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

From: Dave Hansen
Date: Fri May 21 2021 - 19:06:09 EST


On 5/21/21 3:07 PM, Len Brown wrote:
> My concern about synchronous allocation is that it will be very easy
> to abuse. programs and threads can ask for buffers they will never
> use. With on-demand allocation, we allocate buffers only if they are
> actually needed.

If someone wants to abuse the on-demand allocation, they will simply
write a single bit to an AMX register. That does *NOT* mean they will
actually execute an instruction that actually uses AMX to do something
meaningful.

In the face of abuse, I think the two approaches are very similar.