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From:   Thomas Gleixner <tglx@linutronix.de>
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To:     Paul Gortmaker <paul.gortmaker@windriver.com>,
        Peter Zijlstra <peterz@infradead.org>
Cc:     Richard Purdie <richard.purdie@linuxfoundation.org>,
        Borislav Petkov <bp@alien8.de>, x86@kernel.org,
        linux-kernel@vger.kernel.org
Subject: Re: 32 bit qemu regression from v6.5 tip pull [6c480f222128
 x86/alternative: Rewrite optimize_nops() some]
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Date:   Mon, 30 Oct 2023 19:24:27 +0100
Message-ID: <877cn4ynms.ffs@tglx>
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On Mon, Oct 30 2023 at 11:28, Paul Gortmaker wrote:
> [Re: 32 bit qemu regression from v6.5 tip pull [6c480f222128 x86/alternative: Rewrite optimize_nops() some]] On 30/10/2023 (Mon 12:44) Peter Zijlstra wrote:
>
>> Thomas was looking at this and wondered if something like the below
>> would help?
>
> I tested this on a vanilla v6.5.7 baseline, for lack of a better choice
> and got six failures in 136 boots - everything else unchanged - even the
> shell instance that builds the kernel.

While the sync_core() invocation is definitely at the wrong place, I did
not really expect that this cures it.

Can you add "debug-alternative" to the kernel command line and log both
a working and the non-working kernel output. It's noisy :)

Also do you have a .config and the qemu command line handy?

Thanks,

        tglx