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

[Borislav Petkov]

On Fri, Apr 23, 2021 at 03:35:30PM -0400, Len Brown wrote:
> Yes.  If a library decides to execute AMX instructions on behalf
> of a task, the kernel will allocate an 8KB context switch buffer
> on behalf of that task.

Again, the library should ask the kernel first whether it supports AMX.
And the process should decide whether to use AMX - not the library on
its own, on behalf of the process.

> Granted, if you find a reason to dislike AMX, the mechanisms to disable
> it today are on a system-wide basis, not on a process or task basis.

Again, I don't dislike the feature. I don't want libraries jumping on
new features without asking the process or the kernel first especially
when those features have performance implications and need kernel
support.

-- 
Regards/Gruss,
    Boris.

https://people.kernel.org/tglx/notes-about-netiquette