Re: [PATCH] vfio/qat: extend Kconfig dependencies for 420xx and 6xxx devices

[Giovanni Cabiddu <giovanni.cabiddu@intel.com>]

On Mon, Mar 09, 2026 at 05:02:47PM -0600, Alex Williamson wrote:
> On Fri, 13 Feb 2026 09:14:03 +0000
> Suman Kumar Chakraborty <suman.kumar.chakraborty@intel.com> wrote:
> 
> > From: Vijay Sundar Selvamani <vijay.sundar.selvamani@intel.com>
> > 
> > Currently, the QAT VFIO PCI driver can only be configured when the 4xxx
> > QAT driver (CRYPTO_DEV_QAT_4XXX) is enabled. This is too restrictive as
> > the VFIO driver also supports VFs from the 420xx and 6xxx device
> > families, which share a compatible migration interface.
> > 
> > Extends the Kconfig dependencies to allow configuration when any of the
> > supported QAT device families (4xxx, 420xx, or 6xxx) are enabled.
> 
> 420xx seems to be device ID 0x4947:
> 
> drivers/crypto/intel/qat/qat_common/adf_accel_devices.h
> #define PCI_DEVICE_ID_INTEL_QAT_420XXIOV 0x4947
> 
> We don't currently have that in the ID table for the vfio qat driver:
> 
> static const struct pci_device_id qat_vf_vfio_pci_table[] = {
>         /* Intel QAT GEN4 4xxx VF device */
>         { PCI_DRIVER_OVERRIDE_DEVICE_VFIO(PCI_VENDOR_ID_INTEL, 0x4941) },
>         { PCI_DRIVER_OVERRIDE_DEVICE_VFIO(PCI_VENDOR_ID_INTEL, 0x4943) },
>         { PCI_DRIVER_OVERRIDE_DEVICE_VFIO(PCI_VENDOR_ID_INTEL, 0x4945) },
>         /* Intel QAT GEN6 6xxx VF device */
>         { PCI_DRIVER_OVERRIDE_DEVICE_VFIO(PCI_VENDOR_ID_INTEL, 0x4949) },
>         {}
> };
> 
> Are we missing support for this device and is this Kconfig change
> therefore a little overeager?
The PF-side live migration support for the 420xx VF (0x4947) was added
in [1], however the qat_vf_vfio_pci_table in the qat_vfio_pci driver wasn't
updated to include that device. I'm going to send a patch to add that.

Do you prefer both changes (Kconfig and table) on the same patch?

[1] https://lore.kernel.org/all/20251120163023.29288-1-giovanni.cabiddu@intel.com/

Thanks,

-- 
Giovanni