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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?Z4rJDDI9w/9MHd1eY+3pDj96oaGJByo+94I8fIu6NNU//cUSAyiVSc3uvLFs?= =?us-ascii?Q?XP2gF3E6EKV4JYvBNqxeOE1UpB/yXKnkZZg+t/bxO5qoEcicu7CztxN6o80F?= =?us-ascii?Q?RZza1ypc4RPhBKkAR+zfoL0tQhKQcgjEGJwSEyHs/R8eDDASknYg3u9mRHjh?= =?us-ascii?Q?Hct3M0XQGvkdUq2JEh0ykAhDyJ62S672xHcUc4IaABHt8fQrPM1s87eVBMLM?= =?us-ascii?Q?VSa3zgHe2mPdps7stOy1+oeiDpLmYV947DY8ckvKAb5zYbiaVvjNF0mJM5xo?= =?us-ascii?Q?WTjUm9DQMXb9JCWaxGivtVd2u6O2s1r2SgUMseGvfa+ic/RInXdb9oqRGdNc?= =?us-ascii?Q?q0E8T4PpxOb2+jw7Jfavb11/4UXatM9xe5gaEoa8fE10OTFrPfyhX4CqEdu4?= =?us-ascii?Q?bcN5fUtGwhvaVotHX+PTMxrAqf/oULMDJXoFda5xsdfxjt3GURjoU+qhw6NK?= =?us-ascii?Q?Za6FFp20oI33VB4obxOj1WwwAFC4I0cyNMUuAta5wDxH0oCH+qAu8CBUi3vj?= =?us-ascii?Q?+Grg0SJBnRMM8weXKIe1RXfY9lIJll6ROEoftQ/RkNTA65VjG9RU5lahegNX?= =?us-ascii?Q?n+fSyWKJ9Z/Odf+VpxkIPxQLJ99n1zghr9jPdnEmtUBlBKfnR3bw2cIi5dLG?= =?us-ascii?Q?j2LLNRZbApoi6jqIfGEsmwAZozQevjI912BAoC54lDF3AtyTyAiZ+gim0VWa?= =?us-ascii?Q?QieXI2xZZN9rGE/8eBMrmifokLNSnEGnAElD0/NxnL78C+d/M+qjhza7z4iN?= =?us-ascii?Q?62+Hvroh4+0Jw1g8KJptcedF+mTiQ18zKvyKAoB/f1yS58R949SDAGmkiEkg?= =?us-ascii?Q?Gj7JiMSxNk3oQK2Y5LUKmJJpniXgLw6xRhVdMee5Ga1292OJ3fSDcrbU3OXh?= =?us-ascii?Q?OO5WhNGNGyFAgw92nFHMcG6OOeCZKeNZf97jJzZz94dBsFJE2TdUwh4M8nJX?= =?us-ascii?Q?nYheABEFDdVsR0QHigXBKPHyyLtdBpuak+U6gdaYtVkdTxxLwxtq9g9Ovby8?= =?us-ascii?Q?Q542Qw7PQ0ss10Uujf2KaFX6ew0iW5lqO6+f3wem3Mbv5cE1Wch9bDlQeUIO?= =?us-ascii?Q?qTME4ws69YA1k9NZf4naSYM48EctPel3Di+sxPiHwQO1WnJl//mGH0igiZZg?= =?us-ascii?Q?k6V2RBqfw5+WzNYAvW0f5Mhj+f6ZY0OaAfjFsBE/tWamGWNfx6p5Dl5GEDba?= =?us-ascii?Q?kdrxtxU7Z3oxoEurRvmit9Y/VXirvVkx52Z3K2GlysT10IL/rKCYkcUBFHs6?= =?us-ascii?Q?bajEusIeAtdqH2oPevkg2a69wyFvsIOyDXCkn73lG1BKik+l4CJOZ3B23HLj?= =?us-ascii?Q?nRV5wHlSdTJ0gpLer5cegNyLOrrBpMmsYqvJY00/ZQLHicJPlkWdb7Acrfhc?= =?us-ascii?Q?Mmdx/40A3IVJE+q9cRLS3uEluPu4VSUnM4bZkolVYcpRl/0QCPyS2di22+H9?= =?us-ascii?Q?FoRnHXXQ2iukux18nxgdP6NRVpeBnAdEeJnBGYz3PL53UcKpZliq4GCqzoDq?= =?us-ascii?Q?8yTfahqU5mWRF5xDLTPB0+70z8KLhxBv1SIJLaY0ix6JYvvUmZo1kMyMTmdD?= =?us-ascii?Q?3+WqkFWUqgNMNC2ZN6q1bXw/SOSwGMA/xK7OtKEZzGYOK8DzsEfprjVy4ZH5?= =?us-ascii?Q?o2XWyYimZe8GSbjCJ6BufYY=3D?= X-OriginatorOrg: suse.com X-MS-Exchange-CrossTenant-Network-Message-Id: ea07186d-6093-427c-394b-08d9b3f3c242 X-MS-Exchange-CrossTenant-AuthSource: VI1PR04MB5600.eurprd04.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 30 Nov 2021 11:22:56.9149 (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: 6kjvSW0r3No/nsmi4A4pnllZhH3xySUu3wjrFsjs1tc710fHVTwLj8h1V+JcdCEo5EdJDHFki1swftH4gEcg4A== X-MS-Exchange-Transport-CrossTenantHeadersStamped: VI1PR04MB6304 On 30.11.2021 12:14, Andrew Cooper wrote: > On 30/11/2021 10:33, Jan Beulich wrote: >> On 30.11.2021 11:04, Andrew Cooper wrote: >>> It has been 4 years since the default load address changed from 1M to 2= M, and >>> _stext ceased residing in l2_xenmap[0]. We should not be inserting an = unused >>> mapping. >>> >>> To ensure we don't create mappings accidentally, loop from 0 and obey >>> _PAGE_PRESENT on all entries. >>> >>> Fixes: 7ed93f3a0dff ("x86: change default load address from 1 MiB to 2 = MiB") >>> Signed-off-by: Andrew Cooper >> Reviewed-by: Jan Beulich >> >> I guess this may be worth backporting despite not having any immediate >> adverse effect. >=20 > I'd say so, yes.=C2=A0 I too can't see an adverse effect right now, but I= 'm > definitely wary of stray executable mappings lying around. >=20 >=20 > In principle, it would be nice to reclaim the 2M of space (which only > exists for the MB1 path IIRC), but then we're getting into a position > where xen_phys_start isn't really that any more. Well, xen_phys_base might be slightly more accurate, but apart from that I do think that we reclaim that space (as much as we did reclaim the 1Mb before the change of the default load address): if ( efi_boot_mem_unused(&eb_start, &eb_end) ) { reserve_e820_ram(&boot_e820, __pa(_stext), __pa(eb_start)); reserve_e820_ram(&boot_e820, __pa(eb_end), __pa(__2M_rwdata_end)); } else reserve_e820_ram(&boot_e820, __pa(_stext), __pa(__2M_rwdata_end)); Jan