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Message-ID: <694bdf12-ab8f-9896-30b3-3b2d7bc3d892@suse.com> Date: Mon, 9 Jan 2023 09:35:42 +0100 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:102.0) Gecko/20100101 Thunderbird/102.6.1 Subject: Re: [PATCH 01/11] x86/shadow: replace sh_reset_l3_up_pointers() Content-Language: en-US To: Andrew Cooper Cc: Wei Liu , Roger Pau Monne , "Tim (Xen.org)" , George Dunlap , "xen-devel@lists.xenproject.org" References: <074dc3bb-6057-4f61-d516-d0fe3551165c@suse.com> <03ae5a1a-4417-0aa0-27d8-833ade20cc0b@suse.com> From: Jan Beulich In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-ClientProxiedBy: FR2P281CA0056.DEUP281.PROD.OUTLOOK.COM (2603:10a6:d10:93::7) To VE1PR04MB6560.eurprd04.prod.outlook.com (2603:10a6:803:122::25) MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: VE1PR04MB6560:EE_|AM7PR04MB7093:EE_ X-MS-Office365-Filtering-Correlation-Id: 18e48e0b-6108-4028-1a5a-08daf21c7dca X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0; 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This utilizes the fact that such list >> fragments are traversed only for multi-page shadows (in shadow_free()). >> Furthermore sh_terminate_list() is a safe guard only anyway, which isn't >> in use in the common case (it actually does anything only for BIGMEM >> configurations). >> >> Signed-off-by: Jan Beulich > > Acked-by: Andrew Cooper Thanks. > I think.  The reasoning seems plausible, but it would probably benefit > from someone else double checking. Okay, I'll wait some to see whether Tim or George may voice a view. Perhaps until the end of this week, committing early next week if no contrary indications appear. The "good" thing here is that all modern 64-bit guests undergo this transition aiui, so the code is / will be properly exercised. Jan