rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 1-....: (10494 ticks this GP) idle=c93c/1/0x4000000000000000 softirq=17408/17438 fqs=4184 rcu: hardirqs softirqs csw/system rcu: number: 2090808 107 0 rcu: cputime: 16412 36066 81 ==> 52480(ms) rcu: (t=10500 jiffies g=19645 q=1553 ncpus=2) CPU: 1 PID: 7271 Comm: syz.3.420 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 RIP: 0010:__sanitizer_cov_trace_cmp8+0x0/0x80 kernel/kcov.c:293 Code: c0 4c 89 01 48 c7 44 11 08 04 00 00 00 48 89 7c 11 10 48 89 74 11 18 48 89 44 11 20 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 0f 1e fa 48 8b 04 24 65 48 8b 0d 00 a0 7c 7e 65 8b 15 01 a0 7c RSP: 0018:ffffc900001f03d0 EFLAGS: 00000287 RAX: 0000000000000000 RBX: ffffffff8ea2aefc RCX: 000000000000000a RDX: dffffc0000000000 RSI: ffffffff81de6599 RDI: ffffffff81de65bd RBP: ffffffff8ea2aed4 R08: ffffc900001f0570 R09: 0000000000000021 R10: 0000000000000004 R11: 0000000000000100 R12: ffffffff8ea2aed4 R13: ffffffff81de65bd R14: ffffffff81de6599 R15: ffffffff8ea2aee8 FS: 00007f90854176c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055ea5d94a4b0 CR3: 000000002fa11000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: __orc_find arch/x86/kernel/unwind_orc.c:102 [inline] orc_find arch/x86/kernel/unwind_orc.c:227 [inline] unwind_next_frame+0x4b8/0x2970 arch/x86/kernel/unwind_orc.c:494 arch_stack_walk+0x144/0x190 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0xaa/0x100 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:46 [inline] kasan_set_track+0x4e/0x70 mm/kasan/common.c:53 __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:329 kasan_slab_alloc include/linux/kasan.h:188 [inline] slab_post_alloc_hook+0x6e/0x4b0 mm/slab.h:767 slab_alloc_node mm/slub.c:3495 [inline] kmem_cache_alloc_node+0x14c/0x320 mm/slub.c:3540 __alloc_skb+0x103/0x2c0 net/core/skbuff.c:643 __netdev_alloc_skb+0x10c/0x500 net/core/skbuff.c:717 netdev_alloc_skb include/linux/skbuff.h:3272 [inline] dev_alloc_skb include/linux/skbuff.h:3285 [inline] __ieee80211_beacon_get+0xe17/0x1600 net/mac80211/tx.c:5447 ieee80211_beacon_get_tim+0xbf/0x580 net/mac80211/tx.c:5569 ieee80211_beacon_get include/net/mac80211.h:5440 [inline] mac80211_hwsim_beacon_tx+0x3c7/0x780 drivers/net/wireless/virtual/mac80211_hwsim.c:2265 __iterate_interfaces+0x243/0x500 net/mac80211/util.c:766 ieee80211_iterate_active_interfaces_atomic+0xdb/0x180 net/mac80211/util.c:802 mac80211_hwsim_beacon+0xbb/0x1b0 drivers/net/wireless/virtual/mac80211_hwsim.c:2295 __run_hrtimer kernel/time/hrtimer.c:1750 [inline] __hrtimer_run_queues+0x52a/0xc40 kernel/time/hrtimer.c:1814 hrtimer_run_softirq+0x187/0x2b0 kernel/time/hrtimer.c:1831 handle_softirqs+0x280/0x820 kernel/softirq.c:578 __do_softirq kernel/softirq.c:612 [inline] invoke_softirq kernel/softirq.c:452 [inline] __irq_exit_rcu+0xd3/0x190 kernel/softirq.c:661 irq_exit_rcu+0x9/0x20 kernel/softirq.c:673 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1088 [inline] sysvec_apic_timer_interrupt+0xa4/0xc0 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/0x8f0 kernel/sched/core.c:5255 Code: 0f 84 33 01 00 00 48 85 db 0f 85 52 01 00 00 0f 1f 44 00 00 4c 8b 75 d0 4c 89 e7 e8 f0 a3 30 09 e8 8b 22 30 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:ffffc900194b6e38 EFLAGS: 00000282 RAX: 82a12d71e2746200 RBX: 0000000000000000 RCX: 82a12d71e2746200 RDX: dffffc0000000000 RSI: ffffffff8acac900 RDI: ffffffff8b1c81e0 RBP: ffffc900194b6e90 R08: ffffffff911bf52f R09: 1ffffffff2237ea5 R10: dffffc0000000000 R11: fffffbfff2237ea6 R12: ffff88807db21e00 R13: dffffc0000000000 R14: ffff8880186d3c00 R15: ffff8880b8f3cac8 context_switch kernel/sched/core.c:5384 [inline] __schedule+0x155b/0x45a0 kernel/sched/core.c:6700 preempt_schedule_common+0x82/0xc0 kernel/sched/core.c:6867 preempt_schedule+0xc0/0xd0 kernel/sched/core.c:6891 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+0x111/0x120 kernel/locking/spinlock.c:194 __debug_check_no_obj_freed lib/debugobjects.c:999 [inline] debug_check_no_obj_freed+0x51f/0x540 lib/debugobjects.c:1020 free_pages_prepare mm/page_alloc.c:1187 [inline] free_unref_page_prepare+0x1da/0x8c0 mm/page_alloc.c:2365 free_unref_page+0x32/0x2e0 mm/page_alloc.c:2458 __slab_free+0x35a/0x400 mm/slub.c:3736 qlink_free mm/kasan/quarantine.c:166 [inline] qlist_free_all+0x75/0xd0 mm/kasan/quarantine.c:185 kasan_quarantine_reduce+0x143/0x160 mm/kasan/quarantine.c:292 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:306 kasan_slab_alloc include/linux/kasan.h:188 [inline] slab_post_alloc_hook+0x6e/0x4b0 mm/slab.h:767 slab_alloc_node mm/slub.c:3495 [inline] __kmem_cache_alloc_node+0x13a/0x250 mm/slub.c:3534 __do_kmalloc_node mm/slab_common.c:1006 [inline] __kmalloc+0xa4/0x230 mm/slab_common.c:1020 kmalloc include/linux/slab.h:604 [inline] kzalloc include/linux/slab.h:721 [inline] tomoyo_encode2 security/tomoyo/realpath.c:45 [inline] tomoyo_encode+0x28b/0x540 security/tomoyo/realpath.c:80 tomoyo_realpath_from_path+0x592/0x5d0 security/tomoyo/realpath.c:283 tomoyo_get_realpath security/tomoyo/file.c:151 [inline] tomoyo_check_open_permission+0x224/0x460 security/tomoyo/file.c:771 security_file_open+0x62/0xa0 security/security.c:2854 do_dentry_open+0x380/0x1500 fs/open.c:916 do_open fs/namei.c:3640 [inline] path_openat+0x27f1/0x3230 fs/namei.c:3797 do_filp_open+0x1f5/0x430 fs/namei.c:3824 do_sys_openat2+0x134/0x1d0 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:46 [inline] do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f908459bf79 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:00007f9085417028 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007f9084815fa0 RCX: 00007f908459bf79 RDX: 0000000000000002 RSI: 0000200000000300 RDI: 000000000000000f RBP: 00007f90846327e0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f9084816038 R14: 00007f9084815fa0 R15: 00007ffcd6814218