[PATCH v6 2/3] Boot var automatic management for removable medias

[Heinrich Schuchardt]

On 5/26/23 23:36, Raymond Mao wrote:
> Changes for complying to EFI spec §3.5.1.1
> 'Removable Media Boot Behavior'.
> Boot variables can be automatically generated during a removable
> media is probed. At the same time, unused boot variables will be
> detected and removed.
>
> Signed-off-by: Raymond Mao <raymond.mao at linaro.org>
> ---
> Changes in v3
> - Split the patch into moving and renaming functions and
>    individual patches for each changed functionality
> Changes in v5
> - Move function call of efi_bootmgr_update_media_device_boot_option()
>    from efi_init_variables() to efi_init_obj_list()
> Changes in v6
> - Revert unrelated changes
>
>   lib/efi_loader/efi_disk.c  | 7 +++++++
>   lib/efi_loader/efi_setup.c | 5 +++++
>   2 files changed, 12 insertions(+)
>
> diff --git a/lib/efi_loader/efi_disk.c b/lib/efi_loader/efi_disk.c
> index d2256713a8..ca5f07f2ec 100644
> --- a/lib/efi_loader/efi_disk.c
> +++ b/lib/efi_loader/efi_disk.c
> @@ -687,6 +687,13 @@ int efi_disk_probe(void *ctx, struct event *event)
>   			return -1;
>   	}
>
> +	/* only do the boot option management when UEFI sub-system is initialized */
> +	if (efi_obj_list_initialized == EFI_SUCCESS) {
> +		ret = efi_bootmgr_update_media_device_boot_option();
> +		if (ret != EFI_SUCCESS && ret != EFI_NOT_FOUND)

efi_bootmgr_update_media_device_boot_option() returns EFI_SUCCESS if
calloc fails(). It fails with EFI_NOT_FOUND if there is no handle with a
simple file protocol.

Why would we return 0 here if we are out of memory?
It would be preferable to let
efi_bootmgr_update_media_device_boot_option() return EFI_SUCCESS if
there is no partition with a file system.

> +			return -1;
> +	}
> +
>   	return 0;
>   }
>
> diff --git a/lib/efi_loader/efi_setup.c b/lib/efi_loader/efi_setup.c
> index 58d4e13402..4686374995 100644
> --- a/lib/efi_loader/efi_setup.c
> +++ b/lib/efi_loader/efi_setup.c
> @@ -245,6 +245,11 @@ efi_status_t efi_init_obj_list(void)
>   	if (ret != EFI_SUCCESS)
>   		goto out;
>
> +	/* update boot option after variable service initialized */
> +	ret = efi_bootmgr_update_media_device_boot_option();
> +	if (ret != EFI_SUCCESS && ret != EFI_NOT_FOUND)
> +		goto out;

Why is a failing calloc() in
efi_bootmgr_update_media_device_boot_option() ok here?

There is a patch missing to fix
efi_bootmgr_update_media_device_boot_option().

Best regards

Heinrich

> +
>   	/* Define supported languages */
>   	ret = efi_init_platform_lang();
>   	if (ret != EFI_SUCCESS)