2023-06-02 07:48:26

by Angus Chen

[permalink] [raw]
Subject: [PATCH] vp_vdpa: Check queue number of vdpa device from add_config

When add virtio_pci vdpa device,check the vqs number of device cap
and max_vq_pairs from add_config.

Signed-off-by: Angus Chen <[email protected]>
---
drivers/vdpa/virtio_pci/vp_vdpa.c | 11 +++++++++--
1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/drivers/vdpa/virtio_pci/vp_vdpa.c b/drivers/vdpa/virtio_pci/vp_vdpa.c
index 281287fae89f..4bf1ab637d32 100644
--- a/drivers/vdpa/virtio_pci/vp_vdpa.c
+++ b/drivers/vdpa/virtio_pci/vp_vdpa.c
@@ -478,7 +478,7 @@ static int vp_vdpa_dev_add(struct vdpa_mgmt_dev *v_mdev, const char *name,
struct device *dev = &pdev->dev;
struct vp_vdpa *vp_vdpa = NULL;
u64 device_features;
- int ret, i;
+ int ret, i, queues;

vp_vdpa = vdpa_alloc_device(struct vp_vdpa, vdpa,
dev, &vp_vdpa_ops, 1, 1, name, false);
@@ -491,7 +491,14 @@ static int vp_vdpa_dev_add(struct vdpa_mgmt_dev *v_mdev, const char *name,
vp_vdpa_mgtdev->vp_vdpa = vp_vdpa;

vp_vdpa->vdpa.dma_dev = &pdev->dev;
- vp_vdpa->queues = vp_modern_get_num_queues(mdev);
+ queues = vp_modern_get_num_queues(mdev);
+ if (add_config->mask & BIT_ULL(VDPA_ATTR_DEV_NET_CFG_MAX_VQP)) {
+ if (add_config->net.max_vq_pairs > queues / 2)
+ return -EINVAL;
+ queues = min_t(u32, queues, 2 * add_config->net.max_vq_pairs);
+ }
+
+ vp_vdpa->queues = queues;
vp_vdpa->mdev = mdev;

device_features = vp_modern_get_features(mdev);
--
2.25.1



2023-06-05 07:08:57

by Jason Wang

[permalink] [raw]
Subject: Re: [PATCH] vp_vdpa: Check queue number of vdpa device from add_config

On Fri, Jun 2, 2023 at 3:35 PM Angus Chen <[email protected]> wrote:
>
> When add virtio_pci vdpa device,check the vqs number of device cap
> and max_vq_pairs from add_config.
>
> Signed-off-by: Angus Chen <[email protected]>
> ---
> drivers/vdpa/virtio_pci/vp_vdpa.c | 11 +++++++++--
> 1 file changed, 9 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/vdpa/virtio_pci/vp_vdpa.c b/drivers/vdpa/virtio_pci/vp_vdpa.c
> index 281287fae89f..4bf1ab637d32 100644
> --- a/drivers/vdpa/virtio_pci/vp_vdpa.c
> +++ b/drivers/vdpa/virtio_pci/vp_vdpa.c
> @@ -478,7 +478,7 @@ static int vp_vdpa_dev_add(struct vdpa_mgmt_dev *v_mdev, const char *name,
> struct device *dev = &pdev->dev;
> struct vp_vdpa *vp_vdpa = NULL;
> u64 device_features;
> - int ret, i;
> + int ret, i, queues;
>
> vp_vdpa = vdpa_alloc_device(struct vp_vdpa, vdpa,
> dev, &vp_vdpa_ops, 1, 1, name, false);
> @@ -491,7 +491,14 @@ static int vp_vdpa_dev_add(struct vdpa_mgmt_dev *v_mdev, const char *name,
> vp_vdpa_mgtdev->vp_vdpa = vp_vdpa;
>
> vp_vdpa->vdpa.dma_dev = &pdev->dev;
> - vp_vdpa->queues = vp_modern_get_num_queues(mdev);
> + queues = vp_modern_get_num_queues(mdev);
> + if (add_config->mask & BIT_ULL(VDPA_ATTR_DEV_NET_CFG_MAX_VQP)) {
> + if (add_config->net.max_vq_pairs > queues / 2)
> + return -EINVAL;
> + queues = min_t(u32, queues, 2 * add_config->net.max_vq_pairs);

Looks like you want to mediate the max_vqp here, but what happens:

1) harware have 4 queue paris
2) vp_vdpa cap it into 2 queue pairs
3) guest may still try to enable 4 queue paris

For 3), the kernel needs to mediate the control virtqueue which seems not easy.

