm/slab_common.c:949 kmalloc include/linux/slab.h:568 [inline] tomoyo_realpath_from_path+0xe2/0x5c0 security/tomoyo/realpath.c:251 tomoyo_get_realpath security/tomoyo/file.c:151 [inline] tomoyo_path_number_perm+0x22f/0x650 security/tomoyo/file.c:723 security_file_ioctl+0x6c/0xa0 security/security.c:1569 __do_sys_ioctl fs/ioctl.c:864 [inline] __se_sys_ioctl+0x48/0x170 fs/ioctl.c:856 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7fd4f719ce59 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fd4f8100028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007fd4f7415fa0 RCX: 00007fd4f719ce59 RDX: 0000200000000040 RSI: 00000000401054d5 RDI: 000000000000000e RBP: 00007fd4f7232e6f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fd4f7416038 R14: 00007fd4f7415fa0 R15: 00007fff4d3d3b48