drm/xe/vf: Add sanity check for GGTT configuration

The VF GGTT configuration was prepared by the PF, which should be
trusted, was obtained from the GuC, which likely already did some
sanity checks too, but since it's a received data, we should have
our own sanity checks to detect early any misconfiguration.

Signed-off-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Cc: Satyanarayana K V P <satyanarayana.k.v.p@intel.com>
Reviewed-by: Satyanarayana K V P <satyanarayana.k.v.p@intel.com>
Link: https://lore.kernel.org/r/20250602103325.549-4-michal.wajdeczko@intel.com

Author: mwajdecz

drivers/gpu/drm/xe/xe_tile_sriov_vf.c

@@ -11,6 +11,7 @@
 #include "xe_ggtt.h"
 #include "xe_gt_sriov_vf.h"
 #include "xe_sriov.h"
+#include "xe_sriov_printk.h"
 #include "xe_tile_sriov_vf.h"
 #include "xe_wopcm.h"
 
@@ -44,6 +45,7 @@ int xe_tile_sriov_vf_balloon_ggtt_locked(struct xe_tile *tile)
 	u64 ggtt_base = xe_gt_sriov_vf_ggtt_base(tile->primary_gt);
 	u64 ggtt_size = xe_gt_sriov_vf_ggtt(tile->primary_gt);
 	struct xe_device *xe = tile_to_xe(tile);
+	u64 wopcm = xe_wopcm_size(xe);
 	u64 start, end;
 	int err;
 
@@ -66,7 +68,14 @@ int xe_tile_sriov_vf_balloon_ggtt_locked(struct xe_tile *tile)
 	 *      |<--- balloon[0] --->|<-- VF -->|<-- balloon[1] ->|
 	 */
 
-	start = xe_wopcm_size(xe);
+	if (ggtt_base < wopcm || ggtt_base > GUC_GGTT_TOP ||
+	    ggtt_size > GUC_GGTT_TOP - ggtt_base) {
+		xe_sriov_err(xe, "tile%u: Invalid GGTT configuration: %#llx-%#llx\n",
+			     tile->id, ggtt_base, ggtt_base + ggtt_size - 1);
+		return -ERANGE;
+	}
+
+	start = wopcm;
 	end = ggtt_base;
 	if (end != start) {
 		err = xe_ggtt_node_insert_balloon_locked(tile->sriov.vf.ggtt_balloon[0],