Re: [PATCH 0/3] KVM: x86: Fix Intel PT Host/Guest mode when host tracing also

[Adrian Hunter]

On 26/09/24 17:05, Adrian Hunter wrote:
> On 6/09/24 16:00, Adrian Hunter wrote:
>> Hi
>>
>> There is a long-standing problem whereby running Intel PT on host and guest
>> in Host/Guest mode, causes VM-Entry failure.
>>
>> The motivation for this patch set is to provide a fix for stable kernels
>> prior to the advent of the "Mediated Passthrough vPMU" patch set:
>>
>> 	https://lore.kernel.org/kvm/20240801045907.4010984-1-mizhang@xxxxxxxxxx/
>>
>> which would render a large part of the fix unnecessary but likely not be
>> suitable for backport to stable due to its size and complexity.
>>
>> Ideally, this patch set would be applied before "Mediated Passthrough vPMU"
>>
>> Note that the fix does not conflict with "Mediated Passthrough vPMU", it
>> is just that "Mediated Passthrough vPMU" will make the code to stop and
>> restart Intel PT unnecessary.
> 
> Any comments?

Any comments?

> 
>>
>>
>> Adrian Hunter (3):
>>       KVM: x86: Fix Intel PT IA32_RTIT_CTL MSR validation
>>       KVM: x86: Fix Intel PT Host/Guest mode when host tracing also
>>       KVM: selftests: Add guest Intel PT test
>>
>>  arch/x86/events/intel/pt.c                         | 131 ++++++-
>>  arch/x86/events/intel/pt.h                         |  10 +
>>  arch/x86/include/asm/intel_pt.h                    |   4 +
>>  arch/x86/kvm/vmx/vmx.c                             |  26 +-
>>  arch/x86/kvm/vmx/vmx.h                             |   1 -
>>  tools/testing/selftests/kvm/Makefile               |   1 +
>>  .../selftests/kvm/include/x86_64/processor.h       |   1 +
>>  tools/testing/selftests/kvm/x86_64/intel_pt.c      | 381 +++++++++++++++++++++
>>  8 files changed, 532 insertions(+), 23 deletions(-)
>>  create mode 100644 tools/testing/selftests/kvm/x86_64/intel_pt.c
>>
>> base-commit: d45aab436cf06544abeeffc607110f559a3af3b4
>>
>>
>> Regards
>> Adrian
>