[Xen-devel] PCIe IOMMU ACS support

[Roman Shaposhnik <roman@xxxxxxxxxx>]

Hi!

I was going through how Xen support PCIe IOMMU ACS and
all I could find is this:
    
https://github.com/xen-project/xen/blob/master/xen/drivers/passthrough/pci.c#L608
which looks to me as an attempt of enabling ACS opportunistically,
but still proceeding forward even if it fails.

Am I missing something here? IOW, does Xen try to do any kind of
fine grained ACS differentiation along the lines of what linux kernel
is doing:
    
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/drivers/pci/quirks.c#n4299

Thanks,
Roman.