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Date:   Tue, 20 Jun 2023 10:09:09 +0200
From:   Borislav Petkov <bp@alien8.de>
To:     Thomas Gleixner <tglx@linutronix.de>
Cc:     Ashok Raj <ashok.raj@intel.com>,
        LKML <linux-kernel@vger.kernel.org>, x86@kernel.org,
        Mario Limonciello <mario.limonciello@amd.com>,
        Tom Lendacky <thomas.lendacky@amd.com>,
        Tony Battersby <tonyb@cybernetics.com>,
        Ashok Raj <ashok.raj@linux.intel.com>,
        Tony Luck <tony.luck@intel.com>,
        Arjan van de Veen <arjan@linux.intel.com>,
        Eric Biederman <ebiederm@xmission.com>
Subject: Re: [patch v3 1/7] x86/smp: Make stop_other_cpus() more robust
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References: <20230615190036.898273129@linutronix.de>
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On Fri, Jun 16, 2023 at 08:01:56PM +0200, Thomas Gleixner wrote:
> From: Thomas Gleixner <tglx@linutronix.de>
> Subject: x86/smp: Make stop_other_cpus() more robust
> Date: Wed, 26 Apr 2023 18:37:00 +0200
> 
> Tony reported intermittent lockups on poweroff. His analysis identified the
> wbinvd() in stop_this_cpu() as the culprit. This was added to ensure that
> on SME enabled machines a kexec() does not leave any stale data in the
> caches when switching from encrypted to non-encrypted mode or vice versa.
> 
> That wbindv() is conditional on the SME feature bit which is read directly

wbinvd()

Otherwise:

Reviewed-by: Borislav Petkov (AMD) <bp@alien8.de>

-- 
Regards/Gruss,
    Boris.

https://people.kernel.org/tglx/notes-about-netiquette