gpt-generator: Find device on a stateless system

A stateless system has a tmpfs as root file system. That obviously
does not have any block device associated with it. So try falling back
to the device of the /usr filesystem if the root filesystem fails.

1 files changed, 7 insertions, 2 deletions

diff --git a/src/gpt-auto-generator/gpt-auto-generator.c b/src/gpt-auto-generator/gpt-auto-generator.c
index 99dc50fe3c..96a8447efd 100644
--- a/src/gpt-auto-generator/gpt-auto-generator.c
+++ b/src/gpt-auto-generator/gpt-auto-generator.c
@@ -658,8 +658,13 @@ static int add_mounts(void) {
         if (r < 0)
                 return log_error_errno(r, "Failed to determine block device of root file system: %m");
         else if (r == 0) {
-                log_debug("Root file system not on a (single) block device.");
-                return 0;
+                r = get_block_device("/usr", &devno);
+                if (r < 0)
+                        return log_error_errno(r, "Failed to determine block device of /usr file system: %m");
+                else if (r == 0) {
+                        log_debug("Neither root nor /usr file system are on a (single) block device.");
+                        return 0;
+                }
         }
 
         return enumerate_partitions(devno);