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Date: Fri, 31 May 2024 18:54:54 +0200
From: "Arnd Bergmann" <arnd@kernel.org>
To: "Linus Torvalds" <torvalds@linux-foundation.org>,
 "Arnd Bergmann" <arnd@arndb.de>
Cc: "Maciej W. Rozycki" <macro@orcam.me.uk>,
 "Paul E. McKenney" <paulmck@kernel.org>,
 "John Paul Adrian Glaubitz" <glaubitz@physik.fu-berlin.de>,
 linux-alpha@vger.kernel.org,
 "Richard Henderson" <richard.henderson@linaro.org>,
 "Ivan Kokshaysky" <ink@jurassic.park.msu.ru>,
 "Matt Turner" <mattst88@gmail.com>,
 "Alexander Viro" <viro@zeniv.linux.org.uk>, "Marc Zyngier" <maz@kernel.org>,
 linux-kernel@vger.kernel.org, "Michael Cree" <mcree@orcon.net.nz>,
 "Frank Scheiner" <frank.scheiner@web.de>
Subject: Re: [PATCH 00/14] alpha: cleanups for 6.10
Content-Type: text/plain

On Fri, May 31, 2024, at 18:32, Linus Torvalds wrote:
> On Fri, 31 May 2024 at 08:48, Arnd Bergmann <arnd@arndb.de> wrote:
>
> and the solution would be to make a __WRITE_ONCE() that then uses
> "sizeof()" to decide at compile-time whether it can just do it as a
> regular write, or whether it needs to do it as a LL/SC loop.

Just to clarify: I did not mean to suggest we actually
apply the patch from my email or anything close to it, this was
meant as a demonstration for instances that are likely broken but
each one would need to be individually documented if we were to
try to fix them, as Maciej asked about what it would take.

My "alpha: drop pre-EV56 support" actually removed two workarounds
for non-BWX alphas, and neither of them even uses WRITE_ONCE,
so these would also have gone unnoticed by any changes we do
to WRITE_ONCE.

https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/include/linux/?id=a4184174be36369c3af8d937e165f28a43ef1e02

    Arnd