------------[ cut here ]------------ WARNING: kernel/rcu/tree_stall.h:1049 at rcu_check_gp_start_stall+0x2e4/0x470 kernel/rcu/tree_stall.h:1049, CPU#0: swapper/0/0 Modules linked in: CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 RIP: 0010:rcu_check_gp_start_stall+0x2e4/0x470 kernel/rcu/tree_stall.h:1049 Code: ff ff 48 c7 c7 a0 85 8f 99 be 04 00 00 00 e8 b3 8d 7f 00 4c 89 f7 b8 01 00 00 00 87 05 b5 f8 e7 17 85 c0 0f 85 17 ff ff ff 90 <0f> 0b 90 48 81 ff 80 6e f4 8d 74 47 48 c7 c0 a0 55 82 8f 48 c1 e8 RSP: 0018:ffffc90000007d98 EFLAGS: 00010046 RAX: 0000000000000000 RBX: 0000000000000246 RCX: ffffffff81a78cdd RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffffffff8df46e80 RBP: ffffc90000007f30 R08: 0000000000000003 R09: 0000000000000004 R10: dffffc0000000000 R11: fffffbfff331f0b4 R12: 0000000000002904 R13: 1ffff110170c771a R14: ffffffff8df46e80 R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff888125e1f000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000110c2e624f CR3: 0000000067346000 CR4: 0000000000350ef0 Call Trace: rcu_core+0x5f5/0x1720 kernel/rcu/tree.c:2852 handle_softirqs+0x22b/0x7c0 kernel/softirq.c:622 __do_softirq kernel/softirq.c:656 [inline] invoke_softirq kernel/softirq.c:496 [inline] __irq_exit_rcu+0x60/0x150 kernel/softirq.c:723 irq_exit_rcu+0x9/0x30 kernel/softirq.c:739 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1056 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:pv_native_safe_halt+0x13/0x20 arch/x86/kernel/paravirt.c:82 Code: 1e a4 b6 f5 cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d 53 b1 0e 00 f3 0f 1e fa fb f4 f3 a3 b6 f5 cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90 RSP: 0018:ffffffff8dc07dc0 EFLAGS: 000002c6 RAX: 0000000000eba419 RBX: ffffffff819713ee RCX: 0000000080000001 RDX: 0000000000000001 RSI: ffffffff8d792134 RDI: ffffffff8bc083e0 RBP: ffffffff8dc07eb0 R08: ffff8880b86336db R09: 1ffff110170c66db R10: dffffc0000000000 R11: ffffed10170c66dc R12: ffffffff8f822570 R13: 1ffffffff1b92a68 R14: 0000000000000000 R15: 0000000000000000 arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline] default_idle+0x13/0x20 arch/x86/kernel/process.c:767 default_idle_call+0x73/0xb0 kernel/sched/idle.c:122 cpuidle_idle_call kernel/sched/idle.c:191 [inline] do_idle+0x1be/0x4d0 kernel/sched/idle.c:332 cpu_startup_entry+0x44/0x60 kernel/sched/idle.c:430 rest_init+0x2de/0x300 init/main.c:757 start_kernel+0x381/0x3d0 init/main.c:1206 x86_64_start_reservations+0x24/0x30 arch/x86/kernel/head64.c:310 x86_64_start_kernel+0x143/0x1c0 arch/x86/kernel/head64.c:291 common_startup_64+0x13e/0x147 ---------------- Code disassembly (best guess), 1 bytes skipped: 0: a4 movsb %ds:(%rsi),%es:(%rdi) 1: b6 f5 mov $0xf5,%dh 3: cc int3 4: cc int3 5: cc int3 6: 90 nop 7: 90 nop 8: 90 nop 9: 90 nop a: 90 nop b: 90 nop c: 90 nop d: 90 nop e: 90 nop f: 90 nop 10: 90 nop 11: 90 nop 12: 90 nop 13: 90 nop 14: 90 nop 15: 90 nop 16: f3 0f 1e fa endbr64 1a: 66 90 xchg %ax,%ax 1c: 0f 00 2d 53 b1 0e 00 verw 0xeb153(%rip) # 0xeb176 23: f3 0f 1e fa endbr64 27: fb sti 28: f4 hlt * 29: e9 f3 a3 b6 f5 jmp 0xf5b6a421 <-- trapping instruction 2e: cc int3 2f: cc int3 30: cc int3 31: cc int3 32: cc int3 33: cc int3 34: cc int3 35: cc int3 36: 90 nop 37: 90 nop 38: 90 nop 39: 90 nop 3a: 90 nop 3b: 90 nop 3c: 90 nop 3d: 90 nop 3e: 90 nop