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dkim=none (message not signed) header.d=none;kernel.org; dmarc=none action=none header.from=oracle.com; Subject: Re: Support of old Xen versions in the Linux kernel To: Juergen Gross , "xen-devel@lists.xenproject.org" Cc: Stefano Stabellini References: <1e4dc7c0-4364-1095-bb6b-c6341bc58e60@suse.com> From: Boris Ostrovsky Message-ID: Date: Tue, 13 Apr 2021 13:33:25 -0400 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:78.0) Gecko/20100101 Thunderbird/78.9.1 In-Reply-To: <1e4dc7c0-4364-1095-bb6b-c6341bc58e60@suse.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Content-Language: en-US X-Originating-IP: [138.3.201.51] X-ClientProxiedBy: SJ0PR05CA0102.namprd05.prod.outlook.com (2603:10b6:a03:334::17) To BYAPR10MB3288.namprd10.prod.outlook.com (2603:10b6:a03:156::21) MIME-Version: 1.0 X-MS-Exchange-MessageSentRepresentingType: 1 X-MS-PublicTrafficType: Email X-MS-Office365-Filtering-Correlation-Id: bad409d7-f466-4e66-74fd-08d8fea240a0 X-MS-TrafficTypeDiagnostic: BYAPR10MB3574: X-Microsoft-Antispam-PRVS: X-MS-Oob-TLC-OOBClassifiers: OLM:6430; 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As far as I know there is no Xen based > product in productive use with Xen older than 4.2. > > Would we be fine to drop support for older versions (feel free to > suggest other versions than 4.2 as the first to be supported Xen > version)? > > In case the answer is yes, I'd post some patches to clean up the kernel, > including a safety net to bail out in case a feature needed isn't > available. > Sounds good to me. -boris