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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?Windows-1252?Q?QirCUJ1fU/GF3JnVxbZLBACr1/b8d+TmGc5gj2Dv0m6W0QxkpOgJCI6G?= =?Windows-1252?Q?rqaj46R19yNvQ6Kx+BiS8OMa4NjI+KXzBEpYIcPBFmFgPpYh2R9pQS9M?= =?Windows-1252?Q?fwejlBfgLdtf/dlp+iifUsiTqXAo/ZaN986eW2uk/VVqgLK7Nf6eSO/f?= =?Windows-1252?Q?JmhYCRRpleuvTZIfqjvBUXHU//hgzPAt2XAzJl1wWJC3mkTXLf0rgqmr?= =?Windows-1252?Q?6Fs1CAtOsTzNBINALX4UGVlwqEcfiQOpSAHZuKSb2ILxK5jjcmBnZuns?= =?Windows-1252?Q?CfmZd2S4oMX/Dth2UNm5/rHJoyubyz4tXSLBpaRYjLMotrxAF6UZlOYr?= =?Windows-1252?Q?PPepFEBKW7OUW6CUY255UDAPiFHFUtnIL3dZWd8T1E32UpSW/mmnEQ8d?= =?Windows-1252?Q?A/UK7nDADuZGXEgMjNtLpa3txMgWrOK9r98zmswWlDfiy284HHGwy5cu?= =?Windows-1252?Q?Im+f3iyZZ4uSnbDxSZ4hhH64EnEvVKuQ+sS6c+3l0nXsbGjcgnORdVuz?= =?Windows-1252?Q?Gud7icAIKQfCR608H3uxlUc5Sr4NbZsgPbRQ0scLUZ3KRJ+t35t67roD?= =?Windows-1252?Q?ZQ+Oif4iklzr8/pXarYJGeXncZvB891Tm2OrFzYsibjz2vtJTgW/l65u?= =?Windows-1252?Q?+N+wbCynrJAqqFzhr/iWg0AsXAlT263/XymiirHC7GXbcyFIAHjMhLrQ?= =?Windows-1252?Q?R60R+zjIYDQyz/zAymcG2zrCHibZBlT+wo1ebwdJvQtM09xx4Mq9jOt+?= =?Windows-1252?Q?Vmo8BzQOROz9h8G1EaTlGasaxzljGOqcUIUeQaElAzbhKPnb3Vhl+xS5?= =?Windows-1252?Q?k9atMdmLCIJ/mEdaPsDFyq2N6lZVlGMuPS7Q4ZlC3xYKjdQr6lbvtrdn?= =?Windows-1252?Q?ySGm5u5GhIwQNAD/Z2Uqt6gJ9CcuQGBJwypaWuqZJ1HoxweyoJWI7YDa?= =?Windows-1252?Q?pRpFG3Ys7CApNJeDokHmbeYxFGq0Pl/yTo9xZIn4EXoAi2abCZDAzS91?= =?Windows-1252?Q?TC8qnS4Pw7mWz8g4R8L8LkKmaCYO7Bqz5K+YCNjiOHAtiIIH4c3SI09I?= =?Windows-1252?Q?IgZBEmNlDk2QQU2MEcZwmF0fEeu3hIpBiX0nuWawJ75SYBlwHLRcZRyx?= =?Windows-1252?Q?aN8SGHL129A0FVgbwotdTi+QcyJDmj81G99U+n3U+hZUQQthR/R+zN8R?= =?Windows-1252?Q?G4XioFjHfgoVul15trlcX+l3ew2mRrGJ8C8+ZZXyr/Zxwj1EzB0bzSRz?= =?Windows-1252?Q?bU3Mo9QymM6i8+lDU59dJ9gFAD47x1/8/YsIUCbIbOrHWtNuO4p5A9Wx?= =?Windows-1252?Q?oU7BCWZzilgz+kDi3aUzxVFMpD1IxW5KmzwkcKAi6PZJEjwz16Na8YZw?= =?Windows-1252?Q?rQDqMBsXLPu6benV36O3uFhH2fGGvNEVmhY0YYzNJw+gNUseh9GvFIp6?= X-OriginatorOrg: suse.com X-MS-Exchange-CrossTenant-Network-Message-Id: 804f2bdb-9019-4642-e7b6-08d93f8e1ab6 X-MS-Exchange-CrossTenant-AuthSource: VI1PR04MB5600.eurprd04.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 05 Jul 2021 08:23:01.6795 (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: DKTN5XDcF/2Bs4OmP9cBjBFODbijo9ghvDFecwj9IDMbi4QlZ8Elh4XW/1R6KVU1eXzYLBPzp9kbY+GMpLPJ9Q== X-MS-Exchange-Transport-CrossTenantHeadersStamped: VI1PR04MB4381 On 05.07.2021 10:02, Olaf Hering wrote: > Am Mon, 5 Jul 2021 09:57:21 +0200 > schrieb Jan Beulich : > >> What is "the grant problem" referring to here? Neither anything above >> nor the offending original commit has any reference to grants, or a >> problem with them. > > When the guest is paused during final transit, the backends will > continue to write into domU memory. As a result the final additional > iteration to verify memory on both sides will always see errors. I see. A similar problem then exists with at least the FIFO event channel per-vCPU control blocks? > The code has no way to know for which pfn such mismatches in page > content can safely be ignored. Well, in principle this can be known, but it's expensive: For a paused domain the grant table can't change anymore. Any pages referenced by a valid non-r/o grant table entry could in principle change. Jan