[syzbot] WARNING in x86_emulate_instruction

[syzbot] WARNING in x86_emulate_instruction

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit:    8ac91e6c Merge tag 'for-5.13-rc2-tag' of git://git.kernel...
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=16a80fc7d00000
kernel config:  https://syzkaller.appspot.com/x/.config?x=dddb87edd6431081
dashboard link: https://syzkaller.appspot.com/bug?extid=71271244f206d17f6441
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=12d1f89bd00000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=134683fdd00000

The issue was bisected to:

commit 9a7832ce3d920426a36cdd78eda4b3568d4d09e3
Author: Steve Wahl <steve.wahl@hpe.com>
Date:   Fri Jan 8 15:35:49 2021 +0000

    perf/x86/intel/uncore: With > 8 nodes, get pci bus die id from NUMA info

bisection log:  https://syzkaller.appspot.com/x/bisect.txt?x=152bf9b3d00000
final oops:     https://syzkaller.appspot.com/x/report.txt?x=172bf9b3d00000
console output: https://syzkaller.appspot.com/x/log.txt?x=132bf9b3d00000

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+71271244f206d17f6441@syzkaller.appspotmail.com
Fixes: 9a7832ce3d92 ("perf/x86/intel/uncore: With > 8 nodes, get pci bus die id from NUMA info")

L1TF CPU bug present and SMT on, data leak possible. See CVE-2018-3646 and https://www.kernel.org/doc/html/latest/admin-guide/hw-vuln/l1tf.html for details.
------------[ cut here ]------------
WARNING: CPU: 0 PID: 8431 at arch/x86/kvm/x86.c:7620 x86_emulate_instruction+0x9e8/0x1460 arch/x86/kvm/x86.c:7620
Modules linked in:
CPU: 0 PID: 8431 Comm: syz-executor681 Not tainted 5.13.0-rc2-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:x86_emulate_instruction+0x9e8/0x1460 arch/x86/kvm/x86.c:7620
Code: c0 74 07 7f 05 e8 a8 48 a9 00 41 0f b6 5c 24 30 bf 06 00 00 00 89 de e8 56 4d 64 00 80 fb 06 0f 85 06 05 00 00 e8 98 46 64 00 <0f> 0b e8 91 46 64 00 48 89 ef e8 89 48 fe ff c7 44 24 1c 01 00 00
RSP: 0018:ffffc90002057930 EFLAGS: 00010293
RAX: 0000000000000000 RBX: 0000000000000006 RCX: 0000000000000000
RDX: ffff88802caad4c0 RSI: ffffffff81108cc8 RDI: 0000000000000003
RBP: ffff88802eb08000 R08: 0000000000000000 R09: 0000000000000006
R10: ffffffff81108cba R11: 0000000000000006 R12: ffff88802bd48000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000040
FS:  00000000012e3300(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 000000001459c000 CR4: 00000000001526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 kvm_mmu_page_fault+0x2eb/0x1890 arch/x86/kvm/mmu/mmu.c:5103
 handle_ept_violation+0x29c/0x6f0 arch/x86/kvm/vmx/vmx.c:5402
 __vmx_handle_exit arch/x86/kvm/vmx/vmx.c:6106 [inline]
 vmx_handle_exit+0x336/0x1800 arch/x86/kvm/vmx/vmx.c:6123
 vcpu_enter_guest+0x235e/0x47e0 arch/x86/kvm/x86.c:9425
 vcpu_run arch/x86/kvm/x86.c:9491 [inline]
 kvm_arch_vcpu_ioctl_run+0x47d/0x1990 arch/x86/kvm/x86.c:9719
 kvm_vcpu_ioctl+0x467/0xd10 arch/x86/kvm/../../../virt/kvm/kvm_main.c:3458
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:1069 [inline]
 __se_sys_ioctl fs/ioctl.c:1055 [inline]
 __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:1055
 do_syscall_64+0x3a/0xb0 arch/x86/entry/common.c:47
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x440da9
Code: 28 c3 e8 2a 14 00 00 66 2e 0f 1f 84 00 00 00 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 c0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffe2af5d538 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000400488 RCX: 0000000000440da9
RDX: 0000000000000000 RSI: 000000000000ae80 RDI: 0000000000000005
RBP: 00000000004048a0 R08: 0000000000400488 R09: 0000000000400488
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000404930
R13: 0000000000000000 R14: 00000000004ae018 R15: 0000000000400488


---
This report is generated by a bot. It may contain errors.
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syzbot will keep track of this issue. See:
https://goo.gl/tpsmEJ#status for how to communicate with syzbot.
For information about bisection process see: https://goo.gl/tpsmEJ#bisection
syzbot can test patches for this issue, for details see:
https://goo.gl/tpsmEJ#testing-patches

Re: [syzbot] WARNING in x86_emulate_instruction

[Thomas Gleixner]

On Fri, May 21 2021 at 19:52, syzbot wrote:

