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Date:   Fri, 8 Nov 2019 10:20:31 +0200
From:   Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
To:     Sean Christopherson <sean.j.christopherson@intel.com>
Cc:     linux-kernel@vger.kernel.org, x86@kernel.org,
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        Suresh Siddha <suresh.b.siddha@intel.com>
Subject: Re: [PATCH v23 12/24] x86/sgx: Linux Enclave Driver
Message-ID: <20191108082031.GC3370@linux.intel.com>
References: <20191028210324.12475-1-jarkko.sakkinen@linux.intel.com>
 <20191028210324.12475-13-jarkko.sakkinen@linux.intel.com>
 <20191029092920.GA14494@linux.intel.com>
 <20191030093045.GB12481@linux.intel.com>
 <20191031211252.GC10507@linux.intel.com>
 <20191105111057.GA20879@linux.intel.com>
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On Tue, Nov 05, 2019 at 01:11:22PM +0200, Jarkko Sakkinen wrote:
> I'll add @count to address this. This output field will contain the
> number of bytes actually written instead of overwriting input
> parameters, which is a bad practice in anyway.
> 
> We don't need to actually cap to anything but API must be able to
> support such scenario. Caller must be prepared to deal with the
> situation where the return value is zero but @count < @length.

I summarized here my reasoning on @count:

https://lore.kernel.org/linux-sgx/20191108081331.GB3370@linux.intel.com/

/Jarkko