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Message-ID: Date: Tue, 15 Nov 2022 09:14:07 +0100 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:102.0) Gecko/20100101 Thunderbird/102.4.2 Subject: Re: [PATCH 2/2] Do not access /dev/mem in MSI-X PCI passthrough on Xen Content-Language: en-US To: =?UTF-8?Q?Marek_Marczykowski-G=c3=b3recki?= Cc: Stefano Stabellini , Anthony Perard , Paul Durrant , "open list:X86 Xen CPUs" , qemu-devel@nongnu.org References: <20221114192011.1539233-1-marmarek@invisiblethingslab.com> <20221114192011.1539233-2-marmarek@invisiblethingslab.com> From: Jan Beulich In-Reply-To: <20221114192011.1539233-2-marmarek@invisiblethingslab.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-ClientProxiedBy: AS9PR04CA0063.eurprd04.prod.outlook.com (2603:10a6:20b:48b::9) To VE1PR04MB6560.eurprd04.prod.outlook.com (2603:10a6:803:122::25) MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: VE1PR04MB6560:EE_|VI1PR04MB7181:EE_ X-MS-Office365-Filtering-Correlation-Id: cabe90a5-e738-4d3c-aa31-08dac6e15f0d X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0; 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This has been changed in Xen, so QEMU can now use its > cached value of the register instead. > > The Pending Bit Array (PBA) handling is for the case where it lives on > the same page as the MSI-X table itself. Xen has been extended to handle > this case too (as well as other registers that may live on those pages), > so QEMU handling is not necessary anymore. Don't you need to check for new enough Xen for both aspects? Jan