Bug 216598

Summary:	Assertion Failure in kvm selftest mmio_warning_test
Product:	Virtualization	Reporter:	Yang Lixiao (lixiao.yang)
Component:	kvm	Assignee:	virtualization_kvm
Status:	NEW ---
Severity:	normal	CC:	gordon.jin, xudong.hao
Priority:	P1
Hardware:	Intel
OS:	Linux
Kernel Version:	6.0.0-rc7	Subsystem:
Regression:	Yes	Bisected commit-id:
Attachments:	Host dmesg log

Description Yang Lixiao 2022-10-17 07:42:19 UTC

Created attachment 303018 [details]
Host dmesg log

Environment:
CPU Architecture: x86_64
Host OS: Red Hat Enterprise Linux 8.4 (Ootpa)
Host kernel: 6.0.0-rc7
gcc: gcc (GCC) 8.4.1 
Host kernel source:  https://git.kernel.org/pub/scm/virt/kvm/kvm.git
Branch: next
Commit: e18d6152ff0f41b7f01f9817372022df04e0d354


Bug Detailed Description:
Assertion failure and host call trace happened after executing kvm selftest mmio_warning_test.


Reproducing Steps:
git clone https://git.kernel.org/pub/scm/virt/kvm/kvm.git
cd kvm && make headers_install
cd kvm/tools/testing/selftests/kvm && make
cd x86_64 && ./mmio_warning_test

Actual Result:
[root@icx-2s2 ~]# kvm/tools/testing/selftests/kvm/x86_64/mmio_warning_test
ret1=0 exit_reason=17 suberror=1
ret1=0 exit_reason=8 suberror=65530
ret1=0 exit_reason=17 suberror=1
ret1=0 exit_reason=8 suberror=65530
ret1=0 exit_reason=17 suberror=1
ret1=0 exit_reason=8 suberror=65530
ret1=0 exit_reason=17 suberror=1
ret1=0 exit_reason=8 suberror=65530
ret1=0 exit_reason=17 suberror=1
ret1=0 exit_reason=8 suberror=65530
ret1=0 exit_reason=17 suberror=1
ret1=0 exit_reason=8 suberror=65530
ret1=0 exit_reason=17 suberror=1
ret1=0 exit_reason=8 suberror=65530
ret1=0 exit_reason=17 suberror=1
ret1=0 exit_reason=8 suberror=65530
ret1=0 exit_reason=17 suberror=1
ret1=0 exit_reason=8 suberror=65530
ret1=0 exit_reason=17 suberror=1
ret1=0 exit_reason=8 suberror=65530
==== Test Assertion Failure ====
  x86_64/mmio_warning_test.c:118: warnings_before == warnings_after
  pid=4383 tid=4383 errno=0 - Success
     1  0x0000000000402463: main at mmio_warning_test.c:117
     2  0x00007f5bc5c23492: ?? ??:0
     3  0x00000000004024dd: _start at ??:?
  Warnings found in kernel.  Run 'dmesg' to inspect them.

[root@icx-2s2 ~]#dmesg |grep -i "call trace"
[  208.938961] Call Trace:
[  209.289307] Call Trace:
[  209.683239] Call Trace:
[  210.016660] Call Trace:
[  210.389796] Call Trace:
[  210.727731] Call Trace:
[  211.090710] Call Trace:
[  211.422556] Call Trace:
[  211.785661] Call Trace:
[  212.117551] Call Trace:

Expected Result:
[root@icx-2s2 ~]#kvm/tools/testing/selftests/kvm/x86_64/mmio_warning_test
[root@icx-2s2 ~]
[root@icx-2s2 ~]#dmesg |grep -i "call trace"
[root@icx-2s2 ~]

Comment 1 Sean Christopherson 2022-10-17 15:23:02 UTC

On Mon, Oct 17, 2022, bugzilla-daemon@kernel.org wrote:
> Created attachment 303018 [details]
>   --> https://bugzilla.kernel.org/attachment.cgi?id=303018&action=edit
> ==== Test Assertion Failure ====
>   x86_64/mmio_warning_test.c:118: warnings_before == warnings_after
>   pid=4383 tid=4383 errno=0 - Success
>      1  0x0000000000402463: main at mmio_warning_test.c:117
>      2  0x00007f5bc5c23492: ?? ??:0
>      3  0x00000000004024dd: _start at ??:?
>   Warnings found in kernel.  Run 'dmesg' to inspect them.

Known bug.  Fix is posted[*], will make sure it gets into 6.1 and I suppose
backported to stable.

[*] https://lore.kernel.org/all/20220930230008.1636044-1-seanjc@google.com