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Message-ID: <940596cc-a440-181a-a72a-36282a26dd0a@citrix.com>
Date:   Tue, 7 Mar 2023 18:22:01 +0000
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From:   Andrew Cooper <andrew.cooper3@citrix.com>
Subject: Re: [PATCH] x86/amd: Work around Erratum 1386 - XSAVES malfunction on
 context switch
Content-Language: en-GB
To:     Borislav Petkov <bp@alien8.de>
Cc:     LKML <linux-kernel@vger.kernel.org>,
        Tavis Ormandy <taviso@gmail.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>,
        Dave Hansen <dave.hansen@linux.intel.com>, x86@kernel.org,
        "H. Peter Anvin" <hpa@zytor.com>,
        Alexander Monakov <amonakov@ispras.ru>
References: <Y/W4x7/KFqmDmmR7@thinkstation.cmpxchg8b.net>
 <20230307174643.1240184-1-andrew.cooper3@citrix.com>
 <20230307175050.GCZAd5eu0/Mk2fdLz5@fat_crate.local>
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On 07/03/2023 5:50 pm, Borislav Petkov wrote:
> On Tue, Mar 07, 2023 at 05:46:43PM +0000, Andrew Cooper wrote:
>> +	 * Work around Erratum 1386.  The XSAVES instruction malfunctions in
>> +	 * certain circumstances on Zen1/2 uarch, and not all parts have had
>> +	 * updated microcode at the time of writing (March 2023).
> Any reason for rushing this and not waiting for me to clarify affected
> models first?

Well yes - more and more reports of impacted systems.

Having the full list of affected models is great and all, but how is it
going to change this patch as a workaround ?

~Andrew