linux-kernel - Re: [PATCH 0/4] selftests/sgx: Harden test enclave

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Message-ID: <707e662f-5aed-ef86-a2e3-dda3959d6f7d@cs.kuleuven.be>
Date:   Mon, 24 Jul 2023 12:46:01 +0200
From:   Jo Van Bulck <jo.vanbulck@...kuleuven.be>
To:     Jarkko Sakkinen <jarkko@...nel.org>, linux-sgx@...r.kernel.org,
        linux-kernel@...r.kernel.org
Cc:     dave.hansen@...ux.intel.com
Subject: Re: [PATCH 0/4] selftests/sgx: Harden test enclave

On 22.07.23 20:10, Jarkko Sakkinen wrote:
> This code is not meant for production. I implemented it specifically for
> kselftest, and that is exactly its scope.

I see, makes sense. As per Dave's suggestion, I'll see if I can submit a 
proposed minimal patch to remove any existing sanitization code that is 
not necessary for kselftest (eg register cleansing) and avoid any 
misguided impressions of the test enclave being representative.

> I'm not sure what is "correct" behavior in the context of a kselftest
> instance.

True. But at least when defining "correct" as passing the selftests, 
then I think it makes sense to merge the compiler optimization fixes. As 
the existing code clearly emits wrong assembly that breaks the selftests 
when switching optimization levels (which may always also be 
incorporated by default in future gcc versions or other compilers like 
clang).

Thus, I'll separate this out and submit another patch to ensure 
correctness with compiler optimizations only.

Best,
Jo