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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?utf-8?B?RHpoTlFuM0IvUnRiMFRTQktMMWJuSGVHcHBIRjB5TUpjUGZOakI4b2RyOHpS?= =?utf-8?B?ZVY1VEtuak83R2w2N0JsV3gxdk5GdjJSTjEzYzYreEdnM1A1bnpNL1ozeFhU?= =?utf-8?B?T0RDUTVjZ0tmMkNJdEZya2VTTHlUUmZGYk0vYVhHT21sRVFZQk9Hak5oRDRU?= =?utf-8?B?L2I2a3BqMTdidjlIZ3N5VmRqOExlVlcyWkJxemxQUi9zQVQwY1FMbXQ5K01x?= =?utf-8?B?dFhOemtZK1JwV3lpN0doTGlmRjEvclZCWHF5d0p4Y2txaVk4azF3T29DRy90?= =?utf-8?B?V0NLR2x3SVVlUVB1cGM2Qjh0a1B2QS9hd29xc1VYT080TGxpT1lWN2RHU0VU?= =?utf-8?B?WlIxZVA5Y2VlejZnM1hYQW9kRVN0VW5sb2pqeXkwbGY3WnNoSUQrWmZ1UnpJ?= =?utf-8?B?RFZZalFTbFhpWEJFaDFlOTFqTFFlenVFQmRMcGdGVGhyUWlyODVOVGVhdXRH?= =?utf-8?B?T21VSDlnc01uYkZac2tBWEhraEw4WnhINCtibmpjOXNMRG9jQTJpS04xUGxB?= =?utf-8?B?VEhSMUlYNGZ2bGpFa1U0M2VNR0hzdWU2LytacjlxK1FYdzZSSnVnOVRzYkpW?= =?utf-8?B?M0hIWjNNbmNhRUgrcHA1S2JyeFZmZEMvOXJMRjNKbTNmeDAzVFRKcmR6SjEy?= =?utf-8?B?TlJLY3FCSVlhb25hM1A0RTU2Znc1aU16WDQrcGVSQVg2SjZJekE5M2JUWVJJ?= =?utf-8?B?K3A2YUFDemdrT3Q5Lys0bWVUcHJmWU53SW5QUEdPSjUzcDUxRkJTbzEwNjQr?= =?utf-8?B?UkFvZEp2ZWJWQmZ6cHlZaE9BMkdFd3lERzR6aWtJRlYvU3NnQ2puRHdPaWVj?= =?utf-8?B?bFkzWWM2ZHVJWVRFM09Sak1Ec1BqUzB0Qms0WGJmWXczYXA2aWRSRnNEcVlI?= =?utf-8?B?NU8xemZKampJRTFWak83a0hhNGNDVDF6bkxSKytEVk93SCtVQ25DTk1CWEVZ?= =?utf-8?B?QlpBTTBRVHZKWXdxNkxpeXA4WFdtS0tjVkdCWDAvUThoWWZ4VFJubFh2ZUV5?= =?utf-8?B?MmhaMTNjNGoxV1RiU09YSmVkd3JFSkJESEhRSGcvOFp5MjNaeTRzeWsvT29V?= =?utf-8?B?U3kvSENWK2UxVndsNlM2SVJGay9qaG03TkhLUmUvaGFZVkNNaCtwMmxpVVZH?= =?utf-8?B?ck1XRU5tV1poRkJ5bnQyeUFsN2cwa3N1bTYwRFBaei95czBEb1BxZysxUFBY?= =?utf-8?B?MU1rMFA0Tkd5UUhDNEt2TVB1TmJ3N3QxNlZucGpaQ0hudk5COVdOQTZuNVh2?= =?utf-8?B?SjVFdzhJaFgxY1ZEOUxxSzhMeVF0R0VqWS8wSHpKTm00aldPS3lPN0hqVVlE?= =?utf-8?B?RjE4QkYvME1LWDVydU5CMmIzTTYxaFp5SHhsTG9QcHc4RkUwcmZpWUEwQUkx?= =?utf-8?B?M2tqQU53SXVBUXRNT2FBUisxTjdsU2ttdEk2V0FzbXVscTlBZlRQV3NVRzh5?= =?utf-8?B?TTcvOFEwa2laUm9JQWdRTGkvZlVnNWh5eVJ6eFU4dmVHdmh0VDdaWVByUFdl?= =?utf-8?B?ZEZFZ2toUzVrWHkxeno1VWFwNWJtRUNwQVFFV1Via3BHM3pKSStMSEptWmtq?= =?utf-8?B?L2FkV2VUNFZKRGRnejBuWUp3b2daNWk3aW9pL24zVmlkNVNyZGNQOXFrc1Zj?= =?utf-8?B?VFBVZ0d6UHNhWDgraXQzOEx6aUtydlpXbkN5Wi8wSzR6c293TjFjTTZJaHIr?= =?utf-8?B?em5RWWZyRXhyL3NtUGZPMlBYUTVIZWhhTzU0V2RBTnV3eG1sYXJLbHdiREtO?= =?utf-8?Q?4JOVo3StYSKILcOPawYbNQIlooY5vRjKd9uWZ3d?= X-OriginatorOrg: suse.com X-MS-Exchange-CrossTenant-Network-Message-Id: b9473b6e-d751-4c77-8da5-08d96c8464d4 X-MS-Exchange-CrossTenant-AuthSource: AM0PR04MB5587.eurprd04.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 31 Aug 2021 13:36:53.3999 (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: ab8aVX/M3cpx9xWfp3DE/dXqSpGE/uivQkL8G80QqxX9RhTHvYE+BF0jX6SyEWow/8swCdrhZh8iZrcs0ETDfg== X-MS-Exchange-Transport-CrossTenantHeadersStamped: AM8PR04MB7441 On 31.08.2021 15:27, Andrew Cooper wrote: > On 31/08/2021 14:19, Jan Beulich wrote: >>>>> @@ -1095,6 +1101,17 @@ static int __init pvh_setup_acpi(struct >>>>> nr_pages = PFN_UP((d->arch.e820[i].addr & ~PAGE_MASK) + >>>>> d->arch.e820[i].size); >>>>> >>>>> + /* Memory below 1MB has been dealt with by pvh_populate_p2m(). */ >>>>> + if ( pfn < PFN_DOWN(MB(1)) ) >>>>> + { >>>>> + if ( pfn + nr_pages <= PFN_DOWN(MB(1)) ) >>>>> + continue; >>>>> + >>>>> + /* This shouldn't happen, but is easy to deal with. */ >>>> I'm not sure this comment is helpful. >>>> >>>> Under PVH, there is nothing special about the 1M boundary, and we can >>>> reasonably have something else here or crossing the boundary. >>> As long as we have this special treatment of the low Mb, the boundary >>> is meaningful imo. I'd see the comment go away when the handling in >>> general gets streamlined. >> I should have added: And as long as Dom0's E820 map gets cloned from >> the host's, which will necessarily consider the 1Mb boundary special. > > Not when you're booting virtualised in the first place. You mean when Xen itself runs in PVH (not HVM) mode, and then in turn has a PVH Dom0? And if the underlying Xen has not in turn cloned the E820 from the host's? That's surely too exotic a case to warrant removing this comment. If you insist, I can mention that case as a possible exception. Jan