------------[ cut here ]------------ WARNING: CPU: 1 PID: 5908 at kernel/rcu/tree_stall.h:1001 rcu_check_gp_start_stall+0x2dc/0x460 kernel/rcu/tree_stall.h:993 Modules linked in: CPU: 1 PID: 5908 Comm: syz.1.21 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026 RIP: 0010:rcu_check_gp_start_stall+0x2dc/0x460 kernel/rcu/tree_stall.h:1001 Code: ff ff ff 48 c7 c7 a0 f4 30 97 be 04 00 00 00 e8 fa dd 6d 00 48 89 df b8 01 00 00 00 87 05 7c 77 bf 15 85 c0 0f 85 19 ff ff ff <0f> 0b 48 81 ff 40 73 13 8d 74 47 48 c7 c0 6c 4e 8b 8e 48 c1 e8 03 RSP: 0018:ffffc900001f0bb8 EFLAGS: 00010046 RAX: 0000000000000000 RBX: ffffffff8d137340 RCX: ffffffff81717d16 RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffffffff8d137340 RBP: ffffc900001f0e30 R08: 0000000000000003 R09: 0000000000000004 R10: dffffc0000000000 R11: fffffbfff2e61e94 R12: 0000000000002904 R13: ffffffff8d137340 R14: 0000000000000a02 R15: dffffc0000000000 FS: 00007f17bdf1c6c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000020000006b000 CR3: 000000002fe90000 CR4: 00000000003526e0 Call Trace: rcu_core+0x635/0x1770 kernel/rcu/tree.c:2462 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+0xd3/0x190 kernel/softirq.c:661 irq_exit_rcu+0x9/0x20 kernel/softirq.c:673 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1088 [inline] sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1088 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687 RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:160 [inline] RIP: 0010:_raw_spin_unlock_irq+0x29/0x50 kernel/locking/spinlock.c:202 Code: 00 f3 0f 1e fa 53 48 89 fb 48 83 c7 18 48 8b 74 24 08 e8 ea 97 d8 f6 48 89 df e8 a2 6c d9 f6 e8 1d 7f fd f6 fb bf 01 00 00 00 82 73 cc f6 65 8b 05 c3 a0 73 75 85 c0 74 02 5b c3 e8 40 88 70 RSP: 0018:ffffc9000487fc78 EFLAGS: 00000286 RAX: 6e773e2e8e569d00 RBX: ffff88802c0adc80 RCX: 6e773e2e8e569d00 RDX: dffffc0000000000 RSI: ffffffff8acac9e0 RDI: 0000000000000001 RBP: ffff88802c0ae118 R08: ffffffff8e8b19af R09: 1ffffffff1d16335 R10: dffffc0000000000 R11: fffffbfff1d16336 R12: 1ffff11005815c23 R13: 0000000000000021 R14: dffffc0000000000 R15: 0000000000000000 spin_unlock_irq include/linux/spinlock.h:401 [inline] get_signal+0x11f5/0x13f0 kernel/signal.c:2905 arch_do_signal_or_restart+0xc2/0x800 arch/x86/kernel/signal.c:310 exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline] syscall_exit_to_user_mode+0x1a/0x50 kernel/entry/common.c:302 do_syscall_64+0x61/0xa0 arch/x86/entry/common.c:82 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f17bcf9cdd7 Code: 83 c8 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 RSP: 002b:00007f17bdf1c0e8 EFLAGS: 00000246 RAX: 00000000000000ca RBX: 00007f17bd215fa8 RCX: 00007f17bcf9cdd9 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f17bd215fa8 RBP: 00007f17bd215fa0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f17bd216038 R14: 00007ffeae3ab0d0 R15: 00007ffeae3ab1b8 ---------------- Code disassembly (best guess): 0: 00 f3 add %dh,%bl 2: 0f 1e fa nop %edx 5: 53 push %rbx 6: 48 89 fb mov %rdi,%rbx 9: 48 83 c7 18 add $0x18,%rdi d: 48 8b 74 24 08 mov 0x8(%rsp),%rsi 12: e8 ea 97 d8 f6 call 0xf6d89801 17: 48 89 df mov %rbx,%rdi 1a: e8 a2 6c d9 f6 call 0xf6d96cc1 1f: e8 1d 7f fd f6 call 0xf6fd7f41 24: fb sti 25: bf 01 00 00 00 mov $0x1,%edi * 2a: e8 82 73 cc f6 call 0xf6cc73b1 <-- trapping instruction 2f: 65 8b 05 c3 a0 73 75 mov %gs:0x7573a0c3(%rip),%eax # 0x7573a0f9 36: 85 c0 test %eax,%eax 38: 74 02 je 0x3c 3a: 5b pop %rbx 3b: c3 ret 3c: e8 .byte 0xe8 3d: 40 rex 3e: 88 .byte 0x88 3f: 70 .byte 0x70