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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?zlW4X4REhhKiNE/MevjsvoC6/TK08qr9Ltr8frMiH0tqQxQ1QWqdH+HwN8u7?= =?us-ascii?Q?Eb3u+Y1zkus183hNdzNpIIcvQm2VPFLUSrs0DvPPeOVX+3fDBf6hZejaAJOe?= =?us-ascii?Q?0GgO+Wrspky3VhyesJKtorSQG6pt7Up310suTLZEDALumXXqEw+DDm1mjlYo?= =?us-ascii?Q?XjDOISbJXMBHyPFymVK99FUNF2HVznN3zBuPPLyYFrV+BxLObB0Rzd4wAqkM?= =?us-ascii?Q?eLIS7hzLxCfU+aq7BYXvrPrnlYKW1ubLasYNHnsy3HOwn/FePk8kOhRuFDTr?= =?us-ascii?Q?6mw3n8piZwG423o+/q2oV3+t5kODicQ/4Xm3hapkJVIfXmKAcu7wHy0ZDeey?= =?us-ascii?Q?IBIQc1/gcJ2DcPpJgs08esynTlTLNziSXiaClgm3vLCdBJtG7G48uzwhhNFp?= =?us-ascii?Q?4O4fbV/VYlrNa55WU/yKhT73iB29NatRSOw1gpIRgowizhTWkYy9Y9qND0Bw?= =?us-ascii?Q?e3IB1CCVUbzZKYGEOKYWIhu/IanugZ/ezHSzn9QshfWw0egUGbW1WGEb+haB?= =?us-ascii?Q?dFU34OV6G9DMZ0RVkVXd95T3kB/u8gJ9C0d6BoJm9laC2xPcOFjj2lp1yWL6?= =?us-ascii?Q?rl8tTXTImQNmPa4psNdGG5NQ86bRlC1HXDvg0Wp7q/KIT8m0qz6hkBJWV9yp?= =?us-ascii?Q?B0IK88D2X+5JOW7I1C2f0kvFndaqxOOQtd+xD2jVYtiEbyXTY5SVynST/qer?= =?us-ascii?Q?ZGKKJHnW8lyhOf8mebFsMSQ63/zMTKLs7kfNBzhf0QXmzHVsyRLGXeR0MT4U?= =?us-ascii?Q?+6bOTnjZImnAYPJ2VHoloVh7mrXbI0u4nwkNjAygzTjCPJO2C5VpQi+mEmR8?= =?us-ascii?Q?ApWFcCB/wVYFow3rn8eLy7Tt/AHO2Esw+AH5bXNNKqTP6S3J7Ij9ZuUaG8Qx?= =?us-ascii?Q?gLmj/VkUZzgW1ern9efay3TuU++lN4u+adGKLszVUgLNU/raMusTNcz76sn3?= =?us-ascii?Q?i+qyoVvdY73hjiFmb3S6QMHkbQyyFXPqxenlUuiwHN3tG8LWS2Ggdpo+kpVj?= =?us-ascii?Q?DE6+iC31iGKXGwApj185i8BG6DYIOMlBMVIwraZwtCoqVouydl49w4tSN7uZ?= =?us-ascii?Q?Ovv+XGrdzjmoTrIVFk88v4Kl3nnVR5249RQPx9dw8ImeHHZk7akLxcniRdP0?= =?us-ascii?Q?w+aJoV55rdcdBk7Gftfikas5uRExmDWCTuiDTdVlhzMVquEObWbzKTZUskRX?= =?us-ascii?Q?kfVUsYte1gEvvE8gEdC0GReuXfdVnH36gT86GoP+LO5fI5Wq06vCujabTlJo?= =?us-ascii?Q?r6qrj9/7owBEPhI1+w9aaiamiY3j0+LkaIRRujIs9STrMsMV6yTrEOZY2/Kz?= =?us-ascii?Q?l3hIyT426xrl7tiLLCgxUTgy?= X-OriginatorOrg: suse.com X-MS-Exchange-CrossTenant-Network-Message-Id: ae305402-d6a9-4425-29f6-08d97f2fd28f X-MS-Exchange-CrossTenant-AuthSource: VI1PR04MB5600.eurprd04.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 24 Sep 2021 07:49:22.3563 (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: zxxrXON+o8YMtMMd40xonpLCpGrsVJb+XQ7uCI+UDeRK3seVLXk1KFkmEdctoug7LfyV3tR/mdAeq5eRULeMSQ== X-MS-Exchange-Transport-CrossTenantHeadersStamped: VI1PR04MB5167 On 24.09.2021 09:30, Julien Grall wrote: > On Fri, 24 Sep 2021, 11:21 Jan Beulich, wrote: >> On 24.09.2021 04:30, Julien Grall wrote: >>> On Thu, 23 Sep 2021, 16:20 Roger Pau Monn=C3=A9, >> wrote: >>>> On Thu, Sep 23, 2021 at 01:47:37PM +0500, Julien Grall wrote: >>>>> On 22/09/2021 14:39, Roger Pau Monn=C3=A9 wrote: >>>>>> On Wed, Sep 22, 2021 at 01:57:02PM +0500, Julien Grall wrote: >>>>>>> On 22/09/2021 13:21, Roger Pau Monne wrote: >>>>>> But it's also arguable that a guest not having a grant table should >>>>>> also likely prevent foreign mapping attempts. Plus such foreign >>>>>> mapping won't work from stubdomains. >>>>> >>>>> There is another option: extend the acquire hypercall to allow >> xenstored >>>>> domain to map the xenstore interface. This would require more work, b= ut >>>> at >>>>> least it would avoid the interesting dependency on the grant table. >>>> >>>> Xen isn't aware of the shared xenstore ring page currently, so that >>>> would mean introducing more knowledge to the hypervisor that what's >>>> strictly required IMO, as Xen has no business in knowing such details. >>>> >>> >>> Well Xen already knows the page for HVM/PVH because the guest retrieve = it >>> through an HMV param. >> >> To be honest using this in such a way would feel like an abuse / layerin= g >> violation to me. >> >=20 > I can see how it can be seen like this. Do you have a better suggestion t= o > be able to map mapping without the foreign mapping interface and the gran= t > table? Well, as was mentioned, PV would need covering anyway. And I think just like with grants the guest should consent with such foreign mappings outside of the "can map everything anyway" category. Hence I think if such a capability is indeed needed/wanted, it ought to be the guest to announce this page to Xen. Jan