------------[ cut here ]------------ WARNING: CPU: 1 PID: 6840 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: 6840 Comm: syz.0.274 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 RIP: 0010:rcu_check_gp_start_stall+0x2dc/0x460 kernel/rcu/tree_stall.h:1001 Code: ff ff ff 48 c7 c7 a0 24 ef 96 be 04 00 00 00 e8 4a d0 6c 00 48 89 df b8 01 00 00 00 87 05 4c f4 7e 15 85 c0 0f 85 19 ff ff ff <0f> 0b 48 81 ff 80 51 d3 8c 74 47 48 c7 c0 ac c8 4a 8e 48 c1 e8 03 RSP: 0018:ffffc900001f0bb8 EFLAGS: 00010046 RAX: 0000000000000000 RBX: ffffffff8cd35180 RCX: ffffffff81703046 RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffffffff8cd35180 RBP: ffffc900001f0e30 R08: 0000000000000003 R09: 0000000000000004 R10: dffffc0000000000 R11: fffffbfff2dde494 R12: 0000000000002904 R13: 1ffff110171e79e2 R14: 0000000000000a02 R15: dffffc0000000000 FS: 00007f59c697f6c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fc6dfeb1f40 CR3: 0000000031bf7000 CR4: 00000000003506e0 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:signal_setup_done+0x23b/0x310 kernel/signal.c:2951 Code: 75 3e bf 05 00 00 00 31 f6 48 83 c4 18 5b 41 5c 41 5d 41 5e 41 5f 5d e9 93 c5 ff ff e8 6e 67 31 00 65 48 8b 04 25 28 00 00 00 <48> 3b 44 24 10 75 0f 48 83 c4 18 5b 41 5c 41 5d 41 5e 41 5f 5d c3 RSP: 0018:ffffc9000c26fd30 EFLAGS: 00000293 RAX: 09e868c1108b3800 RBX: 0000000000000000 RCX: ffff88802c948000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000002 R08: ffffffff8e4a93ef R09: 1ffffffff1c9527d R10: dffffc0000000000 R11: fffffbfff1c9527e R12: 1ffff1100592912c R13: 0000000100000000 R14: ffff88802c948000 R15: ffff88802c948960 handle_signal arch/x86/kernel/signal.c:285 [inline] arch_do_signal_or_restart+0x4a6/0x7b0 arch/x86/kernel/signal.c:312 exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174 exit_to_user_mode_prepare+0xf6/0x180 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+0x61/0xb0 arch/x86/entry/common.c:87 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f59c5bb7e80 Code: 83 c0 16 83 e0 f7 74 12 50 48 8d 3d 8a 54 08 00 e8 05 8f f8 ff 0f 1f 44 00 00 c3 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 <83> ff 21 74 0b c3 66 2e 0f 1f 84 00 00 00 00 00 55 53 48 89 f3 48 RSP: 002b:00007f59c697ea78 EFLAGS: 00000246 ORIG_RAX: 0000000000000013 RAX: 0000000000000000 RBX: 00007f59c5de5fa0 RCX: 00007f59c5b8f749 RDX: 00007f59c697ea80 RSI: 00007f59c697ebb0 RDI: 0000000000000021 RBP: 00007f59c5c13f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f59c5de6038 R14: 00007f59c5de5fa0 R15: 00007ffc1c049258 ---------------- Code disassembly (best guess): 0: 75 3e jne 0x40 2: bf 05 00 00 00 mov $0x5,%edi 7: 31 f6 xor %esi,%esi 9: 48 83 c4 18 add $0x18,%rsp d: 5b pop %rbx e: 41 5c pop %r12 10: 41 5d pop %r13 12: 41 5e pop %r14 14: 41 5f pop %r15 16: 5d pop %rbp 17: e9 93 c5 ff ff jmp 0xffffc5af 1c: e8 6e 67 31 00 call 0x31678f 21: 65 48 8b 04 25 28 00 mov %gs:0x28,%rax 28: 00 00 * 2a: 48 3b 44 24 10 cmp 0x10(%rsp),%rax <-- trapping instruction 2f: 75 0f jne 0x40 31: 48 83 c4 18 add $0x18,%rsp 35: 5b pop %rbx 36: 41 5c pop %r12 38: 41 5d pop %r13 3a: 41 5e pop %r14 3c: 41 5f pop %r15 3e: 5d pop %rbp 3f: c3 ret