rcu: INFO: rcu_preempt detected expedited stalls on CPUs/tasks: { 0-.... } 2680 jiffies s: 90529 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: 15187 Comm: syz.1.2851 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/16/2026 RIP: 0010:rcu_dynticks_curr_cpu_in_eqs include/linux/context_tracking.h:122 [inline] RIP: 0010:rcu_is_watching+0x11/0xa0 kernel/rcu/tree.c:721 Code: f6 e8 d3 d8 d1 02 e9 44 ff ff ff 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 41 57 41 56 53 65 ff 05 6c 45 96 7e e8 1f 73 c6 08 <89> c3 83 f8 08 73 60 49 bf 00 00 00 00 00 fc ff df 4c 8d 34 dd 80 RSP: 0018:ffffc90000007090 EFLAGS: 00000082 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 5a4cc9599b467200 RDX: ffff888054730000 RSI: ffffffff8adf6880 RDI: ffffffff8adf6840 RBP: ffffc900000071f0 R08: ffffc90000007177 R09: ffffc90000007160 R10: dffffc0000000000 R11: fffff52000000e2f R12: 1ffff92000000e28 R13: ffffc90000007240 R14: 0000000000000008 R15: ffff888073a76600 FS: 00007f669f5f66c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fde576f1ff8 CR3: 0000000077b8f000 CR4: 00000000003506f0 DR0: 0000200000000300 DR1: 0000200000000300 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: rcu_read_lock_held_common kernel/rcu/update.c:108 [inline] rcu_read_lock_held+0x11/0x40 kernel/rcu/update.c:309 __perf_output_begin kernel/events/ring_buffer.c:170 [inline] perf_output_begin_forward+0x1d1/0xa70 kernel/events/ring_buffer.c:272 __perf_event_output kernel/events/core.c:7742 [inline] perf_event_output_forward+0x1ad/0x2f0 kernel/events/core.c:7760 __perf_event_overflow+0x457/0x630 kernel/events/core.c:9506 perf_swevent_overflow+0x19b/0x230 kernel/events/core.c:9589 perf_swevent_event+0x458/0x570 kernel/events/core.c:-1 perf_tp_event+0x36b/0xc10 kernel/events/core.c:10074 perf_trace_run_bpf_submit+0xf3/0x1c0 kernel/events/core.c:10042 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 32 7b 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:ffffc90000007980 EFLAGS: 00000206 RAX: 5a4cc9599b467200 RBX: 1ffff92000000f38 RCX: 5a4cc9599b467200 RDX: dffffc0000000000 RSI: ffffffff8a8c18a0 RDI: ffffffff8adf68a0 RBP: ffffc90000007a80 R08: ffffffff90b0f32f R09: 1ffffffff2161e65 R10: dffffc0000000000 R11: fffffbfff2161e66 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] hsr_announce+0x2ca/0x340 net/hsr/hsr_device.c:427 call_timer_fn+0x1ac/0x670 kernel/time/timer.c:1701 expire_timers kernel/time/timer.c:1752 [inline] __run_timers+0x56c/0x810 kernel/time/timer.c:2023 run_timer_softirq+0x63/0xf0 kernel/time/timer.c:2036 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:put_cpu_partial+0x1b0/0x250 mm/slub.c:2666 Code: 3b 44 24 18 0f 85 b4 00 00 00 48 83 c4 20 5b 41 5c 41 5d 41 5e 41 5f 5d c3 e8 dc 8a 5f 08 f7 c5 00 02 00 00 74 c0 fb 4d 85 e4 <75> bf eb c8 e8 67 1d 40 02 85 c0 0f 84 e9 fe ff ff 83 3d 80 eb 4d RSP: 0018:ffffc900058a76a8 EFLAGS: 00000246 RAX: 5a4cc9599b467200 RBX: ffff8880174c5000 RCX: 5a4cc9599b467200 RDX: dffffc0000000000 RSI: ffffffff8a8c18a0 RDI: ffffffff8adf68a0 RBP: 0000000000000282 R08: ffffffff90b0f35f R09: 1ffffffff2161e6b R10: dffffc0000000000 R11: fffffbfff2161e6c R12: 0000000000000000 R13: 0000000000000000 R14: ffff888054730000 R15: ffff8880b8e3f970 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 kmalloc_trace+0x26/0xe0 mm/slab_common.c:1026 kmalloc include/linux/slab.h:563 [inline] kzalloc include/linux/slab.h:699 [inline] kernfs_fop_open+0x3ce/0xc60 fs/kernfs/file.c:690 do_dentry_open+0x7dd/0x10b0 fs/open.c:882 do_open fs/namei.c:3677 [inline] path_openat+0x2674/0x2f10 fs/namei.c:3834 do_filp_open+0x1ee/0x420 fs/namei.c:3861 do_sys_openat2+0x14b/0x4f0 fs/open.c:1320 do_sys_open fs/open.c:1336 [inline] __do_sys_openat fs/open.c:1352 [inline] __se_sys_openat fs/open.c:1347 [inline] __x64_sys_openat+0x135/0x160 fs/open.c:1347 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: 0033:0x7f66a139e159 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:00007f669f5f6028 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007f66a1625fa0 RCX: 00007f66a139e159 RDX: 0000000000000002 RSI: 00002000000002c0 RDI: 0000000000000006 RBP: 00007f66a143506b R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f66a1626038 R14: 00007f66a1625fa0 R15: 00007ffdbc057a68