Re: Candidate Linux ABI for Intel AMX and hypothetical new related features

On Sun, Mar 28, 2021 at 01:53:15AM +0100, Thomas Gleixner wrote:

Though the little devil in my head tells me, that making AMX support
depend on the CPUID faulting capability might be not the worst thing.

Then we actually enforce CPUID faulting (finally) on CPUs which support
it, which would be a first step into the right direction simply because
then random library X has to go to the kernel and ask for it explicitely
or just shrug and use whatever the kernel is willing to hand out in
CPUID.

Now take that one step further. When the first part of some user space
application asks for it, then you can register that with the process and
make sane decisions for all other requesters which come after it, which
is an important step into the direction of having a common orchestration
for this.

I wrote something like that at least one...

  https://lore.kernel.org/lkml/20190212164833.GK32494@hirez.programming.kicks-ass.net/ (local)

we just need to make sure AMD implements that before it ships a chip
with AVX512 on.