linux-kernel - Re: [PATCH v3 1/9] perf/x86/intel: Fix a comment about guest LBR support

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

Date:   Wed, 3 Mar 2021 08:49:23 -0800
From:   Sean Christopherson <seanjc@...gle.com>
To:     Like Xu <like.xu@...ux.intel.com>
Cc:     Peter Zijlstra <peterz@...radead.org>,
        Paolo Bonzini <pbonzini@...hat.com>,
        Vitaly Kuznetsov <vkuznets@...hat.com>,
        Wanpeng Li <wanpengli@...cent.com>,
        Jim Mattson <jmattson@...gle.com>,
        Joerg Roedel <joro@...tes.org>,
        Kan Liang <kan.liang@...ux.intel.com>,
        Dave Hansen <dave.hansen@...el.com>, wei.w.wang@...el.com,
        Borislav Petkov <bp@...en8.de>, kvm@...r.kernel.org,
        x86@...nel.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH v3 1/9] perf/x86/intel: Fix a comment about guest LBR
 support

On Wed, Mar 03, 2021, Like Xu wrote:
> Starting from v5.12, KVM reports guest LBR and extra_regs
> support when the host has relevant support.
> 
> Cc: Peter Zijlstra <peterz@...radead.org>
> Reviewed-by: Kan Liang <kan.liang@...ux.intel.com>
> Signed-off-by: Like Xu <like.xu@...ux.intel.com>
> ---
>  arch/x86/events/intel/core.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/arch/x86/events/intel/core.c b/arch/x86/events/intel/core.c
> index d4569bfa83e3..a32acc7733a7 100644
> --- a/arch/x86/events/intel/core.c
> +++ b/arch/x86/events/intel/core.c
> @@ -5565,7 +5565,7 @@ __init int intel_pmu_init(void)
>  
>  	/*
>  	 * Access LBR MSR may cause #GP under certain circumstances.
> -	 * E.g. KVM doesn't support LBR MSR
> +	 * E.g. KVM doesn't support LBR MSR before v5.12.

Just delete this part of the comment.

>  	 * Check all LBT MSR here.
>  	 * Disable LBR access if any LBR MSRs can not be accessed.
>  	 */
> -- 
> 2.29.2
>