btrfs: remove impossible WARN_ON in btrfs_destroy_dev_replace_tgtdev()

We have a user report, that cppcheck is complaining about a possible
NULL-pointer dereference in btrfs_destroy_dev_replace_tgtdev().

We're first dereferencing the 'tgtdev' variable and the later check for
the validity of the pointer with a WARN_ON(!tgtdev);

But all callers of btrfs_destroy_dev_replace_tgtdev() either explicitly
check if 'tgtdev' is non-NULL or directly allocate 'tgtdev', so the
WARN_ON() is impossible to hit. Just remove it to silence the checker's
complains.

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=205003
Signed-off-by: Johannes Thumshirn <jth@kernel.org>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index b1bcd245ec66ece560540a535dee3de10a8154e8..07ef3d924aaeb00efa714dd9887b7fe26800c1a6 100644 (file)
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -2132,7 +2132,6 @@ void btrfs_destroy_dev_replace_tgtdev(struct btrfs_device *tgtdev)
 {
        struct btrfs_fs_devices *fs_devices = tgtdev->fs_info->fs_devices;
 
-       WARN_ON(!tgtdev);
        mutex_lock(&fs_devices->device_list_mutex);
 
        btrfs_sysfs_rm_device_link(fs_devices, tgtdev);