[PATCH] misc: fs_loader: Fix alignment of fs_loader driver

[Heinrich Schuchardt]

On 9/30/23 22:45, Sean Anderson wrote:
> DM_DRIVER_GET will redeclare the fs_loader driver without the correct
> alignment. This causes GCC to use the default section alignment of 32
> bytes. This in turn creates a gap in the linker list due to the padding
> required to achieve the correct alignment, corrupting all further entries.
> Use DM_DRIVER_REF instead, which doesn't redeclare anything.

doc/api/linker_lists.rst describes this problem.

We are using DM_DRIVER_GET() a lot and DM_DRIVER_REF() rarely.

I have seen that ll_entry_get exists since 2012 when Marek introduced
linker lists into U-Boot and ll_entry_ref since 2021.

In which use cases are ll_entry_get() and DM_DRIVER_GET() really needed?
Or can they both be completely replaced by ll_entry_ref() and
DM_DRIVER_REF().

Best regards

Heinrich

>
> Fixes: 0998a20cfc6 ("misc: fs_loader: Add function to get the chosen loader")
> Signed-off-by: Sean Anderson <seanga2 at gmail.com>
> ---
>
>   drivers/misc/fs_loader.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/misc/fs_loader.c b/drivers/misc/fs_loader.c
> index ccf5c7a8037..1ffc199ba1e 100644
> --- a/drivers/misc/fs_loader.c
> +++ b/drivers/misc/fs_loader.c
> @@ -316,7 +316,7 @@ int get_fs_loader(struct udevice **dev)
>   		return ret;
>
>   	/* Just create a new device */
> -	ret = device_bind(dm_root(), DM_DRIVER_GET(fs_loader), "default-loader",
> +	ret = device_bind(dm_root(), DM_DRIVER_REF(fs_loader), "default-loader",
>   			  &default_plat, ofnode_null(), dev);
>   	if (ret)
>   		return ret;