thr3ads.net - Virtualization - [PATCH v1] virtio-pci: Fix legacy device flag setting error in probe [Jul 2023]

If this information is useful, please help other people find it:
Share via:

Feng Liu

2023-Jul-19 15:45 UTC

[PATCH v1] virtio-pci: Fix legacy device flag setting error in probe

The 'is_legacy' flag is used to differentiate between legacy vs modern
device. Currently, it is based on the value of vp_dev->ldev.ioaddr.
However, due to the shared memory of the union between struct
virtio_pci_legacy_device and struct virtio_pci_modern_device, when
virtio_pci_modern_probe modifies the content of struct
virtio_pci_modern_device, it affects the content of struct
virtio_pci_legacy_device, and ldev.ioaddr is no longer zero, causing
the 'is_legacy' flag to be set as true. To resolve issue, when legacy
device is probed, mark 'is_legacy' as true, when modern device is
probed, keep 'is_legacy' as false.

Fixes: 4f0fc22534e3 ("virtio_pci: Optimize virtio_pci_device structure
size")
Signed-off-by: Feng Liu <feliu at nvidia.com>
Reviewed-by: Parav Pandit <parav at nvidia.com>
Reviewed-by: Jiri Pirko <jiri at nvidia.com>
---
 drivers/virtio/virtio_pci_common.c | 2 --
 drivers/virtio/virtio_pci_legacy.c | 1 +
 2 files changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/virtio/virtio_pci_common.c
b/drivers/virtio/virtio_pci_common.c
index a6c86f916dbd..c2524a7207cf 100644
--- a/drivers/virtio/virtio_pci_common.c
+++ b/drivers/virtio/virtio_pci_common.c
@@ -557,8 +557,6 @@ static int virtio_pci_probe(struct pci_dev *pci_dev,
 
 	pci_set_master(pci_dev);
 
-	vp_dev->is_legacy = vp_dev->ldev.ioaddr ? true : false;
-
 	rc = register_virtio_device(&vp_dev->vdev);
 	reg_dev = vp_dev;
 	if (rc)
diff --git a/drivers/virtio/virtio_pci_legacy.c
b/drivers/virtio/virtio_pci_legacy.c
index 2257f1b3d8ae..d9cbb02b35a1 100644
--- a/drivers/virtio/virtio_pci_legacy.c
+++ b/drivers/virtio/virtio_pci_legacy.c
@@ -223,6 +223,7 @@ int virtio_pci_legacy_probe(struct virtio_pci_device
*vp_dev)
 	vp_dev->config_vector = vp_config_vector;
 	vp_dev->setup_vq = setup_vq;
 	vp_dev->del_vq = del_vq;
+	vp_dev->is_legacy = true;
 
 	return 0;
 }
-- 
2.37.1 (Apple Git-137.1)

Xuan Zhuo

2023-Jul-20 02:06 UTC

head link

[PATCH v1] virtio-pci: Fix legacy device flag setting error in probe

On Wed, 19 Jul 2023 11:45:50 -0400, Feng Liu <feliu at nvidia.com>
wrote:> The 'is_legacy' flag is used to differentiate between legacy vs
modern
> device. Currently, it is based on the value of vp_dev->ldev.ioaddr.
> However, due to the shared memory of the union between struct
> virtio_pci_legacy_device and struct virtio_pci_modern_device, when
> virtio_pci_modern_probe modifies the content of struct
> virtio_pci_modern_device, it affects the content of struct
> virtio_pci_legacy_device, and ldev.ioaddr is no longer zero, causing
> the 'is_legacy' flag to be set as true. To resolve issue, when
legacy
> device is probed, mark 'is_legacy' as true, when modern device is
> probed, keep 'is_legacy' as false.
>
> Fixes: 4f0fc22534e3 ("virtio_pci: Optimize virtio_pci_device structure
size")
> Signed-off-by: Feng Liu <feliu at nvidia.com>
> Reviewed-by: Parav Pandit <parav at nvidia.com>
> Reviewed-by: Jiri Pirko <jiri at nvidia.com>
Reviewed-by: Xuan Zhuo <xuanzhuo at linux.alibaba.com>