How about simply starting from failing if the provisioned #qp is not
equal to the one that hardware has?

Thanks

> + }
> +
> + vp_vdpa->queues = queues;
> vp_vdpa->mdev = mdev;
>
> device_features = vp_modern_get_features(mdev);
> --
> 2.25.1
>


2023-06-06 06:33:56

by Angus Chen

[permalink] [raw]
Subject: RE: [PATCH] vp_vdpa: Check queue number of vdpa device from add_config

Hi,Jason.

> -----Original Message-----
> From: Jason Wang <[email protected]>
> Sent: Monday, June 5, 2023 2:54 PM
> To: Angus Chen <[email protected]>
> Cc: [email protected]; [email protected];
> [email protected]
> Subject: Re: [PATCH] vp_vdpa: Check queue number of vdpa device from
> add_config
>
> On Fri, Jun 2, 2023 at 3:35 PM Angus Chen <[email protected]>
> wrote:
> >
> > When add virtio_pci vdpa device,check the vqs number of device cap
> > and max_vq_pairs from add_config.
> >
> > Signed-off-by: Angus Chen <[email protected]>
> > ---
> > drivers/vdpa/virtio_pci/vp_vdpa.c | 11 +++++++++--
> > 1 file changed, 9 insertions(+), 2 deletions(-)
> >
> > diff --git a/drivers/vdpa/virtio_pci/vp_vdpa.c
> b/drivers/vdpa/virtio_pci/vp_vdpa.c
> > index 281287fae89f..4bf1ab637d32 100644
> > --- a/drivers/vdpa/virtio_pci/vp_vdpa.c
> > +++ b/drivers/vdpa/virtio_pci/vp_vdpa.c
> > @@ -478,7 +478,7 @@ static int vp_vdpa_dev_add(struct vdpa_mgmt_dev
> *v_mdev, const char *name,
> > struct device *dev = &pdev->dev;
> > struct vp_vdpa *vp_vdpa = NULL;
> > u64 device_features;
> > - int ret, i;
> > + int ret, i, queues;
> >
> > vp_vdpa = vdpa_alloc_device(struct vp_vdpa, vdpa,
> > dev, &vp_vdpa_ops, 1, 1, name,
> false);
> > @@ -491,7 +491,14 @@ static int vp_vdpa_dev_add(struct vdpa_mgmt_dev
> *v_mdev, const char *name,
> > vp_vdpa_mgtdev->vp_vdpa = vp_vdpa;
> >
> > vp_vdpa->vdpa.dma_dev = &pdev->dev;
> > - vp_vdpa->queues = vp_modern_get_num_queues(mdev);
> > + queues = vp_modern_get_num_queues(mdev);
> > + if (add_config->mask &
> BIT_ULL(VDPA_ATTR_DEV_NET_CFG_MAX_VQP)) {
> > + if (add_config->net.max_vq_pairs > queues / 2)
> > + return -EINVAL;
> > + queues = min_t(u32, queues, 2 *
> add_config->net.max_vq_pairs);
>
> Looks like you want to mediate the max_vqp here, but what happens:
>
> 1) harware have 4 queue paris
> 2) vp_vdpa cap it into 2 queue pairs
> 3) guest may still try to enable 4 queue paris
>
Yes,you are right,this situation can occur.
> For 3), the kernel needs to mediate the control virtqueue which seems not
> easy.
>
> How about simply starting from failing if the provisioned #qp is not
> equal to the one that hardware has?
Ok,You mean we just check it in vp_vdpa or check it in all other vdpa net drivers?
>
> Thanks
>
> > + }
> > +
> > + vp_vdpa->queues = queues;
> > vp_vdpa->mdev = mdev;
> >
> > device_features = vp_modern_get_features(mdev);
> > --
> > 2.25.1
> >

