rcu: INFO: rcu_preempt detected expedited stalls on CPUs/tasks: { 1-.... } 2673 jiffies s: 14905 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: 5043 Comm: syz.4.183 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026 RIP: 0010:preempt_count arch/x86/include/asm/preempt.h:27 [inline] RIP: 0010:check_kcov_mode kernel/kcov.c:182 [inline] RIP: 0010:__sanitizer_cov_trace_pc+0xc/0x60 kernel/kcov.c:216 Code: 89 fb e8 17 00 00 00 48 8b 3d 90 6c 9d 0c 48 89 de 5b e9 97 41 50 00 00 00 cc cc 00 00 cc 48 8b 04 24 65 48 8b 0d a4 fa 7f 7e <65> 8b 15 a5 fa 7f 7e 81 e2 00 01 ff 00 74 11 81 fa 00 01 00 00 75 RSP: 0018:ffffc900001e0460 EFLAGS: 00000002 RAX: ffffffff818ecb68 RBX: 0000000000000102 RCX: ffff8880187a3b80 RDX: ffff8880187a3b80 RSI: 0000000000000102 RDI: 0000000000000000 RBP: 0000000000000001 R08: ffffc900001e03c7 R09: 1ffff9200003c078 R10: dffffc0000000000 R11: fffff5200003c079 R12: 0000000000000000 R13: dffffc0000000001 R14: 0000000000000000 R15: 0000000000000001 FS: 00007f71973a86c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b2f81cff8 CR3: 0000000078b9d000 CR4: 00000000003506e0 DR0: 0000200000000300 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600 Call Trace: irq_work_queue_on+0x198/0x260 kernel/irq_work.c:168 rcu_read_unlock_special+0x3c9/0x510 kernel/rcu/tree_plugin.h:678 __rcu_read_unlock+0x78/0xd0 kernel/rcu/tree_plugin.h:426 rcu_read_unlock include/linux/rcupdate.h:823 [inline] __perf_event_output kernel/events/core.c:7741 [inline] perf_event_output_forward+0x271/0x2f0 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_irq_work+0x16/0x20 arch/x86/include/asm/idtentry.h:728 RIP: 0010:rcu_read_unlock_special+0x0/0x510 kernel/rcu/tree_plugin.h:630 Code: c6 44 66 00 eb b0 44 89 f1 80 e1 07 80 c1 03 38 c1 7c 94 49 89 fd 4c 89 f7 e8 ac 44 66 00 4c 89 ef eb 84 0f 1f 80 00 00 00 00 <55> 48 89 e5 41 57 41 56 41 55 41 54 53 48 83 e4 e0 48 81 ec c0 00 RSP: 0018:ffffc900001e0d10 EFLAGS: 00000206 RAX: 0000000000000000 RBX: ffff8880187a3fbc RCX: 198940ac8a808700 RDX: 0000000000000001 RSI: ffffffff8adf0d00 RDI: ffff8880187a3b80 RBP: 0000000000000997 R08: dffffc0000000000 R09: fffff5200003c140 R10: dffffc0000000000 R11: fffff5200003c172 R12: 1ffff110030f47f7 R13: 0000000000000000 R14: ffff8880187a3fc0 R15: dffffc0000000000 __rcu_read_unlock+0x78/0xd0 kernel/rcu/tree_plugin.h:426 rcu_read_unlock include/linux/rcupdate.h:823 [inline] rebalance_domains+0x8da/0xa10 kernel/sched/fair.c:11051 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:finish_task_switch+0x26a/0x8f0 kernel/sched/core.c:5124 Code: 0f 84 3b 01 00 00 48 85 db 0f 85 5a 01 00 00 0f 1f 44 00 00 4c 8b 75 d0 4c 89 e7 e8 00 2c de 08 e8 8b 2c 2f 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:ffffc9000d5778f8 EFLAGS: 00000282 RAX: 198940ac8a808700 RBX: 0000000000000000 RCX: 198940ac8a808700 RDX: dffffc0000000000 RSI: ffffffff8a8c10a0 RDI: ffffffff8adf0d20 RBP: ffffc9000d577950 R08: ffff8880b8f3580b R09: 1ffff110171e6b01 R10: dffffc0000000000 R11: ffffed10171e6b02 R12: ffff8880187a3b80 R13: dffffc0000000000 R14: ffff88813fee1dc0 R15: ffff8880b8f3b5d0 context_switch kernel/sched/core.c:5248 [inline] __schedule+0x11d9/0x40e0 kernel/sched/core.c:6562 schedule+0xb9/0x180 kernel/sched/core.c:6638 futex_wait_queue+0x134/0x1b0 kernel/futex/waitwake.c:355 futex_wait+0x1e8/0x5e0 kernel/futex/waitwake.c:656 do_futex+0x310/0x320 kernel/futex/syscalls.c:134 __do_sys_futex kernel/futex/syscalls.c:211 [inline] __se_sys_futex+0x381/0x410 kernel/futex/syscalls.c:192 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: 0033:0x7f719659c819 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:00007f71973a80e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: ffffffffffffffda RBX: 00007f7196815fa8 RCX: 00007f719659c819 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f7196815fa8 RBP: 00007f7196815fa0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f7196816038 R14: 00007ffcea6aa410 R15: 00007ffcea6aa4f8