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Message-ID: <e121e972-7689-b2f3-5919-746e3a90cb36@intel.com>
Date:   Wed, 16 Mar 2022 08:47:23 -0700
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To:     Jethro Beekman <jethro@fortanix.com>,
        Cathy Zhang <cathy.zhang@intel.com>, linux-sgx@vger.kernel.org,
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Cc:     ashok.raj@intel.com
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From:   Dave Hansen <dave.hansen@intel.com>
Subject: Re: [RFC PATCH v2 09/10] x86/cpu: Call ENCLS[EUPDATESVN] procedure in
 microcode update
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On 3/16/22 03:24, Jethro Beekman wrote:
>> Doing this automatically and unconditionally during a microcode
>> update seems undesirable. This requires the userland tooling that
>> is coordinating the microcode update to be aware of any SGX
>> enclaves that are running and possibly coordinate sequencing with
>> the processes containing those enclaves. This coupling does not
>> exist today.
> Also, a microcode update may not affect SGX security at all and doing
> the EUPDATESVN procedure may not be required for this particular
> update. This case is called out specifically in the EUPDATESVN
> documentation.

I don't think Intel provides the metadata for the kernel to tell if an
update requires an EUPDATESVN procedure or not.  If this is inconvenient
for you, I'd suggest reporting this to the folks at Intel who can fix
it.  It doesn't seem like something which they are motivated to fix.