2023-06-07 03:27:45

by Jason Wang

[permalink] [raw]
Subject: Re: [PATCH] vp_vdpa: Check queue number of vdpa device from add_config

On Tue, Jun 6, 2023 at 2:19 PM Angus Chen <[email protected]> wrote:
>
> Hi,Jason.
>
> > -----Original Message-----
> > From: Jason Wang <[email protected]>
> > Sent: Monday, June 5, 2023 2:54 PM
> > To: Angus Chen <[email protected]>
> > Cc: [email protected]; [email protected];
> > [email protected]
> > Subject: Re: [PATCH] vp_vdpa: Check queue number of vdpa device from
> > add_config
> >
> > On Fri, Jun 2, 2023 at 3:35 PM Angus Chen <[email protected]>
> > wrote:
> > >
> > > When add virtio_pci vdpa device,check the vqs number of device cap
> > > and max_vq_pairs from add_config.
> > >
> > > Signed-off-by: Angus Chen <[email protected]>
> > > ---
> > > drivers/vdpa/virtio_pci/vp_vdpa.c | 11 +++++++++--
> > > 1 file changed, 9 insertions(+), 2 deletions(-)
> > >
> > > diff --git a/drivers/vdpa/virtio_pci/vp_vdpa.c
> > b/drivers/vdpa/virtio_pci/vp_vdpa.c
> > > index 281287fae89f..4bf1ab637d32 100644
> > > --- a/drivers/vdpa/virtio_pci/vp_vdpa.c
> > > +++ b/drivers/vdpa/virtio_pci/vp_vdpa.c
> > > @@ -478,7 +478,7 @@ static int vp_vdpa_dev_add(struct vdpa_mgmt_dev
> > *v_mdev, const char *name,
> > > struct device *dev = &pdev->dev;
> > > struct vp_vdpa *vp_vdpa = NULL;
> > > u64 device_features;
> > > - int ret, i;
> > > + int ret, i, queues;
> > >
> > > vp_vdpa = vdpa_alloc_device(struct vp_vdpa, vdpa,
> > > dev, &vp_vdpa_ops, 1, 1, name,
> > false);
> > > @@ -491,7 +491,14 @@ static int vp_vdpa_dev_add(struct vdpa_mgmt_dev
> > *v_mdev, const char *name,
> > > vp_vdpa_mgtdev->vp_vdpa = vp_vdpa;
> > >
> > > vp_vdpa->vdpa.dma_dev = &pdev->dev;
> > > - vp_vdpa->queues = vp_modern_get_num_queues(mdev);
> > > + queues = vp_modern_get_num_queues(mdev);
> > > + if (add_config->mask &
> > BIT_ULL(VDPA_ATTR_DEV_NET_CFG_MAX_VQP)) {
> > > + if (add_config->net.max_vq_pairs > queues / 2)
> > > + return -EINVAL;
> > > + queues = min_t(u32, queues, 2 *
> > add_config->net.max_vq_pairs);
> >
> > Looks like you want to mediate the max_vqp here, but what happens:
> >
> > 1) harware have 4 queue paris
> > 2) vp_vdpa cap it into 2 queue pairs
> > 3) guest may still try to enable 4 queue paris
> >
> Yes,you are right,this situation can occur.
> > For 3), the kernel needs to mediate the control virtqueue which seems not
> > easy.
> >
> > How about simply starting from failing if the provisioned #qp is not
> > equal to the one that hardware has?
> Ok,You mean we just check it in vp_vdpa or check it in all other vdpa net drivers?

vp_vdpa only, since in some other kind of parents, #qps could be provisioned.

Thanks

> >
> > Thanks
> >
> > > + }
> > > +
> > > + vp_vdpa->queues = queues;
> > > vp_vdpa->mdev = mdev;
> > >
> > > device_features = vp_modern_get_features(mdev);
> > > --
> > > 2.25.1
> > >
>