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WARNING: kernel/rcu/tree_stall.h:1049 at rcu_check_gp_start_stall+0x2e4/0x470 kernel/rcu/tree_stall.h:1049, CPU#1: syz.6.4373/16873
Modules linked in:
CPU: 1 UID: 0 PID: 16873 Comm: syz.6.4373 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
RIP: 0010:rcu_check_gp_start_stall+0x2e4/0x470 kernel/rcu/tree_stall.h:1049
Code: ff ff 48 c7 c7 c0 b4 72 9a be 04 00 00 00 e8 13 f2 84 00 4c 89 f7 b8 01 00 00 00 87 05 c5 2e c6 18 85 c0 0f 85 17 ff ff ff 90 <0f> 0b 90 48 81 ff 40 62 b6 8e 74 47 48 c7 c0 f0 28 54 90 48 c1 e8
RSP: 0018:ffffc90000a08d98 EFLAGS: 00010046
RAX: 0000000000000000 RBX: 0000000000000246 RCX: ffffffff81ac85ed
RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffffffff8eb66240
RBP: ffffc90000a08f18 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffffbfff34e5698 R12: 0000000000002904
R13: dffffc0000000000 R14: ffffffff8eb66240 R15: dffffc0000000000
FS: 00007f94af7c06c0(0000) GS:ffff888124eee000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00002000000bd038 CR3: 00000000580e6000 CR4: 00000000003526f0
DR0: 0000000040000005 DR1: 0000000100000000 DR2: 0000000000000898
DR3: 0000000000000006 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
rcu_core+0x3fe/0x1070 kernel/rcu/tree.c:2864
handle_softirqs+0x22a/0x870 kernel/softirq.c:626
__do_softirq kernel/softirq.c:660 [inline]
invoke_softirq kernel/softirq.c:496 [inline]
__irq_exit_rcu+0xca/0x220 kernel/softirq.c:739
irq_exit_rcu+0x9/0x30 kernel/softirq.c:756
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1061 [inline]
sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1061
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:csd_lock_wait kernel/smp.c:342 [inline]
RIP: 0010:smp_call_function_single+0x399/0x580 kernel/smp.c:687
Code: 33 44 89 f6 83 e6 01 31 ff e8 e3 fb 0b 00 41 83 e6 01 75 11 e8 98 f7 0b 00 4d 89 fe eb 3f e8 8e f7 0b 00 eb 3c 4d 89 fe f3 90 <43> 0f b6 04 2c 84 c0 75 0f f7 03 01 00 00 00 74 1d e8 71 f7 0b 00
RSP: 0018:ffffc90005a26ea0 EFLAGS: 00000246
RAX: ffffffff81baca2f RBX: ffffc90005a26ee8 RCX: 0000000000080000
RDX: ffffc90006652000 RSI: 000000000007ffff RDI: 0000000000080000
RBP: ffffc90005a26f78 R08: ffffffff9053f5f7 R09: 1ffffffff20a7ebe
R10: dffffc0000000000 R11: ffffffff8174f030 R12: 1ffff92000b44ddd
R13: dffffc0000000000 R14: 1ffff92000b44dd8 R15: 1ffff92000b44dd8
loaded_vmcs_clear arch/x86/kvm/vmx/vmx.c:836 [inline]
vmx_vcpu_load_vmcs+0xcd/0x5d0 arch/x86/kvm/vmx/vmx.c:1497
vmx_vcpu_load+0x1b0/0x260 arch/x86/kvm/vmx/vmx.c:1555
kvm_arch_vcpu_load+0x25d/0xa50 arch/x86/kvm/x86.c:5175
kvm_sched_in+0x7c/0xe0 virt/kvm/kvm_main.c:6399
__fire_sched_in_preempt_notifiers kernel/sched/core.c:4897 [inline]
fire_sched_in_preempt_notifiers kernel/sched/core.c:4903 [inline]
finish_task_switch+0xb14/0xbe0 kernel/sched/core.c:5216
context_switch kernel/sched/core.c:5352 [inline]
__schedule+0x166d/0x5590 kernel/sched/core.c:6961
preempt_schedule_common+0x82/0xd0 kernel/sched/core.c:7146
preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12
copy_shadow_to_vmcs12+0x4cf/0x5a0 arch/x86/kvm/vmx/nested.c:1652
nested_vmx_run+0x3d1/0xc30 arch/x86/kvm/vmx/nested.c:3813
__vmx_handle_exit arch/x86/kvm/vmx/vmx.c:6823 [inline]
vmx_handle_exit+0xfc4/0x16c0 arch/x86/kvm/vmx/vmx.c:6833
vcpu_enter_guest arch/x86/kvm/x86.c:11579 [inline]
vcpu_run+0x5dee/0x7990 arch/x86/kvm/x86.c:11736
kvm_arch_vcpu_ioctl_run+0x11e6/0x20d0 arch/x86/kvm/x86.c:12084
kvm_vcpu_ioctl+0xa62/0xfd0 virt/kvm/kvm_main.c:4479
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:597 [inline]
__se_sys_ioctl+0xfc/0x170 fs/ioctl.c:583
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f94ae99c799
Code: 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 01 48
RSP: 002b:00007f94af7c0028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f94aec15fa0 RCX: 00007f94ae99c799
RDX: 0000000000000000 RSI: 000000000000ae80 RDI: 0000000000000006
RBP: 00007f94aea32bd9 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f94aec16038 R14: 00007f94aec15fa0 R15: 00007ffcd18c3ef8
----------------
Code disassembly (best guess):
0: 33 44 89 f6 xor -0xa(%rcx,%rcx,4),%eax
4: 83 e6 01 and $0x1,%esi
7: 31 ff xor %edi,%edi
9: e8 e3 fb 0b 00 call 0xbfbf1
e: 41 83 e6 01 and $0x1,%r14d
12: 75 11 jne 0x25
14: e8 98 f7 0b 00 call 0xbf7b1
19: 4d 89 fe mov %r15,%r14
1c: eb 3f jmp 0x5d
1e: e8 8e f7 0b 00 call 0xbf7b1
23: eb 3c jmp 0x61
25: 4d 89 fe mov %r15,%r14
28: f3 90 pause
* 2a: 43 0f b6 04 2c movzbl (%r12,%r13,1),%eax <-- trapping instruction
2f: 84 c0 test %al,%al
31: 75 0f jne 0x42
33: f7 03 01 00 00 00 testl $0x1,(%rbx)
39: 74 1d je 0x58
3b: e8 71 f7 0b 00 call 0xbf7b1