[PATCH 2/2] efi: remove error in efi_disk_remove

[Heinrich Schuchardt]

On 3/8/23 14:26, Patrick Delaunay wrote:
> EFI has no reason to block the driver remove when the associated EFI
> resources failed to be released.
>
> This patch avoids DM issue when an EFI resource can't be released,
> for example if this resource wasn't created, for duplicated device name
> (error EFI_ALREADY_STARTED).
>
> Without this patch, the U-Boot device tree is not updated for "usb stop"
> command because EFI stack can't free a resource; in usb_stop(), the
> remove operation is stopped on first device_remove() error, including a
> device_notify() error on any chil
The typical reason to return an error here is that the EFI device is
still in use, i.e. a protocol installed on the EFI handle is opened by a
child controller or driver. As long as the EFI handle cannot be removed
we must not remove the linked DM device or we corrupt our data model.

Best regards

Heinrich

>
> And this remove error, returned by usb_stop(), is not managed in cmd/usb.c
> and the next "usb start" command cause a crash because all the USB devices
> need to be released before the next USB scan.
>
> Signed-off-by: Patrick Delaunay <patrick.delaunay at foss.st.com>
> ---
>
>   lib/efi_loader/efi_disk.c | 12 ++++++++----
>   1 file changed, 8 insertions(+), 4 deletions(-)
>
> diff --git a/lib/efi_loader/efi_disk.c b/lib/efi_loader/efi_disk.c
> index 8d53ba3bd27e..22a0035dcde2 100644
> --- a/lib/efi_loader/efi_disk.c
> +++ b/lib/efi_loader/efi_disk.c
> @@ -767,16 +767,20 @@ int efi_disk_remove(void *ctx, struct event *event)
>   {
>   	enum uclass_id id;
>   	struct udevice *dev;
> +	int ret = 0;
>
>   	dev = event->data.dm.dev;
>   	id = device_get_uclass_id(dev);
>
>   	if (id == UCLASS_BLK)
> -		return efi_disk_delete_raw(dev);
> +		ret = efi_disk_delete_raw(dev);
>   	else if (id == UCLASS_PARTITION)
> -		return efi_disk_delete_part(dev);
> -	else
> -		return 0;
> +		ret = efi_disk_delete_part(dev);
> +
> +	if (ret)
> +		log_err("%s failed for %s uclass %u (%d)\n", __func__, dev->name, id, ret);
> +
> +	return 0;
>   }
>
>   /**