rcu: INFO: rcu_preempt detected expedited stalls on CPUs/tasks: { 1-.... } 2660 jiffies s: 49793 root: 0x2/. rcu: blocking rcu_node structures (internal RCU debug): Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 16717 Comm: syz.0.4023 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026 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_cmp8+0x1b/0x80 kernel/kcov.c:320 Code: 7c 11 10 48 89 74 11 18 48 89 44 11 20 c3 90 48 8b 04 24 65 48 8b 0d 04 f6 7f 7e 65 8b 15 05 f6 7f 7e 81 e2 00 01 ff 00 74 11 <81> fa 00 01 00 00 75 57 83 b9 1c 16 00 00 00 74 4e 8b 91 f8 15 00 RSP: 0018:ffffc900001dff78 EFLAGS: 00000006 RAX: ffffffff8100fdbd RBX: 1ffff9200003c021 RCX: ffff88805c658000 RDX: 0000000000000100 RSI: ffffffff8171c074 RDI: 0000000000000000 RBP: ffffc900001e00b0 R08: ffffc900001e0aa0 R09: ffffc900001e0030 R10: dffffc0000000000 R11: fffff5200003c008 R12: ffffc900001e010c R13: ffffc900001dffe0 R14: ffffffff8171c074 R15: 1ffff9200003bff8 FS: 00007f87344186c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000100000000 CR3: 0000000076f7a000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000200000000300 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff3 DR7: 0000000000000600 Call Trace: perf_callchain_kernel+0x30d/0x680 arch/x86/events/core.c:2807 get_perf_callchain+0x236/0x490 kernel/events/callchain.c:204 perf_callchain kernel/events/core.c:7512 [inline] perf_prepare_sample+0x399/0x2020 kernel/events/core.c:7545 __perf_event_output kernel/events/core.c:7730 [inline] perf_event_output_forward+0x197/0x2f0 kernel/events/core.c:7750 __perf_event_overflow+0x448/0x610 kernel/events/core.c:9496 perf_swevent_overflow kernel/events/core.c:9579 [inline] perf_swevent_event+0x315/0x570 kernel/events/core.c:9630 perf_tp_event+0x3e7/0xc30 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_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691 RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline] RIP: 0010:_raw_spin_unlock_irqrestore+0xbc/0x120 kernel/locking/spinlock.c:194 Code: c7 44 24 20 00 00 00 00 9c 8f 44 24 20 f7 44 24 20 00 02 00 00 41 c6 04 07 f8 75 4b f7 c3 00 02 00 00 74 01 fb bf 01 00 00 00 2f ed 20 f7 65 8b 05 80 70 ca 75 85 c0 74 3c 48 c7 04 24 0e 36 RSP: 0018:ffffc900001e09a0 EFLAGS: 00000206 RAX: dffffc0000000004 RBX: 0000000000000a02 RCX: b001b454cc0f8300 RDX: dffffc0000000000 RSI: ffffffff8a8c1120 RDI: 0000000000000001 RBP: ffffc900001e0a20 R08: ffffffff90af9327 R09: 1ffffffff215f264 R10: dffffc0000000000 R11: fffffbfff215f265 R12: dffffc0000000000 R13: ffff88806400d230 R14: ffffffff96e52260 R15: 1ffff9200003c134 debug_object_assert_init+0x1ed/0x2f0 lib/debugobjects.c:889 debug_timer_assert_init kernel/time/timer.c:792 [inline] debug_assert_init kernel/time/timer.c:837 [inline] __mod_timer+0x54/0xd00 kernel/time/timer.c:1020 mrp_join_timer_arm net/802/mrp.c:596 [inline] mrp_join_timer+0x13b/0x170 net/802/mrp.c:611 call_timer_fn+0x1ac/0x670 kernel/time/timer.c:1701 expire_timers kernel/time/timer.c:1752 [inline] __run_timers+0x53e/0x800 kernel/time/timer.c:2023 