> ---
>  drivers/virtio/virtio_pci_common.c | 2 --
>  drivers/virtio/virtio_pci_legacy.c | 1 +
>  2 files changed, 1 insertion(+), 2 deletions(-)
>
> diff --git a/drivers/virtio/virtio_pci_common.c
b/drivers/virtio/virtio_pci_common.c
> index a6c86f916dbd..c2524a7207cf 100644
> --- a/drivers/virtio/virtio_pci_common.c
> +++ b/drivers/virtio/virtio_pci_common.c
> @@ -557,8 +557,6 @@ static int virtio_pci_probe(struct pci_dev *pci_dev,
>
>  	pci_set_master(pci_dev);
>
> -	vp_dev->is_legacy = vp_dev->ldev.ioaddr ? true : false;
> -
>  	rc = register_virtio_device(&vp_dev->vdev);
>  	reg_dev = vp_dev;
>  	if (rc)
> diff --git a/drivers/virtio/virtio_pci_legacy.c
b/drivers/virtio/virtio_pci_legacy.c
> index 2257f1b3d8ae..d9cbb02b35a1 100644
> --- a/drivers/virtio/virtio_pci_legacy.c
> +++ b/drivers/virtio/virtio_pci_legacy.c
> @@ -223,6 +223,7 @@ int virtio_pci_legacy_probe(struct virtio_pci_device
*vp_dev)
>  	vp_dev->config_vector = vp_config_vector;
>  	vp_dev->setup_vq = setup_vq;
>  	vp_dev->del_vq = del_vq;
> +	vp_dev->is_legacy = true;
>
>  	return 0;
>  }
> --
> 2.37.1 (Apple Git-137.1)
>

Jason Wang

2023-Jul-20 02:27 UTC

head link

[PATCH v1] virtio-pci: Fix legacy device flag setting error in probe

On Wed, Jul 19, 2023 at 11:46?PM Feng Liu <feliu at nvidia.com>
wrote:>
> The 'is_legacy' flag is used to differentiate between legacy vs
modern
> device. Currently, it is based on the value of vp_dev->ldev.ioaddr.
> However, due to the shared memory of the union between struct
> virtio_pci_legacy_device and struct virtio_pci_modern_device, when
> virtio_pci_modern_probe modifies the content of struct
> virtio_pci_modern_device, it affects the content of struct
> virtio_pci_legacy_device, and ldev.ioaddr is no longer zero, causing
> the 'is_legacy' flag to be set as true. To resolve issue, when
legacy
> device is probed, mark 'is_legacy' as true, when modern device is
> probed, keep 'is_legacy' as false.
>
> Fixes: 4f0fc22534e3 ("virtio_pci: Optimize virtio_pci_device structure
size")
> Signed-off-by: Feng Liu <feliu at nvidia.com>
> Reviewed-by: Parav Pandit <parav at nvidia.com>
> Reviewed-by: Jiri Pirko <jiri at nvidia.com>
> ---
>  drivers/virtio/virtio_pci_common.c | 2 --
>  drivers/virtio/virtio_pci_legacy.c | 1 +
>  2 files changed, 1 insertion(+), 2 deletions(-)
>
> diff --git a/drivers/virtio/virtio_pci_common.c
b/drivers/virtio/virtio_pci_common.c
> index a6c86f916dbd..c2524a7207cf 100644
> --- a/drivers/virtio/virtio_pci_common.c
> +++ b/drivers/virtio/virtio_pci_common.c
> @@ -557,8 +557,6 @@ static int virtio_pci_probe(struct pci_dev *pci_dev,
>
>         pci_set_master(pci_dev);
>
> -       vp_dev->is_legacy = vp_dev->ldev.ioaddr ? true : false;
> -
>         rc = register_virtio_device(&vp_dev->vdev);
>         reg_dev = vp_dev;
>         if (rc)
> diff --git a/drivers/virtio/virtio_pci_legacy.c
b/drivers/virtio/virtio_pci_legacy.c
> index 2257f1b3d8ae..d9cbb02b35a1 100644
> --- a/drivers/virtio/virtio_pci_legacy.c
> +++ b/drivers/virtio/virtio_pci_legacy.c
> @@ -223,6 +223,7 @@ int virtio_pci_legacy_probe(struct virtio_pci_device
*vp_dev)
>         vp_dev->config_vector = vp_config_vector;
>         vp_dev->setup_vq = setup_vq;
>         vp_dev->del_vq = del_vq;
> +       vp_dev->is_legacy = true;
This seems break force_legacy for modern device:

        if (force_legacy) {
                rc = virtio_pci_legacy_probe(vp_dev);
                /* Also try modern mode if we can't map BAR0 (no IO space).
*/
                if (rc == -ENODEV || rc == -ENOMEM)
                        rc = virtio_pci_modern_probe(vp_dev);

Thanks
>
>         return 0;
>  }
> --
> 2.37.1 (Apple Git-137.1)
>

Virtualization - Jul 2023 - [PATCH v1] virtio-pci: Fix legacy device flag setting error in probe

[PATCH v1] virtio-pci: Fix legacy device flag setting error in probe

[PATCH v1] virtio-pci: Fix legacy device flag setting error in probe

[PATCH v1] virtio-pci: Fix legacy device flag setting error in probe