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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]
In-Reply-To: <877cn4ynms.ffs@tglx>
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 <ZT/Lmj3xAdwvLE7R@windriver.com> <877cn4ynms.ffs@tglx>
Date:   Mon, 30 Oct 2023 20:30:20 +0100
Message-ID: <871qdbzz5f.ffs@tglx>
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On Mon, Oct 30 2023 at 19:24, Thomas Gleixner wrote:
> 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?

Forgot to ask: Does the probkem persist with 6.6 ?

Thanks,

        tglx