diff --git a/scripts/autotest_common.sh b/scripts/autotest_common.sh
index 1976d6a4a..d81bd44df 100755
--- a/scripts/autotest_common.sh
+++ b/scripts/autotest_common.sh
@@ -207,6 +207,22 @@ function waitfornbd() {
 
 	for ((i=1; i<=20; i++)); do
 		if grep -q -w $nbd_name /proc/partitions; then
+			break
+		else
+			sleep 0.1
+		fi
+	done
+
+	# The nbd device is now recognized as a block device, but there can be
+	#  a small delay before we can start I/O to that block device.  So loop
+	#  here trying to read the first block of the nbd block device to a temp
+	#  file.  Note that dd returns success when reading an empty file, so we
+	#  need to check the size of the output file instead.
+	for ((i=1; i<=20; i++)); do
+		dd if=/dev/$nbd_name of=/tmp/nbdtest bs=4096 count=1 iflag=direct
+		size=`stat -c %s /tmp/nbdtest`
+		rm -f /tmp/nbdtest
+		if [ "$size" != "0" ]; then
 			return 0
 		else
 			sleep 0.1