Jason Wang
2022-Jun-02 07:11 UTC
[PATCH 1/6] vDPA/ifcvf: get_config_size should return a value no greater than dev implementation
On Thu, Jun 2, 2022 at 10:48 AM Zhu Lingshan <lingshan.zhu at intel.com> wrote:> > ifcvf_get_config_size() should return a virtio device type specific value, > however the ret_value should not be greater than the onboard size of > the device implementation. E.g., for virtio_net, config_size should be > the minimum value of sizeof(struct virtio_net_config) and the onboard > cap size. > > Signed-off-by: Zhu Lingshan <lingshan.zhu at intel.com> > --- > drivers/vdpa/ifcvf/ifcvf_base.c | 8 ++++++-- > drivers/vdpa/ifcvf/ifcvf_base.h | 2 ++ > 2 files changed, 8 insertions(+), 2 deletions(-) > > diff --git a/drivers/vdpa/ifcvf/ifcvf_base.c b/drivers/vdpa/ifcvf/ifcvf_base.c > index 48c4dadb0c7c..6bccc8291c26 100644 > --- a/drivers/vdpa/ifcvf/ifcvf_base.c > +++ b/drivers/vdpa/ifcvf/ifcvf_base.c > @@ -128,6 +128,7 @@ int ifcvf_init_hw(struct ifcvf_hw *hw, struct pci_dev *pdev) > break; > case VIRTIO_PCI_CAP_DEVICE_CFG: > hw->dev_cfg = get_cap_addr(hw, &cap); > + hw->cap_dev_config_size = le32_to_cpu(cap.length);One possible issue here is that, if the hardware have more size than spec, we may end up with a migration compatibility issue. It looks to me we'd better build the config size based on the features, e.g it looks to me for net, we should probably use offset_of(struct virtio_net_config, mtu)?> IFCVF_DBG(pdev, "hw->dev_cfg = %p\n", hw->dev_cfg); > break; > } > @@ -233,15 +234,18 @@ int ifcvf_verify_min_features(struct ifcvf_hw *hw, u64 features) > u32 ifcvf_get_config_size(struct ifcvf_hw *hw) > { > struct ifcvf_adapter *adapter; > + u32 net_config_size = sizeof(struct virtio_net_config); > + u32 blk_config_size = sizeof(struct virtio_blk_config); > + u32 cap_size = hw->cap_dev_config_size; > u32 config_size; > > adapter = vf_to_adapter(hw); > switch (hw->dev_type) { > case VIRTIO_ID_NET: > - config_size = sizeof(struct virtio_net_config); > + config_size = cap_size >= net_config_size ? net_config_size : cap_size;I don't get the code here, any chance that net_config_size could be zero? Thanks> break; > case VIRTIO_ID_BLOCK: > - config_size = sizeof(struct virtio_blk_config); > + config_size = cap_size >= blk_config_size ? blk_config_size : cap_size; > break; > default: > config_size = 0; > diff --git a/drivers/vdpa/ifcvf/ifcvf_base.h b/drivers/vdpa/ifcvf/ifcvf_base.h > index 115b61f4924b..f5563f665cc6 100644 > --- a/drivers/vdpa/ifcvf/ifcvf_base.h > +++ b/drivers/vdpa/ifcvf/ifcvf_base.h > @@ -87,6 +87,8 @@ struct ifcvf_hw { > int config_irq; > int vqs_reused_irq; > u16 nr_vring; > + /* VIRTIO_PCI_CAP_DEVICE_CFG size */ > + u32 cap_dev_config_size; > }; > > struct ifcvf_adapter { > -- > 2.31.1 >