------------[ cut here ]------------ 1 WARNING: kernel/rcu/tree_stall.h:1049 at rcu_check_gp_start_stall.part.0+0x1c4/0x4b0 kernel/rcu/tree_stall.h:1049, CPU#1: swapper/1/0 Modules linked in: CPU: 1 UID: 0 PID: 0 Comm: swapper/1 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026 RIP: 0010:rcu_check_gp_start_stall.part.0+0x1c4/0x4b0 kernel/rcu/tree_stall.h:1049 Code: 88 61 01 00 00 be 04 00 00 00 48 c7 c7 c0 f2 f3 9a e8 a0 4c 85 00 b8 01 00 00 00 87 05 d5 ec 07 19 85 c0 0f 85 3d 01 00 00 90 <0f> 0b 90 48 c7 c3 d4 7c b7 90 48 81 fd 40 f3 5e 8e 74 5a 48 b8 00 RSP: 0018:ffffc90000a08df8 EFLAGS: 00010046 RAX: 0000000000000000 RBX: 0000000000002904 RCX: ffffffff81ec05e0 RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffffffff9af3f2c0 RBP: ffffffff8e5ef340 R08: 0000000000000001 R09: fffffbfff35e7e58 R10: 0000000000000003 R11: 0000000000000000 R12: 1ffffffff1c42250 R13: 0000000000000246 R14: ffffffff8e5ef340 R15: ffff8880b853bc52 FS: 0000000000000000(0000) GS:ffff8881246db000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fb58d9e8600 CR3: 00000000227a3000 CR4: 00000000003526f0 Call Trace: rcu_check_gp_start_stall kernel/rcu/tree_stall.h:1012 [inline] rcu_core+0x4e8/0x15c0 kernel/rcu/tree.c:2852 handle_softirqs+0x1ea/0x910 kernel/softirq.c:622 __do_softirq kernel/softirq.c:656 [inline] invoke_softirq kernel/softirq.c:496 [inline] __irq_exit_rcu+0xef/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+0xa3/0xc0 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+0xf/0x20 arch/x86/kernel/paravirt.c:82 Code: 56 78 02 c3 cc cc cc cc 0f 1f 00 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 83 ac 14 00 fb f4 fc 31 03 00 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90 RSP: 0018:ffffc90000197df0 EFLAGS: 00000242 RAX: 0000000006b44e75 RBX: ffff88801e2b24c0 RCX: ffffffff8b76d4b5 RDX: 0000000000000000 RSI: ffffffff8dc45690 RDI: ffffffff8bfa3620 RBP: 0000000000000001 R08: 0000000000000001 R09: ffffed10170a673d R10: ffff8880b85339eb R11: 0000000000000000 R12: ffffed1003c56498 R13: 0000000000000001 R14: ffffffff90b749d0 R15: 0000000000000000 arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline] default_idle+0x9/0x10 arch/x86/kernel/process.c:767 default_idle_call+0x6c/0xb0 kernel/sched/idle.c:122 cpuidle_idle_call kernel/sched/idle.c:191 [inline] do_idle+0x35b/0x4b0 kernel/sched/idle.c:332 cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:430 start_secondary+0x21d/0x2d0 arch/x86/kernel/smpboot.c:312 common_startup_64+0x13e/0x148 ---------------- Code disassembly (best guess): 0: 56 push %rsi 1: 78 02 js 0x5 3: c3 ret 4: cc int3 5: cc int3 6: cc int3 7: cc int3 8: 0f 1f 00 nopl (%rax) 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: 90 nop 17: 90 nop 18: 90 nop 19: 90 nop 1a: 90 nop 1b: f3 0f 1e fa endbr64 1f: 66 90 xchg %ax,%ax 21: 0f 00 2d 83 ac 14 00 verw 0x14ac83(%rip) # 0x14acab 28: fb sti 29: f4 hlt * 2a: e9 fc 31 03 00 jmp 0x3322b <-- trapping instruction 2f: 66 2e 0f 1f 84 00 00 cs nopw 0x0(%rax,%rax,1) 36: 00 00 00 39: 66 90 xchg %ax,%ax 3b: 90 nop 3c: 90 nop 3d: 90 nop 3e: 90 nop 3f: 90 nop