[PATCH] x86/resctrl: Only check Intel systems for SNC

[PATCH] x86/resctrl: Only check Intel systems for SNC

[Tony Luck]

topology_num_nodes_per_package() reports values greater than one on
certain AMD systems resulting in snc_get_config() printing the confusing
message "CoD enabled system? Resctrl not supported".

Add a check for Intel systems before looking at topology.

Fixes: 59674fc9d0bf ("x86/resctrl: Fix SNC detection")
Reported-by: Babu Moger Babu <babu.moger@amd.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Tested-by: Babu Moger Babu <babu.moger@amd.com>
---
 arch/x86/kernel/cpu/resctrl/monitor.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/arch/x86/kernel/cpu/resctrl/monitor.c b/arch/x86/kernel/cpu/resctrl/monitor.c
index 9bd87bae4983..59215fef3924 100644
--- a/arch/x86/kernel/cpu/resctrl/monitor.c
+++ b/arch/x86/kernel/cpu/resctrl/monitor.c
@@ -377,7 +377,12 @@ static const struct x86_cpu_id snc_cpu_ids[] __initconst = {
 
 static __init int snc_get_config(void)
 {
-	int ret = topology_num_nodes_per_package();
+	int ret;
+
+	if (boot_cpu_data.x86_vendor != X86_VENDOR_INTEL)
+		return 1;
+
+	ret = topology_num_nodes_per_package();
 
 	if (ret > 1 && !x86_match_cpu(snc_cpu_ids)) {
 		pr_warn("CoD enabled system? Resctrl not supported\n");
-- 
2.53.0

Re: [PATCH] x86/resctrl: Only check Intel systems for SNC

[Babu Moger]

+ Reinette:

On 4/28/26 18:26, Tony Luck wrote:
> topology_num_nodes_per_package() reports values greater than one on
> certain AMD systems resulting in snc_get_config() printing the confusing
> message "CoD enabled system? Resctrl not supported".
> 
> Add a check for Intel systems before looking at topology.
> 
> Fixes: 59674fc9d0bf ("x86/resctrl: Fix SNC detection")
> Reported-by: Babu Moger Babu <babu.moger@amd.com>

Should be:

Reported-by: Babu Moger <babu.moger@amd.com>

> Signed-off-by: Tony Luck <tony.luck@intel.com>
> Tested-by: Babu Moger Babu <babu.moger@amd.com>

Should be:

Tested-by: Babu Moger <babu.moger@amd.com>

> ---
>   arch/x86/kernel/cpu/resctrl/monitor.c | 7 ++++++-
>   1 file changed, 6 insertions(+), 1 deletion(-)
> 
> diff --git a/arch/x86/kernel/cpu/resctrl/monitor.c b/arch/x86/kernel/cpu/resctrl/monitor.c
> index 9bd87bae4983..59215fef3924 100644
> --- a/arch/x86/kernel/cpu/resctrl/monitor.c
> +++ b/arch/x86/kernel/cpu/resctrl/monitor.c
> @@ -377,7 +377,12 @@ static const struct x86_cpu_id snc_cpu_ids[] __initconst = {
>   
>   static __init int snc_get_config(void)
>   {
> -	int ret = topology_num_nodes_per_package();
> +	int ret;
> +
> +	if (boot_cpu_data.x86_vendor != X86_VENDOR_INTEL)
> +		return 1;
> +
> +	ret = topology_num_nodes_per_package();
>   
>   	if (ret > 1 && !x86_match_cpu(snc_cpu_ids)) {
>   		pr_warn("CoD enabled system? Resctrl not supported\n");