WARNING in x86_emulate_insn

Status: closed as invalid on 2019/11/07 10:18
Subsystems: kvm-x86
[Documentation on labels]
Reported-by: syzbot+75375385991b4f8c599704a10849863c586ea284@syzkaller.appspotmail.com
First crash: 3155d, last: 3106d
Fix bisection: failed (error log, bisect log)
  
▶ ▼ Similar bugs (2)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream WARNING in x86_emulate_insn (2) prio:high kvm-x86 -1 C 3 44d 241d 0/29 upstream: reported C repro on 2025/11/24 14:40
android-6-12 WARNING in x86_emulate_insn origin:upstream -1 syz 1 128d 142d 0/1 premoderation: reported syz repro on 2026/03/03 07:34

Sample crash report:
kvm: KVM_SET_TSS_ADDR need to be called before entering vcpu
WARNING: CPU: 0 PID: 3153 at arch/x86/kvm/emulate.c:5654 x86_emulate_insn+0xd01/0x3cf0 arch/x86/kvm/emulate.c:5654
Kernel panic - not syncing: panic_on_warn set ...

CPU: 0 PID: 3153 Comm: syzkaller990902 Not tainted 4.15.0-rc2+ #212
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x194/0x257 lib/dump_stack.c:53
 panic+0x1e4/0x41c kernel/panic.c:183
 __warn+0x1dc/0x200 kernel/panic.c:547
 report_bug+0x211/0x2d0 lib/bug.c:184
 fixup_bug.part.11+0x37/0x80 arch/x86/kernel/traps.c:177
 fixup_bug arch/x86/kernel/traps.c:246 [inline]
 do_error_trap+0x2d7/0x3e0 arch/x86/kernel/traps.c:295
 do_invalid_op+0x1b/0x20 arch/x86/kernel/traps.c:314
 invalid_op+0x18/0x20 arch/x86/entry/entry_64.S:930
RIP: 0010:x86_emulate_insn+0xd01/0x3cf0 arch/x86/kvm/emulate.c:5654
RSP: 0018:ffff8801c56f7300 EFLAGS: 00010293
RAX: ffff8801c62d2080 RBX: 1ffff10038adee69 RCX: ffffffff81154231
RDX: 0000000000000000 RSI: ffffffffffffffff RDI: ffff8801c55da888
RBP: ffff8801c56f7410 R08: ffff8801c55d8040 R09: ffffffff85224dc0
R10: 0000000000000002 R11: ffffed0038abb551 R12: 00000000000000ff
R13: ffff8801c55da860 R14: 0000000000000002 R15: ffff8801c55da983
 x86_emulate_instruction+0x411/0x1ad0 arch/x86/kvm/x86.c:5769
 emulate_instruction arch/x86/include/asm/kvm_host.h:1164 [inline]
 handle_invalid_guest_state arch/x86/kvm/vmx.c:6606 [inline]
 vmx_handle_exit+0x6e3/0x1ce0 arch/x86/kvm/vmx.c:8826
 vcpu_enter_guest arch/x86/kvm/x86.c:7082 [inline]
 vcpu_run arch/x86/kvm/x86.c:7144 [inline]
 kvm_arch_vcpu_ioctl_run+0x1cb4/0x5c60 arch/x86/kvm/x86.c:7312
 kvm_vcpu_ioctl+0x64c/0x1010 arch/x86/kvm/../../../virt/kvm/kvm_main.c:2574
 vfs_ioctl fs/ioctl.c:46 [inline]
 do_vfs_ioctl+0x1b1/0x1530 fs/ioctl.c:686
 SYSC_ioctl fs/ioctl.c:701 [inline]
 SyS_ioctl+0x8f/0xc0 fs/ioctl.c:692
 entry_SYSCALL_64_fastpath+0x1f/0x96
RIP: 0033:0x4402e9
RSP: 002b:00007ffde2bdf2c8 EFLAGS: 00000217 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: ffffffffffffffff RCX: 00000000004402e9
RDX: 0000000000000000 RSI: 000000000000ae80 RDI: 0000000000000005
RBP: 00000000006ca018 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000217 R12: 0000000000401c50
R13: 0000000000401ce0 R14: 0000000000000000 R15: 0000000000000000
Dumping ftrace buffer:
   (ftrace buffer empty)
Kernel Offset: disabled
Rebooting in 86400 seconds..

