merge from trunk

1 files changed, 31 insertions, 2 deletions

diff --git a/cloudinit/config/cc_resizefs.py b/cloudinit/config/cc_resizefs.py
index 95bc7a4e..be406034 100644
--- a/cloudinit/config/cc_resizefs.py
+++ b/cloudinit/config/cc_resizefs.py
@@ -56,6 +56,25 @@ RESIZE_FS_PREFIXES_CMDS = [
 NOBLOCK = "noblock"
 
 
+def rootdev_from_cmdline(cmdline):
+    found = None
+    for tok in cmdline.split():
+        if tok.startswith("root="):
+            found = tok[5:]
+            break
+    if found is None:
+        return None
+
+    if found.startswith("/dev/"):
+        return found
+    if found.startswith("LABEL="):
+        return "/dev/disk/by-label/" + found[len("LABEL="):]
+    if found.startswith("UUID="):
+        return "/dev/disk/by-uuid/" + found[len("UUID="):]
+
+    return "/dev/" + found
+
+
 def handle(name, cfg, _cloud, log, args):
     if len(args) != 0:
         resize_root = args[0]
@@ -83,10 +102,20 @@ def handle(name, cfg, _cloud, log, args):
     info = "dev=%s mnt_point=%s path=%s" % (devpth, mount_point, resize_what)
     log.debug("resize_info: %s" % info)
 
+    container = util.is_container()
+
+    if (devpth == "/dev/root" and not os.path.exists(devpth) and
+        not container):
+        devpth = rootdev_from_cmdline(util.get_cmdline())
+        if devpth is None:
+            log.warn("Unable to find device '/dev/root'")
+            return
+        log.debug("Converted /dev/root to '%s' per kernel cmdline", devpth)
+
     try:
         statret = os.stat(devpth)
     except OSError as exc:
-        if util.is_container() and exc.errno == errno.ENOENT:
+        if container and exc.errno == errno.ENOENT:
             log.debug("Device '%s' did not exist in container. "
                       "cannot resize: %s" % (devpth, info))
         elif exc.errno == errno.ENOENT:
@@ -97,7 +126,7 @@ def handle(name, cfg, _cloud, log, args):
         return
 
     if not stat.S_ISBLK(statret.st_mode) and not stat.S_ISCHR(statret.st_mode):
-        if util.is_container():
+        if container:
             log.debug("device '%s' not a block device in container."
                       " cannot resize: %s" % (devpth, info))
         else: