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

- From: Greg KH \<gregkh@linuxfoundation.org\>
- Date: 2021-03-27 09:59:35 
- List: linux-api
- Page: https://ratatoskr.run/linux-api/2021/03/6317539
- Thread: https://ratatoskr.run/linux-api/2021/03/6317344/t.md

```text
On Fri, Mar 26, 2021 at 11:39:18PM -0400, Len Brown wrote:
> Hi Andy,
> 
> Say a mainline links with a math library that uses AMX without the
> knowledge of the mainline.

What does this mean?  What happened to the context here?

> Say the mainline is also linked with a userspace threading library
> that thinks it has a concept of XSAVE area size.

How can the kernel (what I think you mean by "mainline" here) be linked
with a userspace library at all?

> Wouldn't the change in XCR0, resulting in XSAVE size change, risk
> confusing the threading library?

Shouldn't that be the job of the kernel and not userspace?

totally confused,

greg k-h
```