run_timer_softirq+0x63/0xf0 kernel/time/timer.c:2036 handle_softirqs+0x2a1/0x930 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:preempt_schedule_irq+0xb6/0x160 kernel/sched/core.c:6874 Code: 00 00 43 c6 44 37 04 f8 74 0b 0f 0b 48 f7 03 08 00 00 00 74 7f bf 01 00 00 00 e8 15 64 22 f7 e8 10 58 52 f7 fb bf 01 00 00 00 75 b9 ff ff 43 c6 44 37 08 00 48 c7 44 24 40 00 00 00 00 9c 8f RSP: 0018:ffffc9000ca9fb80 EFLAGS: 00000282 RAX: b001b454cc0f8300 RBX: 0000000000000000 RCX: b001b454cc0f8300 RDX: dffffc0000000000 RSI: ffffffff8a8c1120 RDI: 0000000000000001 RBP: ffffc9000ca9fc20 R08: ffff8880b8f3580b R09: 1ffff110171e6b01 R10: dffffc0000000000 R11: ffffed10171e6b02 R12: 0000000000000000 R13: 0000000000000000 R14: dffffc0000000000 R15: 1ffff92001953f70 irqentry_exit+0x63/0x70 kernel/entry/common.c:439 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691 RIP: 0010:__ref_is_percpu include/linux/percpu-refcount.h:174 [inline] RIP: 0010:percpu_ref_tryget_many include/linux/percpu-refcount.h:243 [inline] RIP: 0010:percpu_ref_tryget+0x8e/0x180 include/linux/percpu-refcount.h:266 Code: 61 98 8a be 19 03 00 00 48 c7 c2 40 61 98 8a e8 08 1a 8a ff 49 bf 00 00 00 00 00 fc ff df 4c 89 f0 48 c1 e8 03 42 80 3c 38 00 <74> 08 4c 89 f7 e8 48 ad f8 ff 49 8b 06 a8 03 75 67 65 48 ff 00 40 RSP: 0018:ffffc9000ca9fce8 EFLAGS: 00000246 RAX: 1ffff110048f3c00 RBX: ffffffff81dad3c5 RCX: b001b454cc0f8300 RDX: 0000000000000000 RSI: ffffffff8adf1300 RDI: ffffffff8adf12c0 RBP: 0000000000000cc0 R08: dffffc0000000000 R09: 1ffffffff215f248 R10: dffffc0000000000 R11: fffffbfff215f249 R12: ffff88814011c860 R13: 0000000000000580 R14: ffff88802479e000 R15: dffffc0000000000 obj_cgroup_tryget include/linux/memcontrol.h:779 [inline] __get_obj_cgroup_from_memcg+0x70/0xe0 mm/memcontrol.c:3004 get_obj_cgroup_from_current+0x16b/0x280 mm/memcontrol.c:3024 memcg_slab_pre_alloc_hook mm/slab.h:485 [inline] slab_pre_alloc_hook+0x91/0x310 mm/slab.h:715 slab_alloc_node mm/slub.c:3279 [inline] slab_alloc mm/slub.c:3367 [inline] __kmem_cache_alloc_lru mm/slub.c:3374 [inline] kmem_cache_alloc_lru+0x49/0x2e0 mm/slub.c:3390 alloc_inode_sb include/linux/fs.h:3245 [inline] sock_alloc_inode+0x24/0xc0 net/socket.c:306 alloc_inode fs/inode.c:261 [inline] new_inode_pseudo+0x5f/0x1c0 fs/inode.c:1063 sock_alloc net/socket.c:631 [inline] __sock_create+0x129/0x940 net/socket.c:1513 sock_create net/socket.c:1605 [inline] __sys_socket_create net/socket.c:1642 [inline] __sys_socket+0xc4/0x190 net/socket.c:1670 __do_sys_socket net/socket.c:1683 [inline] __se_sys_socket net/socket.c:1681 [inline] __x64_sys_socket+0x76/0x80 net/socket.c:1681 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: 0033:0x7f873359cdd9 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:00007f8734418028 EFLAGS: 00000246 ORIG_RAX: 0000000000000029 RAX: ffffffffffffffda RBX: 00007f8733815fa0 RCX: 00007f873359cdd9 RDX: 0000000000000000 RSI: 0000000000000002 RDI: 000000000000000a RBP: 00007f8733632d69 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f8733816038 R14: 00007f8733815fa0 R15: 00007fff2e7b9c08