Re: [RESEND PATCH] perf/x86/amd: Do not touch the AMD64_EVENTSEL_HOSTONLY bit inside the guest

[Like Xu]

On 24/7/2021 4:16 am, Kim Phillips wrote:
> +Tom L., Robert R.
>
> On 7/20/21 6:26 AM, Like Xu wrote:
> > From: Like Xu <likexu@xxxxxxxxxxx>
> >
> > If we use "perf record" in an AMD Milan guest, dmesg reports a #GP
> > warning from an unchecked MSR access error on MSR_F15H_PERF_CTLx:
> >
> > [] unchecked MSR access error: WRMSR to 0xc0010200 (tried to write
> > 0x0000020000110076) at rIP: 0xffffffff8106ddb4 
> > (native_write_msr+0x4/0x20)
> > [] Call Trace:
> > []  amd_pmu_disable_event+0x22/0x90
> > []  x86_pmu_stop+0x4c/0xa0
> > []  x86_pmu_del+0x3a/0x140
> >
> > The AMD64_EVENTSEL_HOSTONLY bit is defined and used on the host,
> > while the guest perf driver should avoid such use.
> >
> > Signed-off-by: Like Xu <likexu@xxxxxxxxxxx>
> > ---
>
> Tested-by: Kim Phillips <kim.phillips@xxxxxxx>

Thanks Kim.

Hi Peter, should I post a new version with the fix tag ?

> If we were to add a Fixes: tag, would this be the right commit?:
>
> commit 1018faa6cf23b256bf25919ef203cd7c129f06f2
>
> Author: Joerg Roedel <joerg.roedel@xxxxxxx>
>
> Date:   Wed Feb 29 14:57:32 2012 +0100
>
>
>
>      perf/x86/kvm: Fix Host-Only/Guest-Only counting with SVM disabled
>
>
> Thanks,
>
> Kim