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Date:   Thu, 29 Sep 2022 11:57:15 -0300
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Subject: Re: [PATCH] x86/split_lock: Restore warn mode (and add a new one) to
 avoid userspace regression
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To:     Dave Hansen <dave.hansen@intel.com>, tony.luck@intel.com,
        tglx@linutronix.de, linux-kernel@vger.kernel.org, x86@kernel.org
Cc:     mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com,
        hpa@zytor.com, luto@kernel.org, kernel-dev@igalia.com,
        kernel@gpiccoli.net, Fenghua Yu <fenghua.yu@intel.com>,
        Joshua Ashton <joshua@froggi.es>,
        Paul Gofman <pgofman@codeweavers.com>,
        Pavel Machek <pavel@denx.de>,
        Pierre-Loup Griffais <pgriffais@valvesoftware.com>,
        Melissa Wen <mwen@igalia.com>
References: <20220928142109.150263-1-gpiccoli@igalia.com>
 <24f31510-5b33-ada5-9f0e-117420403e8c@intel.com>
From:   "Guilherme G. Piccoli" <gpiccoli@igalia.com>
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On 28/09/2022 18:50, Dave Hansen wrote:
>[...]
> It boils down to either:
>  * The misery is good and we keep it as-is, or
>  * The misery is bad and we kill it
> 
> My gut says we should keep the warnings and kill the misery.  The folks
> who are going to be able to fix the issues are probably also the ones
> looking at dmesg and don't need the extra hint from the misery.  The
> folks running Windows games don't look at dmesg and just want to play
> their game without misery.
> 

Hi Dave, thanks for your response. I really appreciated your reasoning,
and I think it's a good argument. In the end, adding misery would harm
the users that are unlikely to be able to fix (or at least, fix quickly)
the split lock situation, like games or legacy/proprietary code.

I have a revert removing the misery ready and tested, let me know if I
should submit it.

Cheers,


Guilherme