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

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Message-ID: <b2671dab-9efa-4a56-bbe4-9b9140708120@intel.com>
Date: Thu, 26 Sep 2024 17:05:36 +0300
From: Adrian Hunter <adrian.hunter@...el.com>
To: Sean Christopherson <seanjc@...gle.com>,
 Paolo Bonzini <pbonzini@...hat.com>, Peter Zijlstra <peterz@...radead.org>
Cc: Zhenyu Wang <zhenyuw@...ux.intel.com>, kvm@...r.kernel.org,
 Shuah Khan <shuah@...nel.org>, linux-kselftest@...r.kernel.org,
 Ingo Molnar <mingo@...hat.com>, Thomas Gleixner <tglx@...utronix.de>,
 Borislav Petkov <bp@...en8.de>, Dave Hansen <dave.hansen@...ux.intel.com>,
 x86@...nel.org, H Peter Anvin <hpa@...or.com>,
 Mark Rutland <mark.rutland@....com>,
 Alexander Shishkin <alexander.shishkin@...ux.intel.com>,
 Arnaldo Carvalho de Melo <acme@...nel.org>, Jiri Olsa <jolsa@...nel.org>,
 Namhyung Kim <namhyung@...nel.org>, Ian Rogers <irogers@...gle.com>,
 Kan Liang <kan.liang@...ux.intel.com>, linux-kernel@...r.kernel.org,
 linux-perf-users@...r.kernel.org, mizhang@...gle.com
Subject: Re: [PATCH 0/3] KVM: x86: Fix Intel PT Host/Guest mode when host
 tracing also

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@google.com/
> 
> 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?

> 
> 
> 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