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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?DH5JkyAYqct1AKy6iijPsTyFtiTlOnX5l9tW89ctNHTRUwFm9B21fxtiWGXl?= =?us-ascii?Q?xY93t0d7KKbFuB9orni7RioioHd6TePA/LU295Q9WIjCzs4U3NCwSdrqMMRW?= =?us-ascii?Q?HA3W7Yy3cH6+wSBCvLEW62Mvlp7oRwParkYuL496EG/L12dCfJMCW09vSAxA?= =?us-ascii?Q?OrmInCzNR/Y08qiToHuC3zwglnCGjn+Scr7c0Tk/bLS8u9gy4QCdTVrvc9hC?= =?us-ascii?Q?EjzrkLYa10o6HrF6x5ZKXIiHr9yslKbcDXEMzAMTInfvMKHSOvEzmDIh/bZI?= =?us-ascii?Q?3j0FhOeEgaOS4ke+ob51VqZTObQnWLKjp3IKIQNVIxmcGyXEgdSAtpy9qhzc?= =?us-ascii?Q?5u8zSnYxs3w8Z4y2Id1CXWftYEoOMpABqz1D408oMXkUJr3La1ATFJOgqTbx?= =?us-ascii?Q?/WtmaGsaWsHvRGEJASFhW1P+ieDIccqAWCNilLc7OFBdOXGj64iRnvKT8CX+?= =?us-ascii?Q?omuxoWaYu9yY+7YWTyxzQJagcW52W2cpQjD+LnqLEBZYAT/UGPkJkXAjyQQJ?= =?us-ascii?Q?dkv9Jau4pxpMZxIpAI3ndPZCF49FGhU5j+MnAVhfIowaw4qmf7qx+wUwYdPD?= =?us-ascii?Q?tI9e31A88XPMTwrTQC47RMRF56B9uGR4lDmRoxtRCvpPT5gGwelteBiaPa2R?= =?us-ascii?Q?0upobrmzQxaLT3Z45ZVkKTNnCG2vapq/doGmEsCQvn4uJ3/kFqfODeC5JEl/?= =?us-ascii?Q?etXPI06z9mrYVfYC5LtSCUo7BU3v1ZCD3IqVJw4xIiEKkX16QTEpZ2EpXCH/?= =?us-ascii?Q?ExKHey/Ty0QS758sP15fIHzD34aixTcDyhNPsSbKD2N+aCZTd0x+iFaVnpBQ?= =?us-ascii?Q?ry/DFcYMnbNGovBTS6gZFA2yoAtQTlp7UzJSJZQuuHm+3/9YvIGZUGlB6p7N?= =?us-ascii?Q?6qrDzWJwh0oXkzKJTdyeyk0ptUoF2M6heVXq1Nrsg0vg9dXqGOXa8tzrUf7P?= =?us-ascii?Q?nsuAbODLyO3wibZwwdwhruHanvHOBDuQ3DgQBeoL1w0Sn3F223tIRVX1ij5S?= =?us-ascii?Q?lYc5mzj8owBCb4fMads0+I7uKLjno3NTA053Ob8PdaJT4d+GHyEqN0yiwSj8?= =?us-ascii?Q?oXUOqd1VZf19TKjOptL3Wvf3DCEXjApx1F5Xc/ejizIKEvFWDQelBtZXb4iW?= =?us-ascii?Q?dpBg0D83/BShgdm4WvBEafSSU8MhxenZAwZm/MCggPI4M1A8/12dWvf6qgBK?= =?us-ascii?Q?ZQ4sYImbSz/5f5KqMnywy70VfjJVVNzmH7S7ot08nBEMRou7q8HznkV+IjT+?= =?us-ascii?Q?KoFPZWaGYMaqr4my2vTb3T66fK6sWKRIwKyUrs7EUsRjh6aBOd22HyFCwtBK?= =?us-ascii?Q?rI7axSrTyh3/cJwP19qEmo+xaSG1u+Vntf5ZftE1JecW982W54L3HCY7j9f5?= =?us-ascii?Q?kUIxof3lYpbJrftVYStv19RiHD8cMQjHaDKGi2pqBcPalH42YaSPVPWJw6Ba?= =?us-ascii?Q?t6IuILpTtvXVPtWl5dlS77Xa1PVDW3Nz8it2l4b+GODuSKo/AtVUMp2jYusq?= =?us-ascii?Q?VKLB0JRBZnQ0RvXhPZtje84MjYWXJ9hVQDWEv+e5JoOn7bgqXwYcFmxbYAIJ?= =?us-ascii?Q?+TzI6+OjVGrjC+UcjLUlURh0Kmx1Jd3/BOdDVighOSErXlst2GR+bL0smEeL?= =?us-ascii?Q?guF6aChSmJWXH/6HoHTA1aoeLBfqhXpU0AiNDWR1fpbSY3iv26ut4vlJ5ABP?= =?us-ascii?Q?xkUL7E8ohAYZ+I1yCWKI1DULT+s=3D?= X-OriginatorOrg: suse.com X-MS-Exchange-CrossTenant-Network-Message-Id: c353c56b-cdff-4fdf-4098-08d9adbd8bbf X-MS-Exchange-CrossTenant-AuthSource: VI1PR04MB5600.eurprd04.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 22 Nov 2021 13:39:45.7995 (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: 8tAzYQDhrpwp54l/EAzNlAOqkuSjMjkzyFSoJ16+E1aBWjd9xMFH3xsm2rt3c+A1rGJQ3pP4i7f9XLKZd8plJw== X-MS-Exchange-Transport-CrossTenantHeadersStamped: VE1PR04MB6383 On 22.11.2021 13:46, Juergen Gross wrote: > On 22.11.21 11:41, Jan Beulich wrote: >> On 14.09.2021 14:35, Juergen Gross wrote: >>> Add a bitmap with one bit per possible domid indicating the respective >>> domain has changed its state (created, deleted, dying, crashed, >>> shutdown). >>> >>> Registering the VIRQ_DOM_EXC event will result in setting the bits for >>> all existing domains and resetting all other bits. >> >> Generally I view VIRQ_DOM_EXC as overly restrictive already - what if bo= th >> a xenstore domain and a control domain want respective notification? Hen= ce >=20 > The general idea was that in this case the control domain should > register a related Xenstore watch. >=20 >> similarly I'm not convinced a single, global instance will do here. Whic= h >> in turn raises the question whether the approach chosen may not take us >> far enough, and we wouldn't instead want a more precise notification mod= el >> (i.e. not just "something has changed"). >=20 > Yes, that would be the job of Xenstore. It would provide the more > fine grained watches for that purpose. And the watch consumer still wouldn't have a way to distinguish two domain instances using the same ID, would it? >>> @@ -1141,6 +1161,8 @@ static void complete_domain_destroy(struct rcu_he= ad *head) >>> =C2=A0 =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 xfree(d->vcpu); >>> =C2=A0 +=C2=A0=C2=A0=C2=A0 set_bit(d->domain_id, dom_state_changed); >>> + >>> =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 _domain_destroy(d); >>> =C2=A0 =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 send_global_virq(VIRQ_DOM_EXC); >> >> Wouldn't this better be in domain_destroy() immediately after the domain >> has been taken off the list, and hence is no longer "discoverable"? >=20 > In this case the call of send_global_virq() should be moved, too, > I guess? Possibly, albeit I'd see this as a separate change to make. It doesn't seem outright wrong for the vIRQ to be sent late. But I agree with the idea of keeping sending and bit-setting together (ideally, even if this was to stay here, the two would better sit truly side by side). Jan