[PATCH v2 3/3] drm/xe/vf: Don't expose privileged GT debugfs files if VF

[Lucas De Marchi]

On Thu, Apr 03, 2025 at 04:26:35PM +0200, Michal Wajdeczko wrote:
>Some of the debugfs files require access to the registers that are
>not accessible to the VFs. Don't expose those files on VF drivers.
>
>Signed-off-by: Michal Wajdeczko <michal.wajdeczko at intel.com>
>Cc: Marcin Bernatowicz <marcin.bernatowicz at linux.intel.com>
>Cc: Lucas De Marchi <lucas.demarchi at intel.com>
>---
>v2: avoid "privileged" word, make it clear it's about VF/PF (Lucas)
>    add hint for developers where to add new files (Lucas)


Reviewed-by: Lucas De Marchi <lucas.demarchi at intel.com>

thanks
Lucas De Marchi

>---
> drivers/gpu/drm/xe/xe_gt_debugfs.c | 30 ++++++++++++++++++++++--------
> 1 file changed, 22 insertions(+), 8 deletions(-)
>
>diff --git a/drivers/gpu/drm/xe/xe_gt_debugfs.c b/drivers/gpu/drm/xe/xe_gt_debugfs.c
>index 2d63a69cbfa3..a88076e9cc7d 100644
>--- a/drivers/gpu/drm/xe/xe_gt_debugfs.c
>+++ b/drivers/gpu/drm/xe/xe_gt_debugfs.c
>@@ -299,20 +299,20 @@ static int hwconfig(struct xe_gt *gt, struct drm_printer *p)
> 	return 0;
> }
>
>-static const struct drm_info_list debugfs_list[] = {
>-	{"hw_engines", .show = xe_gt_debugfs_simple_show, .data = hw_engines},
>+/*
>+ * only for GT debugfs files which can be safely used on the VF as well:
>+ * - without access to the GT privileged registers
>+ * - without access to the PF specific data
>+ */
>+static const struct drm_info_list vf_safe_debugfs_list[] = {
> 	{"force_reset", .show = xe_gt_debugfs_simple_show, .data = force_reset},
> 	{"force_reset_sync", .show = xe_gt_debugfs_simple_show, .data = force_reset_sync},
> 	{"sa_info", .show = xe_gt_debugfs_simple_show, .data = sa_info},
> 	{"topology", .show = xe_gt_debugfs_simple_show, .data = topology},
>-	{"steering", .show = xe_gt_debugfs_simple_show, .data = steering},
> 	{"ggtt", .show = xe_gt_debugfs_simple_show, .data = ggtt},
>-	{"powergate_info", .show = xe_gt_debugfs_simple_show, .data = powergate_info},
> 	{"register-save-restore", .show = xe_gt_debugfs_simple_show, .data = register_save_restore},
> 	{"workarounds", .show = xe_gt_debugfs_simple_show, .data = workarounds},
> 	{"tunings", .show = xe_gt_debugfs_simple_show, .data = tunings},
>-	{"pat", .show = xe_gt_debugfs_simple_show, .data = pat},
>-	{"mocs", .show = xe_gt_debugfs_simple_show, .data = mocs},
> 	{"default_lrc_rcs", .show = xe_gt_debugfs_simple_show, .data = rcs_default_lrc},
> 	{"default_lrc_ccs", .show = xe_gt_debugfs_simple_show, .data = ccs_default_lrc},
> 	{"default_lrc_bcs", .show = xe_gt_debugfs_simple_show, .data = bcs_default_lrc},
>@@ -322,6 +322,15 @@ static const struct drm_info_list debugfs_list[] = {
> 	{"hwconfig", .show = xe_gt_debugfs_simple_show, .data = hwconfig},
> };
>
>+/* everything else should be added here */
>+static const struct drm_info_list pf_only_debugfs_list[] = {
>+	{"hw_engines", .show = xe_gt_debugfs_simple_show, .data = hw_engines},
>+	{"mocs", .show = xe_gt_debugfs_simple_show, .data = mocs},
>+	{"pat", .show = xe_gt_debugfs_simple_show, .data = pat},
>+	{"powergate_info", .show = xe_gt_debugfs_simple_show, .data = powergate_info},
>+	{"steering", .show = xe_gt_debugfs_simple_show, .data = steering},
>+};
>+
> void xe_gt_debugfs_register(struct xe_gt *gt)
> {
> 	struct xe_device *xe = gt_to_xe(gt);
>@@ -345,10 +354,15 @@ void xe_gt_debugfs_register(struct xe_gt *gt)
> 	 */
> 	root->d_inode->i_private = gt;
>
>-	drm_debugfs_create_files(debugfs_list,
>-				 ARRAY_SIZE(debugfs_list),
>+	drm_debugfs_create_files(vf_safe_debugfs_list,
>+				 ARRAY_SIZE(vf_safe_debugfs_list),
> 				 root, minor);
>
>+	if (!IS_SRIOV_VF(xe))
>+		drm_debugfs_create_files(pf_only_debugfs_list,
>+					 ARRAY_SIZE(pf_only_debugfs_list),
>+					 root, minor);
>+
> 	xe_uc_debugfs_register(&gt->uc, root);
>
> 	if (IS_SRIOV_PF(xe))
>-- 
>2.47.1
>