diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c
index 98bd3aab9739114f6b4dd1a538928856929fe7a5..638cff41d436777fa85afc31dfd6213f227b2637 100644
--- a/drivers/scsi/sd.c
+++ b/drivers/scsi/sd.c
@@ -1215,7 +1215,7 @@ sd_read_capacity(struct scsi_disk *sdkp, char *diskname,
 		/* Either no media are present but the drive didn't tell us,
 		   or they are present but the read capacity command fails */
 		/* sdkp->media_present = 0; -- not always correct */
-		sdkp->capacity = 0x200000; /* 1 GB - random */
+		sdkp->capacity = 0; /* unknown mapped to zero - as usual */
 
 		return;
 	} else if (the_result && longrc) {