overlayfs: Allow not used mount points

When machine configuration defines a mount point, which is not used in
any recipe, allow to fall through and only report a note in the logs.
This can be expected behavior, when a mount point is defined for several
machines, but not used in all of them

(From OE-Core rev: c7c6b273656a3e2b8b959004b996e56d4086ce5e)

Signed-off-by: Vyacheslav Yurkov <Vyacheslav.Yurkov@bruker.com>
Signed-off-by: Luca Ceresoli <luca.ceresoli@bootlin.com>
(cherry picked from commit a9c604b5e0d943b5b5f7c8bdd5be730c2abcf866)
Signed-off-by: Steve Sakoman <steve@sakoman.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

2 files changed, 10 insertions, 2 deletions

diff --git a/meta/classes-recipe/overlayfs.bbclass b/meta/classes-recipe/overlayfs.bbclass
index bdc6dd9d57..53d65d7531 100644
--- a/meta/classes-recipe/overlayfs.bbclass
+++ b/meta/classes-recipe/overlayfs.bbclass
@@ -102,7 +102,11 @@ python do_create_overlayfs_units() {
     overlayMountPoints = d.getVarFlags("OVERLAYFS_MOUNT_POINT")
     for mountPoint in overlayMountPoints:
         bb.debug(1, "Process variable flag %s" % mountPoint)
-        for lower in d.getVarFlag('OVERLAYFS_WRITABLE_PATHS', mountPoint).split():
+        lowerList = d.getVarFlag('OVERLAYFS_WRITABLE_PATHS', mountPoint)
+        if not lowerList:
+            bb.note("No mount points defined for %s flag, skipping" % (mountPoint))
+            continue
+        for lower in lowerList.split():
             bb.debug(1, "Prepare mount unit for %s with data mount point %s" %
                      (lower, d.getVarFlag('OVERLAYFS_MOUNT_POINT', mountPoint)))
             prepareUnits(d.getVarFlag('OVERLAYFS_MOUNT_POINT', mountPoint), lower)
diff --git a/meta/lib/oe/overlayfs.py b/meta/lib/oe/overlayfs.py
index 8d7a047125..8b88900f71 100644
--- a/meta/lib/oe/overlayfs.py
+++ b/meta/lib/oe/overlayfs.py
@@ -40,7 +40,11 @@ def unitFileList(d):
             bb.fatal("Missing required mount point for OVERLAYFS_MOUNT_POINT[%s] in your MACHINE configuration" % mountPoint)
 
     for mountPoint in overlayMountPoints:
-        for path in d.getVarFlag('OVERLAYFS_WRITABLE_PATHS', mountPoint).split():
+        mountPointList = d.getVarFlag('OVERLAYFS_WRITABLE_PATHS', mountPoint)
+        if not mountPointList:
+            bb.debug(1, "No mount points defined for %s flag, don't add to file list", mountPoint)
+            continue
+        for path in mountPointList.split():
             fileList.append(mountUnitName(path))
             fileList.append(helperUnitName(path))