[PATCH] btrfs: validate device maj:min during scan

[Anand Jain <anand.jain@oracle.com>]

The maj:min of a device can change without altering the device path.
When the device is re-scanned, only the device path change is fixed,
if any, but the changed maj:min remains (bug). This patch fixes it by
also checking for the changed maj:min.

However, please note that we still need to validate the maj:min during
open as in the patch ("btrfs: validate device maj:min during open") because
only the device specified in the mount command gets scanned during mount.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
---
 fs/btrfs/volumes.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index 8a35605822bf..473f03965f26 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -854,7 +854,8 @@ static noinline struct btrfs_device *device_list_add(const char *path,
 				MAJOR(path_devt), MINOR(path_devt),
 				current->comm, task_pid_nr(current));
 
-	} else if (!device->name || strcmp(device->name->str, path)) {
+	} else if (!device->name || strcmp(device->name->str, path) ||
+		   device->devt != path_devt) {
 		/*
 		 * When FS is already mounted.
 		 * 1. If you are here and if the device->name is NULL that
-- 
2.31.1