> Hello,
>
> syzbot found the following issue on:
>
> HEAD commit:    8ac91e6c Merge tag 'for-5.13-rc2-tag' of git://git.kernel...
> git tree:       upstream
> console output: https://syzkaller.appspot.com/x/log.txt?x=16a80fc7d00000
> kernel config:  https://syzkaller.appspot.com/x/.config?x=dddb87edd6431081
> dashboard link: https://syzkaller.appspot.com/bug?extid=71271244f206d17f6441
> syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=12d1f89bd00000
> C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=134683fdd00000
>
> The issue was bisected to:
>
> commit 9a7832ce3d920426a36cdd78eda4b3568d4d09e3
> Author: Steve Wahl <steve.wahl@hpe.com>
> Date:   Fri Jan 8 15:35:49 2021 +0000
>
>     perf/x86/intel/uncore: With > 8 nodes, get pci bus die id from NUMA info
>
> bisection log:  https://syzkaller.appspot.com/x/bisect.txt?x=152bf9b3d00000
> final oops:     https://syzkaller.appspot.com/x/report.txt?x=172bf9b3d00000
> console output: https://syzkaller.appspot.com/x/log.txt?x=132bf9b3d00000
>
> IMPORTANT: if you fix the issue, please add the following tag to the commit:
> Reported-by: syzbot+71271244f206d17f6441@syzkaller.appspotmail.com
> Fixes: 9a7832ce3d92 ("perf/x86/intel/uncore: With > 8 nodes, get pci bus die id from NUMA info")

So this is stale for a week now. It's fully reproducible and nobody
can't be bothered to look at that?

What's wrong with you people?

Thanks,

        tglx

Re: [syzbot] WARNING in x86_emulate_instruction

[Paolo Bonzini]

On 28/05/21 00:52, Thomas Gleixner wrote:
> 
> So this is stale for a week now. It's fully reproducible and nobody
> can't be bothered to look at that?
> 
> What's wrong with you people?

Actually there's a patch on list ("KVM: X86: Fix warning caused by stale 
emulation context").  Take care.

Paolo

Re: [syzbot] WARNING in x86_emulate_instruction

[Thomas Gleixner]

On Fri, May 28 2021 at 01:21, Paolo Bonzini wrote:
> On 28/05/21 00:52, Thomas Gleixner wrote:
>> 
>> So this is stale for a week now. It's fully reproducible and nobody
>> can't be bothered to look at that?
>> 
>> What's wrong with you people?
>
> Actually there's a patch on list ("KVM: X86: Fix warning caused by stale 
> emulation context").  Take care.

That's useful, but does not change the fact that nobody bothered to
reply to this report ...

Re: [syzbot] WARNING in x86_emulate_instruction

[Wanpeng Li]

On Fri, 28 May 2021 at 08:31, Thomas Gleixner <tglx@linutronix.de> wrote:
>
> On Fri, May 28 2021 at 01:21, Paolo Bonzini wrote:
> > On 28/05/21 00:52, Thomas Gleixner wrote:
> >>
> >> So this is stale for a week now. It's fully reproducible and nobody
> >> can't be bothered to look at that?
> >>
> >> What's wrong with you people?
> >
> > Actually there's a patch on list ("KVM: X86: Fix warning caused by stale
> > emulation context").  Take care.
>
> That's useful, but does not change the fact that nobody bothered to
> reply to this report ...

Will do it next time. Have a nice evening, guys!

Re: [syzbot] WARNING in x86_emulate_instruction

[Dmitry Vyukov]

On Fri, May 28, 2021 at 2:34 AM Wanpeng Li <kernellwp@gmail.com> wrote:
>
> On Fri, 28 May 2021 at 08:31, Thomas Gleixner <tglx@linutronix.de> wrote:
> >
> > On Fri, May 28 2021 at 01:21, Paolo Bonzini wrote:
> > > On 28/05/21 00:52, Thomas Gleixner wrote:
> > >>
> > >> So this is stale for a week now. It's fully reproducible and nobody
> > >> can't be bothered to look at that?
> > >>
> > >> What's wrong with you people?
> > >
> > > Actually there's a patch on list ("KVM: X86: Fix warning caused by stale
> > > emulation context").  Take care.
> >
> > That's useful, but does not change the fact that nobody bothered to
> > reply to this report ...
>
> Will do it next time. Have a nice evening, guys!

There was an idea to do this automatically by syzbot:

dashboard/app: notify bug report about fix patches
https://github.com/google/syzkaller/issues/1574

Namely: if syzbot discovers a fix anywhere (by the hash), it could
send a notification email to the bug report email thread.
The downside is that the robot sends even more emails, so I am not
sure how it will be accepted. Any opinions?

Re: [syzbot] WARNING in x86_emulate_instruction

[Paolo Bonzini]

On 07/06/21 12:34, Dmitry Vyukov wrote:
> On Fri, May 28, 2021 at 2:34 AM Wanpeng Li <kernellwp@gmail.com> wrote:
>>
>> On Fri, 28 May 2021 at 08:31, Thomas Gleixner <tglx@linutronix.de> wrote:
>>>
>>> On Fri, May 28 2021 at 01:21, Paolo Bonzini wrote:
>>>> On 28/05/21 00:52, Thomas Gleixner wrote:
>>>>>
>>>>> So this is stale for a week now. It's fully reproducible and nobody
>>>>> can't be bothered to look at that?
>>>>>
>>>>> What's wrong with you people?
>>>>
>>>> Actually there's a patch on list ("KVM: X86: Fix warning caused by stale
>>>> emulation context").  Take care.
>>>
>>> That's useful, but does not change the fact that nobody bothered to
>>> reply to this report ...
>>
>> Will do it next time. Have a nice evening, guys!
> 
> There was an idea to do this automatically by syzbot:
> 
> dashboard/app: notify bug report about fix patches
> https://github.com/google/syzkaller/issues/1574
> 
> Namely: if syzbot discovers a fix anywhere (by the hash), it could
> send a notification email to the bug report email thread.
> The downside is that the robot sends even more emails, so I am not
> sure how it will be accepted. Any opinions?

I would like it.  Usually somebody replies _before_ they start working 
on it, but sometimes they send a patch right away.

Paolo