instruction intercept test in vmx from ubuntu_kvm_unit_tests failed with KVM instances (Unhandled exception 13 #GP at ip 0000000000403f55)

[Po-Hsu Lin]

Issue found in 5.11.0-1009.9+21.10.1-kvm
This is not a regression since the test was run with the latest hirsute-WIP branch, with upstream tip c986dbe867053 ("x86/vmx: skip error-code delivery tests for #CP").

This is a sub test in vmx:
filter = -exit_monitor_from_l2_test, test = instruction intercept

 Test suite: instruction intercept
 PASS: execute HLT
 PASS: intercept HLT
 PASS: execute INVLPG
 PASS: intercept INVLPG
 Feature required for MWAIT is not supported.
 Unhandled exception 13 #GP at ip 0000000000403f55
 error_code=0000 rflags=00010046 cs=00000008
 rax=0000000000403f53 rcx=0000000000000000 rdx=0000000000000000 rbx=00000000004367d6
 rbp=000000000100efdf rsi=0000000000000000 rdi=0000000000000006
 r8=000000000100e7c5 r9=00000000000003f8 r10=000000000000000d r11=0000000000000000
 r12=0000000000000000 r13=0000000000000000 r14=0000000000000000 r15=0000000000000000
 cr0=0000000080010031 cr2=ffffffffffffc000 cr3=0000000001007000 cr4=0000000000002020
 cr8=0000000000000000
 STACK: @403f55 401064 400549

This failure will prevent the vmx test to proceed.

[Po-Hsu Lin (cypressyew)]

Can be found on 5.8.0-1029.31 KVM kernel on node crdvm1 as well.

[Guilherme G. Piccoli (gpiccoli)]

Observed in H/KVM, cycle sru-20210531 .

[Guilherme G. Piccoli (gpiccoli)]

Observed in G/KVM, cycle sru-20210531 .

[Guilherme G. Piccoli (gpiccoli)]

Observed in F/KVM, cycle sru-20210531 .

[Guilherme G. Piccoli (gpiccoli)]

Observed in B/KVM, cycle sru-20210531 .

[Po-Hsu Lin (cypressyew)]

I think this has something to do with the KVM host, as I can reproduce this on the same KVM node "zeppo" with both 5.11.0-18-generic and the 5.11.0-1008-kvm

[Guilherme G. Piccoli (gpiccoli)]

I agree @cypressyew ! I just found in T-4.15/Azure.

[Po-Hsu Lin (cypressyew)]

I can reproduce this with KVM node larry running with OEM 5.10 kernel.
Our KVM node was hosted on a bionic server, I will give focal / hirsute server a try.