[v4] powerpc/pseries/Kconfig: Enable CONFIG_VPA_PMU to be used with KVM

[PATCH v4] powerpc/pseries/Kconfig: Enable CONFIG_VPA_PMU to be used with KVM

Posted by Gautam Menghani 5 days, 15 hours ago

Currently, CONFIG_VPA_PMU is not enabled by default, and consequently
cannot be used for KVM guests at all, unless explicitly enabled on
host kernel.

Mark CONFIG_VPA_PMU as "default m" to ensure it is available when KVM is
being used.

Fixes: 176cda0619b6c ("powerpc/perf: Add perf interface to expose vpa counters")
Cc: stable@vger.kernel.org # v6.13+
Suggested-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Gautam Menghani <gautam@linux.ibm.com>
---
v3 -> v4:
1. Reword the patch description (Harsh)

v2 -> v3:
1. Make CONFIG_VPA_PMU as default m so that it can separately disabled
(Sean)

v1 -> v2:
1. Rebased on latest master

 arch/powerpc/platforms/pseries/Kconfig | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/powerpc/platforms/pseries/Kconfig b/arch/powerpc/platforms/pseries/Kconfig
index f7052b131a4c..74910ce3a541 100644
--- a/arch/powerpc/platforms/pseries/Kconfig
+++ b/arch/powerpc/platforms/pseries/Kconfig
@@ -154,6 +154,7 @@ config HV_PERF_CTRS
 config VPA_PMU
 	tristate "VPA PMU events"
 	depends on KVM_BOOK3S_64_HV && HV_PERF_CTRS
+	default m
 	help
 	  Enable access to the VPA PMU counters via perf. This enables
 	  code that support measurement for KVM on PowerVM(KoP) feature.
-- 
2.53.0

Re: [PATCH v4] powerpc/pseries/Kconfig: Enable CONFIG_VPA_PMU to be used with KVM

Posted by Ritesh Harjani (IBM) 2 days ago

Gautam Menghani <gautam@linux.ibm.com> writes:

> Currently, CONFIG_VPA_PMU is not enabled by default, and consequently
> cannot be used for KVM guests at all, unless explicitly enabled on
> host kernel.
>
> Mark CONFIG_VPA_PMU as "default m" to ensure it is available when KVM is
> being used.
>
> Fixes: 176cda0619b6c ("powerpc/perf: Add perf interface to expose vpa counters")

Not really a fix per-se. So we need not add this fixes tag.

> Cc: stable@vger.kernel.org # v6.13+

I think the stable tag like above is sufficient for stable tree
maintainers to pick this up.

-ritesh

Re: [PATCH v4] powerpc/pseries/Kconfig: Enable CONFIG_VPA_PMU to be used with KVM

Posted by Amit Machhiwal 5 days, 8 hours ago

On 2026/06/02 05:47 PM, Gautam Menghani wrote:
> Currently, CONFIG_VPA_PMU is not enabled by default, and consequently
> cannot be used for KVM guests at all, unless explicitly enabled on
> host kernel.
> 
> Mark CONFIG_VPA_PMU as "default m" to ensure it is available when KVM is
> being used.
> 
> Fixes: 176cda0619b6c ("powerpc/perf: Add perf interface to expose vpa counters")
> Cc: stable@vger.kernel.org # v6.13+
> Suggested-by: Sean Christopherson <seanjc@google.com>
> Signed-off-by: Gautam Menghani <gautam@linux.ibm.com>
> ---
> v3 -> v4:
> 1. Reword the patch description (Harsh)
> 
> v2 -> v3:
> 1. Make CONFIG_VPA_PMU as default m so that it can separately disabled
> (Sean)
> 
> v1 -> v2:
> 1. Rebased on latest master
> 
>  arch/powerpc/platforms/pseries/Kconfig | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/arch/powerpc/platforms/pseries/Kconfig b/arch/powerpc/platforms/pseries/Kconfig
> index f7052b131a4c..74910ce3a541 100644
> --- a/arch/powerpc/platforms/pseries/Kconfig
> +++ b/arch/powerpc/platforms/pseries/Kconfig
> @@ -154,6 +154,7 @@ config HV_PERF_CTRS
>  config VPA_PMU
>  	tristate "VPA PMU events"
>  	depends on KVM_BOOK3S_64_HV && HV_PERF_CTRS
> +	default m

LGTM.

Reviewed-by: Amit Machhiwal <amachhiw@linux.ibm.com>

Thanks,
Amit

Re: [PATCH v4] powerpc/pseries/Kconfig: Enable CONFIG_VPA_PMU to be used with KVM

Posted by Harsh Prateek Bora 5 days, 10 hours ago


On 02/06/26 5:47 pm, Gautam Menghani wrote:
> Currently, CONFIG_VPA_PMU is not enabled by default, and consequently
> cannot be used for KVM guests at all, unless explicitly enabled on
> host kernel.
> 
> Mark CONFIG_VPA_PMU as "default m" to ensure it is available when KVM is
> being used.
> 
> Fixes: 176cda0619b6c ("powerpc/perf: Add perf interface to expose vpa counters")
> Cc: stable@vger.kernel.org # v6.13+
> Suggested-by: Sean Christopherson <seanjc@google.com>
> Signed-off-by: Gautam Menghani <gautam@linux.ibm.com>
> ---
> v3 -> v4:
> 1. Reword the patch description (Harsh)
> 

Reviewed-by: Harsh Prateek Bora <harshpb@linux.ibm.com>

> v2 -> v3:
> 1. Make CONFIG_VPA_PMU as default m so that it can separately disabled
> (Sean)
> 
> v1 -> v2:
> 1. Rebased on latest master
> 
>   arch/powerpc/platforms/pseries/Kconfig | 1 +
>   1 file changed, 1 insertion(+)
> 
> diff --git a/arch/powerpc/platforms/pseries/Kconfig b/arch/powerpc/platforms/pseries/Kconfig
> index f7052b131a4c..74910ce3a541 100644
> --- a/arch/powerpc/platforms/pseries/Kconfig
> +++ b/arch/powerpc/platforms/pseries/Kconfig
> @@ -154,6 +154,7 @@ config HV_PERF_CTRS
>   config VPA_PMU
>   	tristate "VPA PMU events"
>   	depends on KVM_BOOK3S_64_HV && HV_PERF_CTRS
> +	default m
>   	help
>   	  Enable access to the VPA PMU counters via perf. This enables
>   	  code that support measurement for KVM on PowerVM(KoP) feature.