Index: geom_io.c
===================================================================
RCS file: /usr/repo/src/sys/geom/geom_io.c,v
retrieving revision 1.71
diff -u -p -r1.71 geom_io.c
--- geom_io.c	31 Oct 2006 21:11:20 -0000	1.71
+++ geom_io.c	28 Jan 2007 11:45:13 -0000
@@ -343,9 +343,13 @@ g_io_request(struct bio *bp, struct g_co
 	bp->_bio_cflags = bp->bio_cflags;
 #endif
 
-	if (bp->bio_cmd & (BIO_READ|BIO_WRITE|BIO_DELETE|BIO_GETATTR)) {
+	if (bp->bio_cmd & (BIO_READ|BIO_WRITE|BIO_GETATTR)) {
 		KASSERT(bp->bio_data != NULL,
-		    ("NULL bp->data in g_io_request"));
+		    ("NULL bp->data in g_io_request(cmd=%hhu)", bp->bio_cmd));
+	}
+	if (bp->bio_cmd & (BIO_DELETE|BIO_FLUSH)) {
+		KASSERT(bp->bio_data == NULL,
+		    ("non-NULL bp->data in g_io_request(cmd=%hhu)", bp->bio_cmd));
 	}
 	if (bp->bio_cmd & (BIO_READ|BIO_WRITE|BIO_DELETE)) {
 		KASSERT(bp->bio_offset % cp->provider->sectorsize == 0,