Re: [PATCH v4 06/17] PCI: add SIOV and IMS capability detection

[Jason Gunthorpe]

On Fri, Nov 13, 2020 at 02:42:02AM +0000, Tian, Kevin wrote:

> CPUID#1_ECX is a x86 thing. Do we need to figure out probably_on_
> bare_metal for every architecture altogether, or is it OK to just
> handle it for x86 arch at this stage? Based on previous discussions 
> ims is just one piece of multiple technologies to enable SIOV-like
> scalability. Ideally arch-specific enablement beyond ims (e.g. the 
> IOMMU part) will be required for such scaled usage thus we 
> may just leave ims disabled for non-x86 and wait until that time to 
> figure out arch specific probably_on_bare_metal?

At the very least you need to ensure that
pci_subdevice_msi_create_irq_domain() fails entirely on other
architectures until they can sort out these sorts of issues..

Jason