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Date: Thu, 30 Oct 2025 11:31:38 -0700
From: Andi Kleen <andi@firstfloor.org>
To: Mark Brown <broonie@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>,
	Fangrui Song <maskray@sourceware.org>,
	linux-toolchains@vger.kernel.org, linux-perf-users@vger.kernel.org,
	linux-kernel@vger.kernel.org
Subject: Re: Concerns about SFrame viability for userspace stack walking
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In-Reply-To: <bdda89a7-ff60-46b0-8ce3-28ffec1fac2a@sirena.org.uk>

On Thu, Oct 30, 2025 at 06:07:49PM +0000, Mark Brown wrote:
> On Thu, Oct 30, 2025 at 10:53:13AM -0700, Andi Kleen wrote:
> 
> > IMNSHO the whole sframe effort is misguided because all the major ISAs do have
> > shadow stack hardware support now which is generally a better option. 
> > It would be better to invest effort in deploying that widely.
> 
> It's going to take a *considerable* time for the hardware support to
> become standard.

Optimizing for the past instead of the future?

Not on x86 at least. All my x86 systems have it, except for a few old
skylakes.

-Andi