WARNING in nested_vmx_vmexit

Status: premoderation: reported C repro on 2025/10/22 16:54
Bug presence: origin:lts
[Documentation on labels]
Reported-by: syzbot+7a39174c3456b1b1a948@syzkaller.appspotmail.com
First crash: 378d, last: 11d
▶ ▼ Bug presence (2)
Date Name Commit Repro Result
2025/10/23 lts (merge base) b0c51e95f54e C [report] WARNING in nested_vmx_vmexit
2025/10/23 upstream (ToT) 43e9ad0c55a3 C Didn't crash
▶ ▼ Similar bugs (3)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.1 WARNING in nested_vmx_vmexit -1 syz, C 9 2d08h 18d 0/3 upstream: reported C repro on 2026/10/18 07:56
upstream WARNING in nested_vmx_vmexit kvm-x86 -1 syz, C done 101 1779d 1796d 20/29 fixed on 2022/03/08 16:11
linux-5.15 WARNING in nested_vmx_vmexit -1 3 15d 16d 0/3 upstream: reported on 2026/10/20 10:12
▶ ▼ Last patch testing requests (9)
Created Duration User Patch Repo Result
2026/10/11 07:48 17m retest repro android16-6.12 report job log log
2026/09/01 21:22 8m retest repro android16-6.12 report job log log
2026/07/26 04:45 16m retest repro android16-6.12 log
2026/06/07 05:44 16m retest repro android16-6.12 log
2026/05/16 04:46 16m retest repro android16-6.12 log
2026/03/27 00:27 41m retest repro android16-6.12 report log
2026/02/17 06:32 15m retest repro android16-6.12 report log
2026/01/15 06:05 4m retest repro android16-6.12 error
2025/11/05 23:14 9m retest repro android16-6.12 error

Sample crash report:
------------[ cut here ]------------
WARNING: CPU: 0 PID: 312 at arch/x86/kvm/vmx/nested.c:5014 nested_vmx_vmexit+0x289d/0x28f0 arch/x86/kvm/vmx/nested.c:5013
Modules linked in:
CPU: 0 UID: 0 PID: 312 Comm: syz-executor241 Not tainted syzkaller #0 790d506eeb1243e613a7e15525cb861d28cb7486
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/07/2026
RIP: 0010:nested_vmx_vmexit+0x289d/0x28f0 arch/x86/kvm/vmx/nested.c:5013
Code: 3c 57 00 e9 38 f0 ff ff e8 00 3c 57 00 bf 00 44 00 00 e8 c6 a5 fa ff eb 11 e8 ef 3b 57 00 e8 ba 3a 76 04 eb 05 e8 e3 3b 57 00 <0f> 0b 49 bc 00 00 00 00 00 fc ff df 4c 8b 6c 24 28 4c 8b 7c 24 20
RSP: 0018:ffffc9000126f7e0 EFLAGS: 00010293
RAX: ffffffff8132131d RBX: 0000000000000000 RCX: ffff88812ca8e2c0
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000007
RBP: ffffc9000126f940 R08: ffff8881077121bf R09: 1ffff11020ee2437
R10: dffffc0000000000 R11: ffffed1020ee2438 R12: dffffc0000000000
R13: 1ffff9200024df10 R14: ffff88810526a2ef R15: ffff888107712180
FS:  0000000000000000(0000) GS:ffff8881f6c00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f8bc63f6270 CR3: 0000000105fce000 CR4: 00000000003526b0
Call Trace:
 <TASK>
 vmx_leave_nested arch/x86/kvm/vmx/nested.c:6753 [inline]
 nested_vmx_free_vcpu+0x8f/0xe0 arch/x86/kvm/vmx/nested.c:377
 vmx_vcpu_free+0x10d/0x2c0 arch/x86/kvm/vmx/vmx.c:7509
 kvm_arch_vcpu_destroy+0x5a/0x1e0 arch/x86/kvm/x86.c:12489
 kvm_vcpu_destroy virt/kvm/kvm_main.c:508 [inline]
 kvm_destroy_vcpus+0xe1/0x250 virt/kvm/kvm_main.c:528
 kvm_arch_destroy_vm+0x226/0x410 arch/x86/kvm/x86.c:13001
 kvm_destroy_vm virt/kvm/kvm_main.c:1355 [inline]
 kvm_put_kvm+0xadf/0x12d0 virt/kvm/kvm_main.c:1392
 kvm_vm_release+0x47/0x70 virt/kvm/kvm_main.c:1415
 __fput+0x208/0xa30 fs/file_table.c:447
 ____fput+0x20/0x30 fs/file_table.c:475
 task_work_run+0x1e8/0x260 kernel/task_work.c:246
 exit_task_work include/linux/task_work.h:43 [inline]
 do_exit+0xa46/0x2850 kernel/exit.c:961
 do_group_exit+0x21f/0x2f0 kernel/exit.c:1104
 __do_sys_exit_group kernel/exit.c:1115 [inline]
 __se_sys_exit_group kernel/exit.c:1113 [inline]
 __x64_sys_exit_group+0x43/0x50 kernel/exit.c:1113
 x64_sys_call+0x2ed2/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:232
 do_syscall_x64 arch/x86/entry/common.c:47 [inline]
 do_syscall_64+0x57/0xf0 arch/x86/entry/common.c:78
 entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7f8bc6356185
Code: Unable to access opcode bytes at 0x7f8bc635615b.
RSP: 002b:00007ffd29314b28 EFLAGS: 00000206 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 00007f8bc6356185
RDX: 00000000000000e7 RSI: ffffffffffffffd8 RDI: 0000000000000000

Crashes (3):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/10/24 18:12 android16-6.12 32521e28daaa 1d9ca40b .config strace log report syz / log C [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust WARNING in nested_vmx_vmexit
2026/02/03 01:42 android16-6.12 12691bc9c3f1 d78927dd .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust WARNING in nested_vmx_vmexit
2025/10/22 16:53 android16-6.12 0d6730ee6542 252fbbad .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust WARNING in nested_vmx_vmexit
* Struck through repros no longer work on HEAD.