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Date:   Fri, 29 Jul 2022 12:08:38 -0700
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Subject: Re: [PATCH v1 1/2] x86/sev: Use per-CPU PSC structure in prep for
 unaccepted memory support
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To:     Tom Lendacky <thomas.lendacky@amd.com>,
        linux-kernel@vger.kernel.org, x86@kernel.org
Cc:     Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
        Dave Hansen <dave.hansen@linux.intel.com>,
        "Kirill A. Shutemov" <kirill@shutemov.name>,
        "H. Peter Anvin" <hpa@zytor.com>,
        Michael Roth <michael.roth@amd.com>,
        Joerg Roedel <jroedel@suse.de>,
        Andy Lutomirski <luto@kernel.org>,
        Peter Zijlstra <peterz@infradead.org>
References: <20220614120231.48165-1-kirill.shutemov@linux.intel.com>
 <cover.1659103274.git.thomas.lendacky@amd.com>
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From:   Dave Hansen <dave.hansen@intel.com>
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On 7/29/22 07:25, Tom Lendacky wrote:
>> Considering that runtime acceptance is already single-threaded[1] *and*
>> there's a fallback method, why not just have a single copy of this
>> guarded by a single lock?
> 
> This function is called for more than just memory acceptance. It's also
> called for any changes from or to private or shared, which isn't
> single-threaded.

I think this tidbit from the changelog threw me off:

> Protect the use of the per-CPU structure by disabling interrupts during
> memory acceptance.

Could you please revise that to accurately capture the impact of this
change?