mount: filesystems mounted in the initrd should not conflict with umount.target in the real root

These mounts should be kept around and unmounted in the shutdown ramfs.

Currently, we will still attempt to umount these in the final kill spree, but
we should consider avoiding that too. Also, the should_umount function should
be generalised and put into util.c or something like that, but we are still
discussing precisely how.

1 files changed, 21 insertions, 5 deletions

diff --git a/src/core/mount.c b/src/core/mount.c
index d436a84606..5c18d4e463 100644
--- a/src/core/mount.c
+++ b/src/core/mount.c
@@ -447,6 +447,21 @@ static int mount_add_quota_links(Mount *m) {
         return 0;
 }
 
+static bool should_umount(Mount *m) {
+        MountParameters *p;
+
+        if (path_equal(m->where, "/") ||
+            path_equal(m->where, "/usr"))
+                return false;
+
+        p = get_mount_parameters(m);
+        if (p && mount_test_option(p->options, "x-initrd.mount") &&
+            !in_initrd())
+                return false;
+
+        return true;
+}
+
 static int mount_add_default_dependencies(Mount *m) {
         const char *after, *after2, *online;
         MountParameters *p;
@@ -491,9 +506,11 @@ static int mount_add_default_dependencies(Mount *m) {
                         return r;
         }
 
-        r = unit_add_two_dependencies_by_name(UNIT(m), UNIT_BEFORE, UNIT_CONFLICTS, SPECIAL_UMOUNT_TARGET, NULL, true);
-        if (r < 0)
-                return r;
+        if (should_umount(m)) {
+                r = unit_add_two_dependencies_by_name(UNIT(m), UNIT_BEFORE, UNIT_CONFLICTS, SPECIAL_UMOUNT_TARGET, NULL, true);
+                if (r < 0)
+                        return r;
+        }
 
         return 0;
 }
@@ -1553,8 +1570,7 @@ static int mount_add_one(
                 if (r < 0)
                         goto fail;
 
-                if (!path_equal(where, "/") &&
-                    !path_equal(where, "/usr")) {
+                if (should_umount(MOUNT(u))) {
                         r = unit_add_dependency_by_name(u, UNIT_CONFLICTS, SPECIAL_UMOUNT_TARGET, NULL, true);
                         if (r < 0)
                                 goto fail;