Re: [RFC PATCH v5 1/2] arm64: Introduce stack trace reliability checks in the unwinder

From: Mark Brown <broonie@kernel.org>
To: Mark Rutland <mark.rutland@arm.com>
Cc: madvenka@linux.microsoft.com, jpoimboe@redhat.com,
	ardb@kernel.org, nobuta.keiya@fujitsu.com,
	catalin.marinas@arm.com, will@kernel.org, jmorris@namei.org,
	pasha.tatashin@soleen.com, jthierry@redhat.com,
	linux-arm-kernel@lists.infradead.org,
	live-patching@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [RFC PATCH v5 1/2] arm64: Introduce stack trace reliability checks in the unwinder
Date: Thu, 24 Jun 2021 17:03:31 +0100	[thread overview]
Message-ID: <20210624160331.GD3912@sirena.org.uk> (raw)
In-Reply-To: <20210624144021.GA17937@C02TD0UTHF1T.local>

[-- Attachment #1: Type: text/plain, Size: 819 bytes --]

On Thu, Jun 24, 2021 at 03:40:21PM +0100, Mark Rutland wrote:

> regular unwinds (e.g. so that we can have a backtrace idicate when a
> step is not reliable, like x86 does with '?'), and to do that we need to
> be a little more accurate.

There was the idea that was discussed a bit when I was more actively
working on this of just refactoring our unwinder infrastructure to be a
lot more like the x86 and (IIRC) S/390 in form.  Part of the thing there
was that it'd mean that even where we're not able to actually share code
we'd have more of a common baseline for how things work and what works.
It'd make review, especially cross architecture review, of what's going
on a bit easier too - see some of the concerns Josh had about the
differences here for example.  It'd be a relatively big bit of
refactoring though.

[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 488 bytes --]