------------[ cut here ]------------ WARNING: CPU: 0 PID: 8754 at kernel/rcu/tree_stall.h:1001 rcu_check_gp_start_stall+0x2dc/0x460 kernel/rcu/tree_stall.h:993 Modules linked in: CPU: 0 PID: 8754 Comm: syz.7.727 Not tainted 6.6.97-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 RIP: 0010:rcu_check_gp_start_stall+0x2dc/0x460 kernel/rcu/tree_stall.h:1001 Code: ff ff ff 48 c7 c7 a0 f4 ee 96 be 04 00 00 00 e8 5a 21 6e 00 48 89 df b8 01 00 00 00 87 05 bc ce 7e 15 85 c0 0f 85 19 ff ff ff <0f> 0b 48 81 ff c0 52 d3 8c 74 47 48 c7 c0 9c c7 4a 8e 48 c1 e8 03 RSP: 0018:ffffc90000007bb8 EFLAGS: 00010046 RAX: 0000000000000000 RBX: ffffffff8cd352c0 RCX: ffffffff817025d6 RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffffffff8cd352c0 RBP: ffffc90000007e30 R08: 0000000000000003 R09: 0000000000000004 R10: dffffc0000000000 R11: fffffbfff2ddde94 R12: 0000000000002904 R13: 1ffff110171c7a6a R14: 0000000000000a02 R15: dffffc0000000000 FS: 00007fb7a50456c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fb7a43b5fa8 CR3: 000000005699e000 CR4: 00000000003506f0 Call Trace: rcu_core+0x612/0x1720 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+0xc7/0x190 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 9a 48 ef f6 48 89 df e8 b2 1a f0 f6 e8 9d c7 13 f7 fb bf 01 00 00 00 f2 31 e3 f6 65 8b 05 03 88 8b 75 85 c0 74 02 5b c3 e8 e0 69 88 RSP: 0018:ffffc900050b7c98 EFLAGS: 00000282 RAX: 7eac760f287efa00 RBX: ffff88802ca6dc80 RCX: 7eac760f287efa00 RDX: dffffc0000000000 RSI: ffffffff8aaab940 RDI: 0000000000000001 RBP: ffff88802ca6df18 R08: ffffffff8e4a92ef R09: 1ffffffff1c9525d R10: dffffc0000000000 R11: fffffbfff1c9525e R12: 1ffff1100594dbe3 R13: 0000000000000011 R14: dffffc0000000000 R15: 0000000000000000 spin_unlock_irq include/linux/spinlock.h:401 [inline] get_signal+0x11f5/0x1400 kernel/signal.c:2905 arch_do_signal_or_restart+0x96/0x780 arch/x86/kernel/signal.c:310 exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174 exit_to_user_mode_prepare+0xb1/0x140 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+0x61/0xb0 arch/x86/entry/common.c:87 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7fb7a418e929 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fb7a50450e8 EFLAGS: 00000246 RAX: fffffffffffffffc RBX: 00007fb7a43b5fa8 RCX: 00007fb7a418e929 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007fb7a43b5fa8 RBP: 00007fb7a43b5fa0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fb7a43b5fac R13: 0000000000000000 R14: 00007ffdd6234360 R15: 00007ffdd6234448 ---------------- 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 9a 48 ef f6 call 0xf6ef48b1 17: 48 89 df mov %rbx,%rdi 1a: e8 b2 1a f0 f6 call 0xf6f01ad1 1f: e8 9d c7 13 f7 call 0xf713c7c1 24: fb sti 25: bf 01 00 00 00 mov $0x1,%edi * 2a: e8 f2 31 e3 f6 call 0xf6e33221 <-- trapping instruction 2f: 65 8b 05 03 88 8b 75 mov %gs:0x758b8803(%rip),%eax # 0x758b8839 36: 85 c0 test %eax,%eax 38: 74 02 je 0x3c 3a: 5b pop %rbx 3b: c3 ret 3c: e8 .byte 0xe8 3d: e0 69 loopne 0xa8 3f: 88 .byte 0x88