[PATCH 07/28] ceph: avoid false positive maybe-uninitialized warning

[Arnd Bergmann]

A recent rework removed the initialization of the local 'root'
variable that is returned from ceph_real_mount:

fs/ceph/super.c: In function 'ceph_mount':
fs/ceph/super.c:1016:38: error: 'root' may be used uninitialized in this function [-Werror=maybe-uninitialized]

It's not obvious to me what the correct fix is, so this just
returns the saved root as we did before.

Fixes: ce2728aaa82b ("ceph: avoid accessing / when mounting a subpath")
Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
Cc: "Yan, Zheng" <zyan@xxxxxxxxxx>
---
 fs/ceph/super.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/fs/ceph/super.c b/fs/ceph/super.c
index a29ffce..79a4be8 100644
--- a/fs/ceph/super.c
+++ b/fs/ceph/super.c
@@ -821,7 +821,8 @@ static struct dentry *ceph_real_mount(struct ceph_fs_client *fsc)
 	dout("mount start %p\n", fsc);
 	mutex_lock(&fsc->client->mount_mutex);
 
-	if (!fsc->sb->s_root) {
+	root = dget(fsc->sb->s_root);
+	if (!root) {
 		const char *path;
 		err = __ceph_open_session(fsc->client, started);
 		if (err < 0)
-- 
2.9.0