[PATCH v2] virtio: fix boot device hunting in qemu with virtio

[PATCH v2] virtio: fix boot device hunting in qemu with virtio

[Ludwig Nussel]

Commit 70101c3217ae ("virtio: mmio: Return error codes on probe
failures") returns -ENODEV where it would return 0 before. That path is
apparently hit in qemu and breaks boot device discovery
(virtio_bootdev_hunt() expects only ENOENT). So return -ENOENT in
that path instead.
The remaining two error returns in the function are untouched as I
don't know where they play a role.

Signed-off-by: Ludwig Nussel <ludwig.nussel@siemens.com>

---

Changes in v2:
 - return ENOENT in probe()

 drivers/virtio/virtio_mmio.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/virtio/virtio_mmio.c b/drivers/virtio/virtio_mmio.c
index 62afe609ec0..d90d8309f99 100644
--- a/drivers/virtio/virtio_mmio.c
+++ b/drivers/virtio/virtio_mmio.c
@@ -372,7 +372,7 @@ static int virtio_mmio_probe(struct udevice *udev)
 		 * virtio-mmio device with an ID 0 is a (dummy) placeholder
 		 * with no function. End probing now with no error reported.
 		 */
-		return -ENODEV;
+		return -ENOENT;
 	}
 	uc_priv->vendor = readl(priv->base + VIRTIO_MMIO_VENDOR_ID);
 
-- 
2.43.0

base-commit: 4433253ecf2041f9362a763bb6cb79960921ac7e
branch: us-virtio2

Re: [PATCH v2] virtio: fix boot device hunting in qemu with virtio

[Simon Glass]

On Mon, 4 May 2026 at 01:11, Ludwig Nussel <ludwig.nussel@siemens.com> wrote:
>
> Commit 70101c3217ae ("virtio: mmio: Return error codes on probe
> failures") returns -ENODEV where it would return 0 before. That path is
> apparently hit in qemu and breaks boot device discovery
> (virtio_bootdev_hunt() expects only ENOENT). So return -ENOENT in
> that path instead.
> The remaining two error returns in the function are untouched as I
> don't know where they play a role.
>
> Signed-off-by: Ludwig Nussel <ludwig.nussel@siemens.com>
>
> ---
>
> Changes in v2:
>  - return ENOENT in probe()
>
>  drivers/virtio/virtio_mmio.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>

Reviewed-by: Simon Glass <sjg@chromium.org>

Re: [PATCH v2] virtio: fix boot device hunting in qemu with virtio

[Kuan-Wei Chiu]

On Mon, May 04, 2026 at 09:10:23AM +0200, Ludwig Nussel wrote:
> Commit 70101c3217ae ("virtio: mmio: Return error codes on probe
> failures") returns -ENODEV where it would return 0 before. That path is
> apparently hit in qemu and breaks boot device discovery
> (virtio_bootdev_hunt() expects only ENOENT). So return -ENOENT in
> that path instead.
> The remaining two error returns in the function are untouched as I
> don't know where they play a role.
> 
> Signed-off-by: Ludwig Nussel <ludwig.nussel@siemens.com>

Acked-by: Kuan-Wei Chiu <visitorckw@gmail.com>

Regards,
Kuan-Wei

> 
> ---
> 
> Changes in v2:
>  - return ENOENT in probe()
> 
>  drivers/virtio/virtio_mmio.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/virtio/virtio_mmio.c b/drivers/virtio/virtio_mmio.c
> index 62afe609ec0..d90d8309f99 100644
> --- a/drivers/virtio/virtio_mmio.c
> +++ b/drivers/virtio/virtio_mmio.c
> @@ -372,7 +372,7 @@ static int virtio_mmio_probe(struct udevice *udev)
>  		 * virtio-mmio device with an ID 0 is a (dummy) placeholder
>  		 * with no function. End probing now with no error reported.
>  		 */
> -		return -ENODEV;
> +		return -ENOENT;
>  	}
>  	uc_priv->vendor = readl(priv->base + VIRTIO_MMIO_VENDOR_ID);
>  
> -- 
> 2.43.0
> 
> base-commit: 4433253ecf2041f9362a763bb6cb79960921ac7e
> branch: us-virtio2

Re: [PATCH v2] virtio: fix boot device hunting in qemu with virtio

[Tom Rini]

On Mon, 04 May 2026 09:10:23 +0200, Ludwig Nussel wrote:

> Commit 70101c3217ae ("virtio: mmio: Return error codes on probe
> failures") returns -ENODEV where it would return 0 before. That path is
> apparently hit in qemu and breaks boot device discovery
> (virtio_bootdev_hunt() expects only ENOENT). So return -ENOENT in
> that path instead.
> The remaining two error returns in the function are untouched as I
> don't know where they play a role.
> 
> [...]

Applied to u-boot/master, thanks!

[1/1] virtio: fix boot device hunting in qemu with virtio
      commit: 18806dae0e6fa9e0912a258e15f61b1b346dfdbc
-- 
Tom