Re: [PATCH] pci: Add a acs_disable option for pci kernel parameter

[Stephen Bates]

>> This patch adds a new boot option to the pci kernel parameter called
>> "acs_disable" that will disable ACS. This is useful for PCI peer to
>> peer communication but can cause problems when IOVA isolation is
>> required and an IOMMU is enabled. Use with care.

> Eww.

Thanks for the feedback Christoph. My sentiments exactly ;-).  

> Can we please add smbios quirks for the systems where you've
> observed this? 

I can look at doing this. The issue with this approach is that it will require a kernel patch for each new system that is detected.

> we probably also want to keep the option just in case).

Agreed. At least then operators have a path to ACS disable prior to a quirk being accepted.

Stephen