------------[ cut here ]------------ WARNING: CPU: 1 PID: 6136 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: 6136 Comm: syz.0.87 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 RIP: 0010:rcu_check_gp_start_stall+0x2dc/0x460 kernel/rcu/tree_stall.h:1001 Code: ff ff ff 48 c7 c7 a0 14 ef 96 be 04 00 00 00 e8 7a bb 6c 00 48 89 df b8 01 00 00 00 87 05 bc e4 7e 15 85 c0 0f 85 19 ff ff ff <0f> 0b 48 81 ff 80 51 d3 8c 74 47 48 c7 c0 1c c0 4a 8e 48 c1 e8 03 RSP: 0018:ffffc900001f0bb8 EFLAGS: 00010046 RAX: 0000000000000000 RBX: ffffffff8cd35180 RCX: ffffffff81702fd6 RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffffffff8cd35180 RBP: ffffc900001f0e30 R08: 0000000000000003 R09: 0000000000000004 R10: dffffc0000000000 R11: fffffbfff2dde294 R12: 0000000000002904 R13: 1ffff110171e7a22 R14: 0000000000000a02 R15: dffffc0000000000 FS: 00007f581234a6c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f58117e6098 CR3: 000000005bef4000 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:raw_spin_rq_unlock_irq+0x13/0x90 kernel/sched/sched.h:1385 Code: 0f 48 8d 65 d8 5b 41 5c 41 5d 41 5e 41 5f 5d c3 e8 42 0c 11 09 66 90 41 57 41 56 53 eb 11 e8 74 b4 1a 09 e8 1f 32 2e 00 fb 5b <41> 5e 41 5f c3 f3 0f 1e fa 49 be 00 00 00 00 00 fc ff df 49 89 ff RSP: 0018:ffffc900054c7c88 EFLAGS: 00000282 RAX: 5bf0894e3ba5d000 RBX: ffff8880b8f3cf48 RCX: 5bf0894e3ba5d000 RDX: dffffc0000000000 RSI: ffffffff8aaabd60 RDI: ffffffff8afc6bc0 RBP: ffffc900054c7ea0 R08: ffffffff8e4a8b6f R09: 1ffffffff1c9516d R10: dffffc0000000000 R11: fffffbfff1c9516e R12: dffffc0000000000 R13: ffff8880b8f3c200 R14: dffffc0000000000 R15: ffff8880b8f3cf48 __schedule+0x171e/0x44d0 kernel/sched/core.c:6703 schedule+0xbd/0x170 kernel/sched/core.c:6773 exit_to_user_mode_loop+0x47/0x110 kernel/entry/common.c:165 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: 0033:0x7f581158efc9 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:00007f581234a0e8 EFLAGS: 00000246 RAX: fffffffffffffffc RBX: 00007f58117e6098 RCX: 00007f581158efc9 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f58117e6098 RBP: 00007f58117e6090 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f58117e6128 R14: 00007ffcc4054a10 R15: 00007ffcc4054af8 ---------------- Code disassembly (best guess): 0: 0f 48 8d 65 d8 5b 41 cmovs 0x415bd865(%rbp),%ecx 7: 5c pop %rsp 8: 41 5d pop %r13 a: 41 5e pop %r14 c: 41 5f pop %r15 e: 5d pop %rbp f: c3 ret 10: e8 42 0c 11 09 call 0x9110c57 15: 66 90 xchg %ax,%ax 17: 41 57 push %r15 19: 41 56 push %r14 1b: 53 push %rbx 1c: eb 11 jmp 0x2f 1e: e8 74 b4 1a 09 call 0x91ab497 23: e8 1f 32 2e 00 call 0x2e3247 28: fb sti 29: 5b pop %rbx * 2a: 41 5e pop %r14 <-- trapping instruction 2c: 41 5f pop %r15 2e: c3 ret 2f: f3 0f 1e fa endbr64 33: 49 be 00 00 00 00 00 movabs $0xdffffc0000000000,%r14 3a: fc ff df 3d: 49 89 ff mov %rdi,%r15