rcu: INFO: rcu_preempt detected expedited stalls on CPUs/tasks: { 0-.... } 13163 jiffies s: 669 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: 0 Comm: swapper/0 Not tainted 6.6.101-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 RIP: 0010:__sanitizer_cov_trace_pc+0x0/0x60 kernel/kcov.c:212 Code: 00 0f 0b 0f 1f 80 00 00 00 00 f3 0f 1e fa 53 48 89 fb e8 13 00 00 00 48 8b 3d 8c f1 c4 0c 48 89 de 5b e9 63 75 56 00 cc cc cc 0f 1e fa 48 8b 04 24 65 48 8b 0d 60 24 7e 7e 65 8b 15 61 24 7e RSP: 0018:ffffc90000007448 EFLAGS: 00000246 RAX: 0000000000000020 RBX: 0000000000000004 RCX: 0000000000000005 RDX: ffffffff81876025 RSI: ffffffff8cd79100 RDI: 0000000000000004 RBP: 0000000000000f00 R08: ffffffff8ca93380 R09: 0000000000000020 R10: 000000000000001f R11: 0000000000000100 R12: dffffc0000000000 R13: f800000000000000 R14: ffff88801824272c R15: 0000000000095bc4 FS: 0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00002000000018c0 CR3: 0000000071440000 CR4: 00000000003506f0 Call Trace: rb_event_length+0x148/0x3f0 kernel/trace/ring_buffer.c:198 check_buffer+0x542/0x950 kernel/trace/ring_buffer.c:3491 __rb_reserve_next+0x511/0xd50 kernel/trace/ring_buffer.c:3624 rb_reserve_next_event kernel/trace/ring_buffer.c:3759 [inline] ring_buffer_lock_reserve+0xae1/0xed0 kernel/trace/ring_buffer.c:3818 __trace_buffer_lock_reserve kernel/trace/trace.c:992 [inline] trace_event_buffer_lock_reserve+0x1d0/0x6e0 kernel/trace/trace.c:2902 trace_event_buffer_reserve+0x29b/0x3c0 kernel/trace/trace_events.c:661 do_trace_event_raw_event_bpf_trace_printk kernel/trace/bpf_trace.h:11 [inline] trace_event_raw_event_bpf_trace_printk+0x101/0x210 kernel/trace/bpf_trace.h:11 trace_bpf_trace_printk+0x142/0x1a0 kernel/trace/bpf_trace.h:11 ____bpf_trace_printk kernel/trace/bpf_trace.c:388 [inline] bpf_trace_printk+0x11f/0x190 kernel/trace/bpf_trace.c:371 bpf_prog_9e1c00255e17e72e+0x38/0x3a bpf_dispatcher_nop_func include/linux/bpf.h:1213 [inline] __bpf_prog_run include/linux/filter.h:612 [inline] bpf_prog_run include/linux/filter.h:619 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:2322 [inline] bpf_trace_run1+0x1c9/0x3b0 kernel/trace/bpf_trace.c:2360 __bpf_trace_rcu_utilization+0xa2/0xe0 include/trace/events/rcu.h:27 __traceiter_rcu_utilization+0x70/0xa0 include/trace/events/rcu.h:27 trace_rcu_utilization+0x179/0x1a0 include/trace/events/rcu.h:27 rcu_core+0x12d/0x1720 kernel/rcu/tree.c:2439 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+0xc7/0x190 kernel/softirq.c:661 irq_exit_rcu+0x9/0x20 kernel/softirq.c:673 instr_sysvec_irq_work arch/x86/kernel/irq_work.c:17 [inline] sysvec_irq_work+0xa1/0xc0 arch/x86/kernel/irq_work.c:17 asm_sysvec_irq_work+0x1a/0x20 arch/x86/include/asm/idtentry.h:723 RIP: 0010:pv_native_safe_halt+0x13/0x20 arch/x86/kernel/paravirt.c:148 Code: cc cc cc cc cc cc cc f3 0f 1e fa 0f 0b 66 2e 0f 1f 84 00 00 00 00 00 f3 0f 1e fa 66 90 0f 00 2d 83 16 3b 00 f3 0f 1e fa fb f4 cc cc cc cc cc cc cc cc cc cc cc cc 66 0f 1f 00 55 41 57 41 56 RSP: 0018:ffffffff8ca07d80 EFLAGS: 000002c2 RAX: f2ce17b852f16400 RBX: ffffffff81619a6b RCX: f2ce17b852f16400 RDX: 0000000000000001 RSI: ffffffff8aaaba40 RDI: ffffffff8afc6780 RBP: ffffffff8ca07eb8 R08: ffff8880b8e36d4b R09: 1ffff110171c6da9 R10: dffffc0000000000 R11: ffffed10171c6daa R12: ffffffff8e4a84e8 R13: 0000000000000000 R14: 0000000000000000 R15: 1ffffffff1952670 arch_safe_halt arch/x86/include/asm/paravirt.h:108 [inline] default_idle+0x13/0x20 arch/x86/kernel/process.c:753 default_idle_call+0x6c/0xa0 kernel/sched/idle.c:97 cpuidle_idle_call kernel/sched/idle.c:170 [inline] do_idle+0x1eb/0x510 kernel/sched/idle.c:282 cpu_startup_entry+0x43/0x60 kernel/sched/idle.c:380 rest_init+0x2e2/0x300 init/main.c:732 arch_call_rest_init+0xe/0x10 init/main.c:829 start_kernel+0x459/0x4e0 init/main.c:1074 x86_64_start_reservations+0x2a/0x30 arch/x86/kernel/head64.c:555 x86_64_start_kernel+0x60/0x60 arch/x86/kernel/head64.c:536 secondary_startup_64_no_verify+0x179/0x17b INFO: NMI handler (nmi_cpu_backtrace_handler) took too long to run: 1.975 msecs