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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?1sBOgn0OjUSHx2xc/S/c3Jfeh7B4s74fsoGq2zWgEEDxowF/VAnrKpxt4S/a?= =?us-ascii?Q?L85DyczzEu7WUMd3z6ZmZFxCXPsKH6Qn+VDlJbwdQiuKp1InlJugzAOD6Elz?= =?us-ascii?Q?lAmmZ8w2yYBk9NNV9IRRkgF0rmHDyC63sbsR8Wop4LsV7XuPn8D2gRxKbFlH?= =?us-ascii?Q?yt5StjVQjtv4zyUwISaU5OfbVtxe589Oa+AHZ3TfzgZNYgioc1ORhZ1KT4C4?= =?us-ascii?Q?iQOZxZMKxD66MDiPm9R55XFWvA7j6X6k44Jl9c92WgHrmwtAlasMnhnAxfSY?= =?us-ascii?Q?WU7nXy5NHJqQgU7Xps3pVKulnhXCOK3OohjRaLLGrEHnVAC5sJguKhPhhWUk?= =?us-ascii?Q?hlEK1RNUd6axU4FJDxx23se/GLuUWkqr/v0Ghixlf+fF4OgJWA/U+qcRiSZa?= =?us-ascii?Q?BCUEM+gKnNTr/UPfJbrHwM4QFVY12o71dx8ZUrPdP9jib34qyHlomSbx4EoV?= =?us-ascii?Q?q6bII+8IZknqdQ4Vnt3fVf99XcowIS5YgAJQsL9hPPO6gP+n9a21NMI/rHx7?= =?us-ascii?Q?yLcynOUL+UJlmIki3mYGwMEdz0BX9ReWE5z19FTgywMjqjy6pZN04D5L2io+?= =?us-ascii?Q?bk3zoMZRf62zE0qbunFvlRmiMbOfzMUfyDpmL1VwEYaPy2ukNF61U60d8NKs?= =?us-ascii?Q?yGym1aDraexRYrr4oFyLEGda2IhTlW4ndHl95uuoJegGqjcrwsOLUw3xgKcH?= =?us-ascii?Q?ARwOpXnySem1SjbYQSpCCkU2QB31SvqDUTHuOenr14fMhe7Pip2qz7SSL7wV?= =?us-ascii?Q?hD8FPJHLorc0Kl/5UR0MjT8D6B++E/ZnSIJQtI7/Cu3VOk8AV6pWR7ueK05z?= =?us-ascii?Q?6BTDBe1jDhIq8yyqKlcpBLLg8+j45SY1nnGMmtRejGz+TaMxDJKN2B4JUi/9?= =?us-ascii?Q?a/IOkvXIJPOlaM2b6TyNv05AfhVdn2xER/XRJgIezvME12WZc16nL4Qg/FEY?= =?us-ascii?Q?JcgU4beROzTtBz0Wa3AuGKDHp1FN9mGZ5+TaU14AqQQZzQV1er6iYJDSul8A?= =?us-ascii?Q?+cPNDYF2/tVBgHzuoRzNIIuGJCrZ6SNU00/zu0gAJEJ4N/0pPwWOlv9BU5BV?= =?us-ascii?Q?6IZoT44tOPN22IhI/19NK6ibFfmWMDbchI/M3f26v0XiYtUdpwRjUeYXoBow?= =?us-ascii?Q?ep+KrdkH/ejyTndQj5Wq+9euq98KEpr1EipggwUzVTM4FjOHSlODokESsFWF?= =?us-ascii?Q?E4RyEZqrDH0BqfLdJhWNvaozzeZ+Vpyq6lUruowc6pK+JkMNktQLUszCUXJi?= =?us-ascii?Q?v2oxiE4VM1h01s24/4xyJHuDtkS809+cLhTn6Qj/AgpeClSbnwJeZNER7DUN?= =?us-ascii?Q?Y9z327WfiTIuaX5exJ9pJy+IesMmDh781VP3qpTxHYuJ35zTiEsW9fDBlxMX?= =?us-ascii?Q?/oIjWcm7jCnju6l0L3EMc37IiC0AwhddAcpTbSZwlr56M3JLyzdbqRKhhvf3?= =?us-ascii?Q?X84LSwxptuU1tPwm+UNB9Xh1BLsh7FLt3JRB10fp4JeHWld1iRc4nKurM+Kt?= =?us-ascii?Q?dbpDt4/6yjZGNrZzkmVRcukhF7KjFZhTbgnpwMQzqCNXah62V1g8+EQuB4YT?= =?us-ascii?Q?m1tXwUlbENGKw3iFLQsrFsoY9HJOKnaC5A0/UqbfnZdJhzeC2b0mF7iKerd4?= =?us-ascii?Q?3kG23pFoEAjftZ8tg4x+ueE=3D?= X-OriginatorOrg: suse.com X-MS-Exchange-CrossTenant-Network-Message-Id: 752f4cb9-f807-4baa-9635-08d9e7146305 X-MS-Exchange-CrossTenant-AuthSource: VI1PR04MB5600.eurprd04.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 03 Feb 2022 12:54:59.7714 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: f7a17af6-1c5c-4a36-aa8b-f5be247aa4ba X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: wMxeGCYmdld29QDBzjH/8XiJ9GrDDz18+saBCYxystrNeIpzKhegRDG7+jL/1tYsX8bfHXfRohV8VrRLg8VF/w== X-MS-Exchange-Transport-CrossTenantHeadersStamped: AM7PR04MB7047 On 03.02.2022 13:45, Oleksandr Andrushchenko wrote: >>> Also memory decoding needs to be initially disabled when used by >>> guests, in order to prevent the BAR being placed on top of a RAM >>> region. The guest physmap will be different from the host one, so it's >>> possible for BARs to end up placed on top of RAM regions initially >>> until the firmware or OS places them at a suitable address. >> Agree, memory decoding must be disabled > Isn't it already achieved by the toolstack resetting the PCI device > while assigning=C2=A0 it to a guest? Iirc the tool stack would reset a device only after getting it back from a DomU. When coming straight from Dom0 or DomIO, no reset would be performed. Furthermore, (again iirc) there are cases where there's no known (standard) way to reset a device. Assigning such to a guest when it previously was owned by another one is risky (and hence needs an admin knowing what they're doing), but may be acceptable in particular when e.g. simply rebooting a guest. IOW - I don't think you can rely on the bit being in a particular state. Jan