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Date:   Mon, 23 Jul 2018 16:08:22 -0600
From:   Jason Gunthorpe <jgg@ziepe.ca>
To:     Tadeusz Struk <tadeusz.struk@intel.com>
Cc:     James Bottomley <James.Bottomley@HansenPartnership.com>,
        Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>,
        linux-integrity@vger.kernel.org,
        linux-security-module@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] tpm: add support for partial reads
Message-ID: <20180723220822.GJ532@ziepe.ca>
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On Mon, Jul 23, 2018 at 03:00:20PM -0700, Tadeusz Struk wrote:
> On 07/23/2018 02:56 PM, Jason Gunthorpe wrote:
> > The proposed patch doesn't clear the data_pending if the entire buffer
> > is not consumed, so of course it is ABI breaking, that really isn't OK.
> 
> The data_pending will be cleared by the timeout handler if the user doesn't
> read the response fully before the timeout expires. The is the same situation
> if the user would not read the response at all.

That causes write() to fail with EBUSY

NAK from me on breaking the ABI like this

Jason