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Sat, 28 Aug 2021 06:04:26 +0000 Subject: Re: announcing LLpatch: arch-independent live-patch creation To: Peter Swain Cc: live-patching@vger.kernel.org, madvenka@linux.microsoft.com References: <01b7d9fa-d3be-ec36-0863-fd175b62c2b9@virtuozzo.com> From: Evgenii Shatokhin Message-ID: Date: Sat, 28 Aug 2021 09:04:24 +0300 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.11.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit X-ClientProxiedBy: AM0PR08CA0024.eurprd08.prod.outlook.com (2603:10a6:208:d2::37) To DB8PR08MB5019.eurprd08.prod.outlook.com (2603:10a6:10:e0::21) MIME-Version: 1.0 X-MS-Exchange-MessageSentRepresentingType: 1 Received: from [192.168.1.41] (37.144.247.53) by AM0PR08CA0024.eurprd08.prod.outlook.com (2603:10a6:208:d2::37) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.4457.17 via Frontend Transport; Sat, 28 Aug 2021 06:04:25 +0000 X-MS-PublicTrafficType: Email X-MS-Office365-Filtering-Correlation-Id: 2eb3b4bc-d891-496f-3b30-08d969e9b090 X-MS-TrafficTypeDiagnostic: DB6PR08MB2758: X-Microsoft-Antispam-PRVS: X-MS-Oob-TLC-OOBClassifiers: OLM:9508; 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I see. Yes, it is safer to use the same toolchain both for the kernel and for the patch. > As a precondition for LLpatch-patchable kernels, I would recommend moving > to clang-built base kernels This is not always an option ;-) For example, the kernels in our (Virtuozzo) Linux distros are based on those from RHEL. We try to change only what we really need to, otherwise we lose the benefits of a well-tested code base. So, the compiler and even its version are basically fixed for us. Thanks, anyway. > . > Regards, Evgenii