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Violators will be prosecuted; Thu, 22 Feb 2018 03:47:14 -0000 Received: from d06av22.portsmouth.uk.ibm.com (d06av22.portsmouth.uk.ibm.com [9.149.105.58]) by b06cxnps4074.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id w1M3lECL41877706; Thu, 22 Feb 2018 03:47:14 GMT Received: from d06av22.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 9D3F04C044; Thu, 22 Feb 2018 03:40:50 +0000 (GMT) Received: from d06av22.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 4BB1D4C040; Thu, 22 Feb 2018 03:40:50 +0000 (GMT) Received: from ozlabs.au.ibm.com (unknown [9.192.253.14]) by d06av22.portsmouth.uk.ibm.com (Postfix) with ESMTP; Thu, 22 Feb 2018 03:40:50 +0000 (GMT) Received: from [10.61.2.125] (haven.au.ibm.com [9.192.254.114]) (using TLSv1.2 with cipher DHE-RSA-AES128-SHA (128/128 bits)) (No client certificate requested) by ozlabs.au.ibm.com (Postfix) with ESMTPSA id 33DC4A0146; Thu, 22 Feb 2018 14:47:12 +1100 (AEDT) Subject: Re: [PATCH] ocxl: Add get_metadata IOCTL to share OCXL information to userspace To: Balbir Singh , "Alastair D'Silva" Cc: linuxppc-dev , "linux-kernel@vger.kernel.org" , Arnd Bergmann , frederic.barrat@fr.ibm.com, Greg KH References: <20180221045736.7614-1-alastair@au1.ibm.com> <1519255934.2867.3.camel@au1.ibm.com> From: Andrew Donnellan Date: Thu, 22 Feb 2018 14:47:11 +1100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.6.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-AU Content-Transfer-Encoding: 7bit X-TM-AS-GCONF: 00 x-cbid: 18022203-0016-0000-0000-00000528506D X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 18022203-0017-0000-0000-000028646733 Message-Id: <76092e30-6959-942c-3600-95fb933eada8@au1.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:,, definitions=2018-02-22_01:,, signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 priorityscore=1501 malwarescore=0 suspectscore=0 phishscore=0 bulkscore=0 spamscore=0 clxscore=1011 lowpriorityscore=0 impostorscore=0 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1709140000 definitions=main-1802220048 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 22/02/18 14:41, Balbir Singh wrote: >> Setting it to 0 is for the reader, not the compiler. I'm not clear on >> the benefit of starting the version at 1, could you clarify? > > How do I distinguish between version number never set and 0? The ioctl won't exist without a version number set. -- Andrew Donnellan OzLabs, ADL Canberra andrew.donnellan@au1.ibm.com IBM Australia Limited