Bug 216098

Summary:	Assertion Failure in kvm selftest mmu_role_test
Product:	Virtualization	Reporter:	Yang Lixiao (lixiao.yang)
Component:	kvm	Assignee:	virtualization_kvm
Status:	NEW ---
Severity:	normal	CC:	gordon.jin, seanjc
Priority:	P1
Hardware:	Intel
OS:	Linux
URL:	https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
Kernel Version:	5.18	Subsystem:
Regression:	No	Bisected commit-id:
Attachments:	The kernel config file I used to build kernel

Description Yang Lixiao 2022-06-09 06:11:08 UTC

Created attachment 301133 [details]
The kernel config file I used to build kernel

Environment:
CPU Architecture: x86_64
Host OS: Red Hat Enterprise Linux 8.4 (Ootpa)
Host kernel: Linux 5.18 release 
gcc: gcc (GCC) 8.3.1 
Host kernel source: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
Branch: master
Commit: 4b0986a3613c92f4ec1bdc7f60ec66fea135991f
Tag: v5.18

Bug Detailed Description:
Assertion failure happened after executing kvm selftest mmu_role_test with argument -g or -m.


Reproducing Steps:
git clone https://git.kernel.org/pub/scm/virt/kvm/kvm.git
cd kvm/tools/testing/selftests/kvm && make
cd x86_64 && ./mmu_role_test -g
./mmu_role_test -m

Actual Result:
[root@icx-2s2 ~]# /usr/local/bin/mmu_role_test -g
Test MMIO after toggling CPUID.GBPAGES
==== Test Assertion Failure ====
  lib/x86_64/processor.c:898: rc == 0
  pid=189748 tid=189748 errno=22 - Invalid argument
     1  0x000000000040b66a: vcpu_set_cpuid at processor.c:897
     2  0x00000000004026df: mmu_role_test at mmu_role_test.c:60
     3  0x00000000004024a2: main at mmu_role_test.c:137
     4  0x00007f73b16237b2: ?? ??:0
     5  0x00000000004024ed: _start at ??:?
  KVM_SET_CPUID2 failed, rc: -1 errno: 22

[root@icx-2s2 ~]# /usr/local/bin/mmu_role_test -m
Test MMIO after changing CPUID.MAXPHYADDR
==== Test Assertion Failure ====
  lib/x86_64/processor.c:898: rc == 0
  pid=189759 tid=189759 errno=22 - Invalid argument
     1  0x000000000040b66a: vcpu_set_cpuid at processor.c:897
     2  0x00000000004026df: mmu_role_test at mmu_role_test.c:60
     3  0x0000000000402479: main at mmu_role_test.c:143
     4  0x00007f318f8237b2: ?? ??:0
     5  0x00000000004024ed: _start at ??:?
  KVM_SET_CPUID2 failed, rc: -1 errno: 22

Expected result:
[root@icx-2s2 ~]# /usr/local/bin/mmu_role_test -g
[root@icx-2s2 ~]# /usr/local/bin/mmu_role_test -m
[root@icx-2s2 ~]#

Comment 1 Yang Lixiao 2022-06-09 06:25:07 UTC

(In reply to Yang Lixiao from comment #0)
Correction:
Actual Result:
[root@icx-2s2 ~]# kvm/tools/testing/selftests/kvm/mmu_role_test -g
Test MMIO after toggling CPUID.GBPAGES
==== Test Assertion Failure ====
  lib/x86_64/processor.c:898: rc == 0
  pid=189748 tid=189748 errno=22 - Invalid argument
     1  0x000000000040b66a: vcpu_set_cpuid at processor.c:897
     2  0x00000000004026df: mmu_role_test at mmu_role_test.c:60
     3  0x00000000004024a2: main at mmu_role_test.c:137
     4  0x00007f73b16237b2: ?? ??:0
     5  0x00000000004024ed: _start at ??:?
  KVM_SET_CPUID2 failed, rc: -1 errno: 22

[root@icx-2s2 ~]#kvm/tools/testing/selftests/kvm/mmu_role_test -m
Test MMIO after changing CPUID.MAXPHYADDR
==== Test Assertion Failure ====
  lib/x86_64/processor.c:898: rc == 0
  pid=189759 tid=189759 errno=22 - Invalid argument
     1  0x000000000040b66a: vcpu_set_cpuid at processor.c:897
     2  0x00000000004026df: mmu_role_test at mmu_role_test.c:60
     3  0x0000000000402479: main at mmu_role_test.c:143
     4  0x00007f318f8237b2: ?? ??:0
     5  0x00000000004024ed: _start at ??:?
  KVM_SET_CPUID2 failed, rc: -1 errno: 22

Comment 2 Sean Christopherson 2022-06-09 16:08:48 UTC

This test was made obsolete by disallowing CPUID changes after KVM_RUN.

https://lore.kernel.org/all/20220604012058.1972195-14-seanjc@google.com