[PATCH 4/4] eal: add new args to choose VFIO mode

[Xing, Beilei]

> -----Original Message-----
> From: Stephen Hemminger <stephen at networkplumber.org>
> Sent: Saturday, December 23, 2023 1:18 AM
> To: Xing, Beilei <beilei.xing at intel.com>
> Cc: Burakov, Anatoly <anatoly.burakov at intel.com>; dev at dpdk.org;
> thomas at monjalon.net; ferruh.yigit at amd.com; Richardson, Bruce
> <bruce.richardson at intel.com>; chenbox at nvidia.com; Cao, Yahui
> <yahui.cao at intel.com>
> Subject: Re: [PATCH 4/4] eal: add new args to choose VFIO mode
> 
> On Fri, 22 Dec 2023 19:44:53 +0000
> beilei.xing at intel.com wrote:
> 
> > From: Beilei Xing <beilei.xing at intel.com>
> >
> > Since now Linux has both of VFIO Container/GROUP & VFIO IOMMUFD/CDEV
> > support, user can determine how to probe the PCI device by the new
> > args "--vfio-mode".
> >
> > Use "--vfio-mode=container" to choose VFIO Container/GROUP, and use
> > "--vfio-mode=iommufd" to choose VFIO IOMMUFD/CDEV.
> >
> > Signed-off-by: Beilei Xing <beilei.xing at intel.com>
> > Signed-off-by: Yahui Cao <yahui.cao at intel.com>
> 
> Can't this be automatic, users don't need more EAL options.

Thanks for your review. Since Linux supports both VFIO Container/GROUP and VFIO
OMMUFD/CDEV currently, I think user can choose which mode they want. The new
IOMMU features (e.g. PASID/SSID) may be only available through VFIO IOMMUFD/CDEV
interface, VFIO Container/GROUP may be deprecated in future, and then DPDK will
use iommufd mode automatically.
.