On Fri, Mar 08, 2024 at 08:15:07AM +0530, Anand Jain wrote:
> @@ -692,6 +692,16 @@ static int btrfs_open_one_device(struct btrfs_fs_devices *fs_devices,
> device->bdev = bdev_handle->bdev;
> clear_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &device->dev_state);
>
> + if (device->devt != device->bdev->bd_dev) {
> + btrfs_warn(NULL,
> + "device %s maj:min changed from %d:%d to %d:%d",
> + device->name->str, MAJOR(device->devt),
> + MINOR(device->devt), MAJOR(device->bdev->bd_dev),
> + MINOR(device->bdev->bd_dev));
> +
> + device->devt = device->bdev->bd_dev;
> + }
Just above this calls btrfs_get_bdev_and_sb, which calls
bdev_open_by_path. bdev_open_by_path bdev_open_by_path calls
lookup_bdev to translate the path to a dev_t and then calls
bdev_open_by_dev on the dev_t, which stored the passes in dev_t in
bdev->bd_dev. I see absolutely no way how this check could ever
trigger.
