WARNING in vcpu_enter_guest

From: syzbot
Date: Fri Nov 29 2019 - 03:20:12 EST


Hello,

syzbot found the following crash on:

HEAD commit: ad062195 Merge tag 'platform-drivers-x86-v5.4-1' of git://..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=154910ad600000
kernel config: https://syzkaller.appspot.com/x/.config?x=f9fc16a6374d5fd0
dashboard link: https://syzkaller.appspot.com/bug?extid=00be5da1d75f1cc95f6b
compiler: gcc (GCC) 9.0.0 20181231 (experimental)

Unfortunately, I don't have any reproducer for this crash yet.

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+00be5da1d75f1cc95f6b@xxxxxxxxxxxxxxxxxxxxxxxxx

WARNING: CPU: 1 PID: 15173 at arch/x86/kvm/x86.c:8007 vcpu_enter_guest+0x4b29/0x5e90 arch/x86/kvm/x86.c:8007
Kernel panic - not syncing: panic_on_warn set ...
CPU: 1 PID: 15173 Comm: syz-executor.5 Not tainted 5.3.0+ #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0x172/0x1f0 lib/dump_stack.c:113
panic+0x2dc/0x755 kernel/panic.c:219
__warn.cold+0x20/0x4c kernel/panic.c:576
report_bug+0x263/0x2b0 lib/bug.c:186
fixup_bug arch/x86/kernel/traps.c:179 [inline]
fixup_bug arch/x86/kernel/traps.c:174 [inline]
do_error_trap+0x11b/0x200 arch/x86/kernel/traps.c:272
do_invalid_op+0x37/0x50 arch/x86/kernel/traps.c:291
invalid_op+0x23/0x30 arch/x86/entry/entry_64.S:1028
RIP: 0010:vcpu_enter_guest+0x4b29/0x5e90 arch/x86/kvm/x86.c:8007
Code: 00 fc ff df 48 c1 ea 03 0f b6 04 02 84 c0 74 08 3c 03 0f 8e e9 11 00 00 41 83 a5 20 27 00 00 fb e9 5c bf ff ff e8 97 9e 65 00 <0f> 0b e9 98 be ff ff e8 8b 9e 65 00 31 ff be 07 00 00 00 e8 ef 97
RSP: 0018:ffff8880572bfa10 EFLAGS: 00010046
RAX: 0000000000040000 RBX: 0000000000000000 RCX: ffffc900109ce000
RDX: 0000000000040000 RSI: ffffffff810d3599 RDI: 0000000000000007
RBP: ffff8880572bfb20 R08: ffff8880576b62c0 R09: ffffed100aed6c59
R10: ffffed100aed6c58 R11: ffff8880576b62c7 R12: ffff88805fa9866c
R13: ffff88805fa98640 R14: 0000000000000001 R15: ffff88805fa98670
vcpu_run arch/x86/kvm/x86.c:8159 [inline]
kvm_arch_vcpu_ioctl_run+0x464/0x1750 arch/x86/kvm/x86.c:8367
kvm_vcpu_ioctl+0x4dc/0xfd0 arch/x86/kvm/../../../virt/kvm/kvm_main.c:2765
vfs_ioctl fs/ioctl.c:46 [inline]
file_ioctl fs/ioctl.c:509 [inline]
do_vfs_ioctl+0xdb6/0x13e0 fs/ioctl.c:696
ksys_ioctl+0xab/0xd0 fs/ioctl.c:713
__do_sys_ioctl fs/ioctl.c:720 [inline]
__se_sys_ioctl fs/ioctl.c:718 [inline]
__x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:718
do_syscall_64+0xfa/0x760 arch/x86/entry/common.c:290
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x4598e9
Code: fd b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 0f 83 cb b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f84f3c93c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00000000004598e9
RDX: 0000000000000000 RSI: 000000000000ae80 RDI: 0000000000000005
RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f84f3c946d4
R13: 00000000004c2c68 R14: 00000000004d6330 R15: 00000000ffffffff
Kernel Offset: disabled
Rebooting in 86400 seconds..


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