The resctrl selftest currently fails on Hygon CPUs that always supports
non-contiguous CBM, printing the error:

  "# Hardware and kernel differ on non-contiguous CBM support!"

This occurs because the arch_supports_noncont_cat() function lacks
vendor detection for Hygon CPUs, preventing proper identification of
their non-contiguous CBM capability.

Fix this by adding Hygon vendor ID detection to
arch_supports_noncont_cat().

Signed-off-by: Xiaochen Shen <shenxiaochen@open-hieco.net>
---
 tools/testing/selftests/resctrl/cat_test.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/tools/testing/selftests/resctrl/cat_test.c b/tools/testing/selftests/resctrl/cat_test.c
index 94cfdba5308d..59a0f80fdc5a 100644
--- a/tools/testing/selftests/resctrl/cat_test.c
+++ b/tools/testing/selftests/resctrl/cat_test.c
@@ -290,8 +290,8 @@ static int cat_run_test(const struct resctrl_test *test, const struct user_param
 
 static bool arch_supports_noncont_cat(const struct resctrl_test *test)
 {
-	/* AMD always supports non-contiguous CBM. */
-	if (get_vendor() == ARCH_AMD)
+	/* AMD and Hygon always supports non-contiguous CBM. */
+	if (get_vendor() == ARCH_AMD || get_vendor() == ARCH_HYGON)
 		return true;
 
 #if defined(__i386__) || defined(__x86_64__) /* arch */
-- 
2.47.3

Hi Xiaochen,

On 12/4/25 4:38 AM, Xiaochen Shen wrote:
> The resctrl selftest currently fails on Hygon CPUs that always supports
> non-contiguous CBM, printing the error:
> 
>   "# Hardware and kernel differ on non-contiguous CBM support!"
> 
> This occurs because the arch_supports_noncont_cat() function lacks
> vendor detection for Hygon CPUs, preventing proper identification of
> their non-contiguous CBM capability.
> 
> Fix this by adding Hygon vendor ID detection to
> arch_supports_noncont_cat().
> 
> Signed-off-by: Xiaochen Shen <shenxiaochen@open-hieco.net>
> ---

I think it may help to add a maintainer note here to highlight even though this
is a fix it is not a candidate for backport since, based on your other series,
support for Hygon is in process of being added to resctrl.

>  tools/testing/selftests/resctrl/cat_test.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/tools/testing/selftests/resctrl/cat_test.c b/tools/testing/selftests/resctrl/cat_test.c
> index 94cfdba5308d..59a0f80fdc5a 100644
> --- a/tools/testing/selftests/resctrl/cat_test.c
> +++ b/tools/testing/selftests/resctrl/cat_test.c
> @@ -290,8 +290,8 @@ static int cat_run_test(const struct resctrl_test *test, const struct user_param
>  
>  static bool arch_supports_noncont_cat(const struct resctrl_test *test)
>  {
> -	/* AMD always supports non-contiguous CBM. */
> -	if (get_vendor() == ARCH_AMD)
> +	/* AMD and Hygon always supports non-contiguous CBM. */
> +	if (get_vendor() == ARCH_AMD || get_vendor() == ARCH_HYGON)
>  		return true;
>  
>  #if defined(__i386__) || defined(__x86_64__) /* arch */

Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>

Reinette

Hi Reinette,

On 12/5/2025 8:55 AM, Reinette Chatre wrote:
>> Signed-off-by: Xiaochen Shen <shenxiaochen@open-hieco.net>
>> ---
> I think it may help to add a maintainer note here to highlight even though this
> is a fix it is not a candidate for backport since, based on your other series,
> support for Hygon is in process of being added to resctrl.
>

Great suggestion.
I will add a maintainer note as you suggested in v2 patch series.

 
>>  tools/testing/selftests/resctrl/cat_test.c | 4 ++--
>>  1 file changed, 2 insertions(+), 2 deletions(-)
> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
> 
> Reinette

Thank you very much for code review!


Best regards,
Xiaochen Shen