Re: [RFC PATCH] vfio/pci: add PCIe TPH to device feature ioctl

[Jason Gunthorpe]

On Wed, Mar 12, 2025 at 07:53:17AM +0000, Tian, Kevin wrote:

> Probably we should not allow device-specific mode unless the user is
> capable of CAP_SYS_RAWIO? It allows an user to pollute caches on
> CPUs which its processes are not affined to, hence could easily break
> SLAs which CSPs try to achieve...

I'm not sure this is within the threat model for VFIO though..

qemu or the operator needs to deal with this by not permiting such
HW to go into a VM.

Really we can't block device specific mode anyhow because we can't
even discover it on the kernel side..

Jason