mkefidisk.sh: fix hanging on non-writeable device

If cleanup() is called early on, as happens when the device isn't
writeable, then none of the mount point variables are set; thus the
script was calling grep with only one argument and appeared to hang
since it was waiting for input on stdin.

(From OE-Core rev: cf4a18eec2a65d840352d1a2862242d116e8a409)

Signed-off-by: Paul Eggleton <paul.eggleton@linux.intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

1 files changed, 3 insertions, 0 deletions

diff --git a/scripts/contrib/mkefidisk.sh b/scripts/contrib/mkefidisk.sh
index 74cf40d551..d6bc965137 100755
--- a/scripts/contrib/mkefidisk.sh
+++ b/scripts/contrib/mkefidisk.sh
@@ -136,6 +136,9 @@ unmount_device() {
 }
 
 unmount() {
+        if [ "$1" = "" ] ; then
+                return 0
+        fi
         grep -q $1 /proc/mounts
         if [ $? -eq 0 ]; then
                 debug "Unmounting $1"