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X-MS-Exchange-AntiSpam-MessageData: =?utf-8?B?d1RlRlBsa2RLd0x2bEJFbmp1T3dVbmpQM0ZxcnI2eVFrZXhUOHBpRUNCU2N4?= =?utf-8?B?cjk5bTM3MUdlRnA4bU04ellkaWI4cmhhWVhtRDhsc0RwRE5xSUZCZnJ4RE5s?= =?utf-8?B?bUhCR3E2M0hCeXBwZ1RvTnFsSlczakE4MkN6WHQ4Qk1RbDFYbVZJWDJ1eUlw?= =?utf-8?B?RDZMVXJ4dHlFRmlHY01JTExaVDcwTUdyaFlSd2hYSUQ3dGdUNzU4UzJhRTN6?= =?utf-8?B?Vm51NEZJazZMbmFQTHlJMjBEMDBNNjkrZmVDekJDRDVvL3NZQUN2MXMrVzRp?= =?utf-8?B?MC9rcEVsbmNsMU54OHkwLzNFeUxVeHlMZUpNMHRLNVJrejk3RHpZanBxclpK?= =?utf-8?B?elcrdkpHTGlEakg3U205Q2I4SGh3K1p1dVJTeUlBV0VxK2NqMHVYWXR0TDBE?= =?utf-8?B?TVdkWGFnbWNBbGVlYnZiWmJpZGFsaWZNNGplVGNkU0Nhd1BZaGFRUDRZV3Qw?= =?utf-8?B?WCs0aWJuMXRsM3JFRCtxdTlDMnAvL01ZMlZXa1B1aXkwN2FaenROb0tpRHJO?= =?utf-8?B?YVF6OVdMTUJIdzdaUFRObGQreGxPbGUxYld4TC9raXVuYUl6aXZiQkIvaU0z?= =?utf-8?B?WmRyZlUrV1dNcTR6Vk9RNlNlU05FMzNRZW5FZHBlUDM2djNrN2pRSTlRRG1a?= =?utf-8?B?di9XNEJlZzVKZ2hzb3hUcWttTGFkREtUN1JrTWUrZmZYYzZaRWk4STVQc2lD?= =?utf-8?B?QXcvK0pYZk4xM1ZmMWJxQlMxN2VId1ZPakxFRmtudU5yVUNLc0JJWjBETFlx?= =?utf-8?B?c3RoTzd2eFJkYnRvNm9scW5CSUxkWWZlc2I3cjY2cUp2S1hiK3c0R1RQREE4?= =?utf-8?B?TEJDRGFrZm5TK0JtbDBKclYzYUpZRVZ1TDQyRXNXMWZ3ajZobms4M3FpVkRq?= =?utf-8?B?L1VuY3NyVWpvWUJOM3RGcWxHVHlWZkl1ZnVNT1VJdlFnV3FsS2lEamgxY2Rl?= =?utf-8?B?OFV2NEw3ZzlZYmtJd3JTNXdPdXk4Y3EzT1lSWm1uM1NsVHhUa0VLTTY4Vzly?= =?utf-8?B?a1dZZ2RHbTNZRklRblN5M01STkM5ZUV2cnQzdzhSZHFUWDZzUzdhWHdveE1S?= =?utf-8?B?VGU2L2xPWGw1a2ljMWl0elhCVFRncStNNHBTY2xRNXpvSDJDaHh5ODJsaFc4?= =?utf-8?B?K2ZDbjBuMUdVNzFzcW9TaFB6U2tWL0J3OEhCNGlXRGszL3pFSUJrdlpsczhK?= =?utf-8?B?Rkh0NnNXT0xjYzRRVE5yV2ZjT0NBZm5hYmNNeDFVR1dTamRFZTR5NkM3ZTNV?= =?utf-8?B?dUwrRXZPRW1kRGJ4MnJrMlJBeTFNV3NuTlpEYWxTUk5YWmZMbmRKT3lkTEpZ?= =?utf-8?B?L2lHbE5VbE4vUW9YbEQvczcyVC9LV0t0YkR0aUU2VTFvTk85UFhWbVhFaVVn?= =?utf-8?B?ZE1HVVlLd3pSbG5NN3h4Vm9RVkdLQS9paXRQOTlXTDBIN0pTanlvUm80bE5n?= =?utf-8?B?dDQvQWZKQWNGdWF0Y25FN3ZCSmVuaFBmL3Q5S0tEQ0V1dWwvOHFTcFNqNGlX?= =?utf-8?B?eGdEMU1UKzBpb3Zsc2VsQW5iaVlJa0NoYXd3cmcyS1ZMdGVqeXRzVHYyd0lG?= =?utf-8?B?bXgzU2g3SThwZ1RJRFdEQXBNbUVBTlhIcmx5YWw3aU40WlFhOUgrWWV3S2Ez?= =?utf-8?B?cWZNeXhDcVRJK2pkKzk2TWJSejkyTGxOVE5aeGVqUmIxeWFWY3JpdVJhVXVX?= =?utf-8?B?MDhJSStENFkydHdLRGVlR1FKM0pKOGFqeUpsMGFmY29pbDdka2ljQ01jeUdj?= =?utf-8?Q?ZIj+Z54LB5CBAbobb312OCWxm1M/6cr0g06o56Y?= X-MS-Exchange-CrossTenant-Network-Message-Id: fff865ed-d647-4e11-08c4-08d8d73c0a1c X-MS-Exchange-CrossTenant-AuthSource: DS7PR03MB5608.namprd03.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 22 Feb 2021 14:13:34.3541 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 335836de-42ef-43a2-b145-348c2ee9ca5b X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: xupR/ArkH1PgQZPjFxRdCNFOn0ybhBNuRFHakNxa/9oYPXxOyOuBKmA7kAFLZXl120t0pPCivlnR1pGIqQqw3w== X-MS-Exchange-Transport-CrossTenantHeadersStamped: DM6PR03MB3674 X-OriginatorOrg: citrix.com On Mon, Feb 22, 2021 at 12:35:21PM +0100, Roger Pau Monné wrote: > On Mon, Feb 22, 2021 at 11:27:07AM +0100, Jan Beulich wrote: > > Now that we guard the entire Xen VA space against speculative abuse > > through hypervisor accesses to guest memory, the argument translation > > area's VA also needs to live outside this range, at least for 32-bit PV > > guests. To avoid extra is_hvm_*() conditionals, use the alternative VA > > uniformly. > > Since you are double mapping the per-domain virtual area, won't it > make more sense to map it just once outside of the Xen virtual space > area? (so it's always using PML4_ADDR(511)) Right, that's not possible for PV 64bit domains because it's guest owned linear address space in that case. It seems like paravirt_ctxt_switch_to will modify the root_pgt to set the PERDOMAIN_VIRT_START entry, does the same need to be done for PERDOMAIN2_VIRT_START? I would also consider giving the slot a more meaningful name, as PERDOMAIN2_VIRT_START makes it seem like a new per-domain scratch space, when it's just a different mapping of the existing physical memory. Maybe PERDOMAIN_MIRROR_VIRT_START? Or PERDOMAIN_XLAT_VIRT_START? Thanks, Roger.