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Sender: Ingo Molnar <mingo.kernel.org@gmail.com>
Date:   Mon, 9 Oct 2023 13:42:35 +0200
From:   Ingo Molnar <mingo@kernel.org>
To:     Uros Bizjak <ubizjak@gmail.com>
Cc:     Linus Torvalds <torvalds@linux-foundation.org>, x86@kernel.org,
        linux-kernel@vger.kernel.org, Andy Lutomirski <luto@kernel.org>,
        Nadav Amit <namit@vmware.com>, Brian Gerst <brgerst@gmail.com>,
        Denys Vlasenko <dvlasenk@redhat.com>,
        "H . Peter Anvin" <hpa@zytor.com>,
        Peter Zijlstra <peterz@infradead.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        Borislav Petkov <bp@alien8.de>,
        Josh Poimboeuf <jpoimboe@redhat.com>
Subject: Re: [PATCH 4/4] x86/percpu: Use C for percpu read/write accessors
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* Uros Bizjak <ubizjak@gmail.com> wrote:

> I have tried the trick with all reads volatile (and writes as they were 
> before the patch), but it didn't make a difference. Also, the kernel from 
> the git/tip branch works OK for default config, so I think there is some 
> config option that somehow disturbs the named-as enabled kernel.

Yeah, I made sure tip:x86/percpu boots & works fine on a number of systems 
- but that testing wasn't comprehensive at all, and I didn't have KASAN 
enabled either, which generates pretty intrusive instrumentation.

Thanks,

	Ingo