Crashes (309):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2017/12/08 03:21 upstream 968edbd93c0c 5d643f8e .config console log report syz C ci-upstream-kasan-gce
2017/12/11 01:07 mmots 82bcf1def3b5 5ad0ce95 .config console log report syz C ci-upstream-mmots-kasan-gce
2017/12/05 03:31 upstream 2391f0b4808e de212f1a .config console log report syz ci-upstream-kasan-gce-386
2017/12/02 15:37 upstream 2db767d9889c 48359b97 .config console log report syz ci-upstream-kasan-gce-386
2017/12/08 09:41 mmots 82bcf1def3b5 5d643f8e .config console log report syz ci-upstream-mmots-kasan-gce
2017/12/02 14:28 linux-next fb20eb9d798d 16668351 .config console log report syz ci-upstream-next-kasan-gce
2018/01/20 13:25 upstream 8dd903d2cf7b fbbdcd92 .config console log report ci-upstream-kasan-gce
2018/01/20 12:16 upstream 8dd903d2cf7b fbbdcd92 .config console log report ci-upstream-kasan-gce
2018/01/20 11:34 upstream 8dd903d2cf7b fbbdcd92 .config console log report ci-upstream-kasan-gce
2018/01/20 06:34 upstream ec835f8104a2 fbbdcd92 .config console log report ci-upstream-kasan-gce
2018/01/19 22:18 upstream ec835f8104a2 fbbdcd92 .config console log report ci-upstream-kasan-gce
2018/01/19 17:40 upstream dda3e15231b3 161c1d64 .config console log report ci-upstream-kasan-gce
2018/01/19 15:56 upstream dda3e15231b3 161c1d64 .config console log report ci-upstream-kasan-gce
2018/01/19 13:10 upstream dda3e15231b3 161c1d64 .config console log report ci-upstream-kasan-gce
2018/01/19 12:42 upstream dda3e15231b3 161c1d64 .config console log report ci-upstream-kasan-gce
2018/01/19 07:08 upstream dda3e15231b3 161c1d64 .config console log report ci-upstream-kasan-gce
2018/01/19 01:37 upstream dda3e15231b3 161c1d64 .config console log report ci-upstream-kasan-gce
2018/01/18 21:47 upstream dda3e15231b3 161c1d64 .config console log report ci-upstream-kasan-gce
2018/01/18 17:04 upstream 1d966eb4d632 56cc113a .config console log report ci-upstream-kasan-gce
2018/01/18 06:37 upstream 88dc7fca1800 b8970f31 .config console log report ci-upstream-kasan-gce
2018/01/18 05:50 upstream 88dc7fca1800 b8970f31 .config console log report ci-upstream-kasan-gce
2018/01/18 01:50 upstream 88dc7fca1800 b8970f31 .config console log report ci-upstream-kasan-gce
2018/01/18 01:36 upstream 88dc7fca1800 b8970f31 .config console log report ci-upstream-kasan-gce
2018/01/17 22:39 upstream 88dc7fca1800 b8970f31 .config console log report ci-upstream-kasan-gce
2018/01/17 18:29 upstream 8cbab92dff77 a46e5318 .config console log report ci-upstream-kasan-gce
2018/01/17 18:22 upstream 8cbab92dff77 a46e5318 .config console log report ci-upstream-kasan-gce
2018/01/17 18:18 upstream 8cbab92dff77 a46e5318 .config console log report ci-upstream-kasan-gce
2018/01/17 10:28 upstream 8cbab92dff77 a46e5318 .config console log report ci-upstream-kasan-gce
2018/01/17 07:55 upstream 41aa5e5d712b a46e5318 .config console log report ci-upstream-kasan-gce
2018/01/16 22:39 upstream 41aa5e5d712b a46e5318 .config console log report ci-upstream-kasan-gce
2018/01/16 21:37 upstream 41aa5e5d712b a46e5318 .config console log report ci-upstream-kasan-gce
2018/01/16 21:20 upstream 41aa5e5d712b a46e5318 .config console log report ci-upstream-kasan-gce
2018/01/16 20:28 upstream a8750ddca918 a46e5318 .config console log report ci-upstream-kasan-gce
2018/01/16 18:56 upstream a8750ddca918 4198e588 .config console log report ci-upstream-kasan-gce
2018/01/16 08:46 upstream a8750ddca918 4198e588 .config console log report ci-upstream-kasan-gce
2018/01/16 06:58 upstream a8750ddca918 e17f4a5d .config console log report ci-upstream-kasan-gce
2018/01/15 21:01 upstream a8750ddca918 e17f4a5d .config console log report ci-upstream-kasan-gce
2018/01/15 09:55 upstream a8750ddca918 66d492a6 .config console log report ci-upstream-kasan-gce
2018/01/20 08:27 upstream ec835f8104a2 fbbdcd92 .config console log report ci-upstream-kasan-gce-386
2018/01/19 05:18 upstream dda3e15231b3 161c1d64 .config console log report ci-upstream-kasan-gce-386
2018/01/17 08:24 upstream 41aa5e5d712b a46e5318 .config console log report ci-upstream-kasan-gce-386
2018/01/17 07:26 upstream 41aa5e5d712b a46e5318 .config console log report ci-upstream-kasan-gce-386
2018/01/16 16:42 upstream a8750ddca918 4198e588 .config console log report ci-upstream-kasan-gce-386
2018/01/16 09:38 upstream a8750ddca918 4198e588 .config console log report ci-upstream-kasan-gce-386
2018/01/16 00:16 upstream a8750ddca918 e17f4a5d .config console log report ci-upstream-kasan-gce-386
2018/01/19 00:42 mmots ce3c209f6733 161c1d64 .config console log report ci-upstream-mmots-kasan-gce
* Struck through repros no longer work on HEAD.