diff --git a/block/blk-settings.c b/block/blk-settings.c
index a7a794baba72..07874e9b609f 100644
--- a/block/blk-settings.c
+++ b/block/blk-settings.c
@@ -400,12 +400,19 @@ int blk_validate_limits(struct queue_limits *lim)
 	lim->max_discard_sectors =
 		min(lim->max_hw_discard_sectors, lim->max_user_discard_sectors);
 
+	/*
+	 * When discard is not supported, discard_granularity should be reported
+	 * as 0 to userspace.
+	 */
+	if (lim->max_discard_sectors)
+		lim->discard_granularity =
+			max(lim->discard_granularity, lim->physical_block_size);
+	else
+		lim->discard_granularity = 0;
+
 	if (!lim->max_discard_segments)
 		lim->max_discard_segments = 1;
 
-	if (lim->discard_granularity < lim->physical_block_size)
-		lim->discard_granularity = lim->physical_block_size;
-
 	/*
 	 * By default there is no limit on the segment boundary alignment,
 	 * but if there is one it can't be smaller than the page size as