[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [Xen-devel] [PATCH for-4.12] arm/p2m: do not invalidate p2m root if it is shared with IOMMU

On 29.01.19 15:53, Julien Grall wrote:
Which proprietary kernel driver? And in which context are Set/Way operations 
I would not name it, it is proprietary ;) But we can't live without it.

Using Set/Way is fundamentally broken partly because it does not deal with 
system caches.
I already know it. I've looked at KVM presentation from 2015, your last year 
video from China, reading through ARM ARM.

It also only applies to a given cache and the behavior will not be replicated 
to other CPUs.
In our case cpu cache flushing by Set/Way it is propagated to all cpus with 
`on_each_cpu()`. (Here should be a facepalm emoji)

Running such software is a call for nasty behavior in your guest.
I do understand that.
But we have to handle that. And it is a question to us how to do that.

Andrii Anisov.

Xen-devel mailing list



Lists.xenproject.org is hosted with RackSpace, monitoring our
servers 24x7x365 and backed by RackSpace's Fanatical Support®.