[PATCH v5 12/14] efi_loader: Avoid using sandbox virtio devices

[Heinrich Schuchardt]

On 02.09.24 03:18, Simon Glass wrote:
> While sandbox supports virtio it cannot support actually using the block
> devices to read files, since there is nothing on the other end of the
> 'virtqueue'.
>
> A recent change makes EFI probe all block devices, whether used or not.
> This is apparently required by EFI, although it violates U-Boot's
> lazy-init principle.

We always did this.

What problem do you want to fix? I have not seen any issues in our CI.

>
> We cannot just drop the virtio devices as they are used in sandbox tests.
>
> So for now just add a special case to work around this.
>
> The eventual fix is likely adding an implementation of
> virtio_sandbox_notify() to actually do the block read. That is tracked
> in [1].
>
> Signed-off-by: Simon Glass <sjg at chromium.org>
> Fixes: d5391bf02b9 ("efi_loader: ensure all block devices are probed")
> Reviewed-by: Ilias Apalodimas <ilias.apalodimas at linaro.org>
> [1] https://source.denx.de/u-boot/u-boot/-/issues/37
> ---
>
> (no changes since v3)
>
> Changes in v3:
> - Add a Fixes tag
> - Mention the issue created for this problem
>
>   lib/efi_loader/efi_disk.c | 14 +++++++++++++-
>   1 file changed, 13 insertions(+), 1 deletion(-)
>
> diff --git a/lib/efi_loader/efi_disk.c b/lib/efi_loader/efi_disk.c
> index 93a9a5ac025..2e1d37848fc 100644
> --- a/lib/efi_loader/efi_disk.c
> +++ b/lib/efi_loader/efi_disk.c
> @@ -838,8 +838,20 @@ efi_status_t efi_disk_get_device_name(const efi_handle_t handle, char *buf, int
>   efi_status_t efi_disks_register(void)
>   {
>   	struct udevice *dev;
> +	struct uclass *uc;
>
> -	uclass_foreach_dev_probe(UCLASS_BLK, dev) {
> +	uclass_id_foreach_dev(UCLASS_BLK, dev, uc) {
> +		/*
> +		 * The virtio block-device hangs on sandbox when accessed since
> +		 * there is nothing listening to the mailbox
> +		 */
> +		if (IS_ENABLED(CONFIG_SANDBOX)) {
> +			struct blk_desc *desc = dev_get_uclass_plat(dev);
> +
> +			if (desc->uclass_id == UCLASS_VIRTIO)
> +				continue;
> +		}
> +		device_probe(dev);
>   	}
>
>   	return EFI_SUCCESS;

Please, do not spray sandbox tweaks all over the place.

Can't you just return an error from the sandbox-virtio driver when an
attempt to read a queue is made?

We are using virtio on QEMU. Why do we need sandbox virtio devices? Just
run the relevant tests on the real thing.

Best regards

Heinrich