Re: [RFC PATCH] rseq: x86: implement abort-at-ip extension

From: Florian Weimer
Date: Wed Jan 12 2022 - 11:00:57 EST


* Peter Zijlstra:

> On Wed, Jan 12, 2022 at 04:16:36PM +0100, Florian Weimer wrote:
>
>> You could perhaps push a signal frame onto the stack. It's going to
>> be expensive, but it's already in the context switch path, so maybe it
>> does not matter.
>
> Please no! Signals are a trainwreck that need change (see the whole
> AVX-512 / AMX saga), we shouldn't use more of that just cause.

If it's a signal, it should be modeled as such. I think it's pretty
close to a synchronous signal.