X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?a=blobdiff_plain;f=src%2Fshared%2Fswitch-root.c;h=3adb8463c5f373d4cd316c4aab9337d2c3f289a9;hb=c73d180dc4bbd87c945a524b42b672af2ffe2609;hp=5f075e6003d90920a393fb202595b563bbf6df9b;hpb=5a4bf02ff57e4dd3453f2b868c72fe45f60033a3;p=elogind.git

diff --git a/src/shared/switch-root.c b/src/shared/switch-root.c
index 5f075e600..3adb8463c 100644
--- a/src/shared/switch-root.c
+++ b/src/shared/switch-root.c
@@ -47,7 +47,6 @@ int switch_root(const char *new_root, const char *oldroot, bool detach_oldroot,
         struct stat new_root_stat;
         bool old_root_remove;
         const char *i, *temporary_old_root;
-        int r;
 
         if (path_equal(new_root, "/"))
                 return 0;
@@ -62,10 +61,9 @@ int switch_root(const char *new_root, const char *oldroot, bool detach_oldroot,
                 return -errno;
         }
 
-        /* Work-around for a kernel bug: for some reason the kernel
-         * refuses switching root if any file systems are mounted
-         * MS_SHARED. Hence remount them MS_PRIVATE here as a
-         * work-around.
+        /* Work-around for kernel design: the kernel refuses switching
+         * root if any file systems are mounted MS_SHARED. Hence
+         * remount them MS_PRIVATE here as a work-around.
          *
          * https://bugzilla.redhat.com/show_bug.cgi?id=847418 */
         if (mount(NULL, "/", NULL, MS_REC|MS_PRIVATE, NULL) < 0)
@@ -104,11 +102,12 @@ int switch_root(const char *new_root, const char *oldroot, bool detach_oldroot,
                 }
         }
 
-        r = base_filesystem_create(new_root);
-        if (r < 0) {
-                log_error("Failed to create the base filesystem: %s", strerror(-r));
-                return r;
-        }
+        /* Do not fail, if base_filesystem_create() fails. Not all
+         * switch roots are like base_filesystem_create() wants them
+         * to look like. They might even boot, if they are RO and
+         * don't have the FS layout. Just ignore the error and
+         * switch_root() nevertheless. */
+        (void) base_filesystem_create(new_root);
 
         if (chdir(new_root) < 0) {
                 log_error("Failed to change directory to %s: %m", new_root);
@@ -128,10 +127,10 @@ int switch_root(const char *new_root, const char *oldroot, bool detach_oldroot,
 
                 /* Immediately get rid of the old root, if detach_oldroot is set.
                  * Since we are running off it we need to do this lazily. */
-                if (detach_oldroot && umount2(oldroot, MNT_DETACH) < 0) {
-                        log_error("Failed to umount old root dir %s: %m", oldroot);
-                        return -errno;
-                }
+                if (detach_oldroot && umount2(oldroot, MNT_DETACH) < 0)
+                        log_error("Failed to lazily umount old root dir %s, %s: %m",
+                                  oldroot,
+                                  errno == ENOENT ? "ignoring" : "leaving it around");
 
         } else if (mount(new_root, "/", NULL, MS_MOVE, NULL) < 0) {
                 log_error("Failed to mount moving %s to /: %m", new_root);