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Subject: Re: [PATCH v29 00/20] Intel SGX foundations
To:     "Dr. Greg" <greg@enjellic.com>
Cc:     Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>,
        linux-kernel@vger.kernel.org, x86@kernel.org,
        linux-sgx@vger.kernel.org, akpm@linux-foundation.org,
        dave.hansen@intel.com, sean.j.christopherson@intel.com,
        nhorman@redhat.com, npmccallum@redhat.com, haitao.huang@intel.com,
        andriy.shevchenko@linux.intel.com, tglx@linutronix.de,
        kai.svahn@intel.com, bp@alien8.de, josh@joshtriplett.org,
        luto@kernel.org, kai.huang@intel.com, rientjes@google.com,
        cedric.xing@intel.com, puiterwijk@redhat.com
References: <20200421215316.56503-1-jarkko.sakkinen@linux.intel.com>
 <e50f4c00-12e6-19e6-ead3-f180074bceea@linux.microsoft.com>
 <20200507180654.GA17632@wind.enjellic.com>
From:   Jordan Hand <jorhand@linux.microsoft.com>
Message-ID: <97a7a73b-53ea-d4f8-5323-f9f109150480@linux.microsoft.com>
Date:   Fri, 8 May 2020 09:16:20 -0700
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On 5/7/20 11:06 AM, Dr. Greg wrote:
> On Wed, May 06, 2020 at 09:39:55AM -0700, Jordan Hand wrote:
> 
> Good afternoon, I hope the week is going well for everyone.
> 
>> On 4/21/20 2:52 PM, Jarkko Sakkinen wrote:
>>> Make the vDSO callable directly from C by preserving RBX and taking leaf
>>>    from RCX.
> 
>> Tested with the Open Enclave SDK on top of Intel PSW. Specifically built
>> the Intel PSW with changes to support /dev/sgx mapping[1] new in v29.
>>
>> Tested-by: Jordan Hand <jorhand@linux.microsoft.com>
>>
>> [1] https://github.com/intel/linux-sgx/pull/530
> 
> Did you re-wire your SDK to convert all your ECALL and exception
> handling to the new VDSO architecture?
 >

No. We have many users of our SDK who rely on the out-of-tree driver and 
will for the foreseeable future. I aim to support both in-tree and 
out-of-tree with minimal code diff.

>
> Failures in enclave loading and initialization demonstrate themselves
> pretty clearly and are in the domain of the PSW being used.  If there
> are going to be subtle SGX application operability issues that need to
> be found they will be in the new ECALL and exception handling
> mechanisms.

Fair enough, no I have not tested those mechanisms. Apologies, I should 
have removed that line from the quoted text.

-Jordan