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charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 X-OriginatorOrg: epam.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-AuthSource: VI1PR03MB3710.eurprd03.prod.outlook.com X-MS-Exchange-CrossTenant-Network-Message-Id: b6951589-d730-4fca-41fc-08dbe559261e X-MS-Exchange-CrossTenant-originalarrivaltime: 14 Nov 2023 21:32:05.6802 (UTC) X-MS-Exchange-CrossTenant-fromentityheader: Hosted X-MS-Exchange-CrossTenant-id: b41b72d0-4e9f-4c26-8a69-f949f367c91d X-MS-Exchange-CrossTenant-mailboxtype: HOSTED X-MS-Exchange-CrossTenant-userprincipalname: zVnjFs1Cx29zcI2sOhPvk8r9rtF5Khwo30YOPhc5HMRPWU6MH9MOOB1EhFn5iANG7JCkbEzr2hob5arKRKzsTJxXotcxsAqMeFWcnrA2QL4= X-MS-Exchange-Transport-CrossTenantHeadersStamped: DBBPR03MB7132 X-Proofpoint-GUID: 7TXFmSFJZ8g1Y4MIqHsTDLXTIuUb1Smj X-Proofpoint-ORIG-GUID: 7TXFmSFJZ8g1Y4MIqHsTDLXTIuUb1Smj X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.272,Aquarius:18.0.987,Hydra:6.0.619,FMLib:17.11.176.26 definitions=2023-11-14_22,2023-11-14_01,2023-05-22_02 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 lowpriorityscore=0 mlxlogscore=877 malwarescore=0 priorityscore=1501 impostorscore=0 phishscore=0 clxscore=1015 mlxscore=0 spamscore=0 adultscore=0 suspectscore=0 bulkscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2311060000 definitions=main-2311140157 Hi David, David Woodhouse writes: > On 11 November 2023 16:51:22 GMT-05:00, Andrew Cooper wrote: >>On 11/11/2023 8:18 pm, David Woodhouse wrote: >>> On 11 November 2023 08:43:40 GMT-05:00, Andrew Cooper wrote: >>>> Furthermore, the control domain doesn't always have the domid of 0. >>>> >>>> If qemu wants/needs to make changes like this, the control domain has = to >>>> arrange for qemu's domain to have appropriate permissions on the nodes= . >>> Right. And that's simple enough: if you are running QEMU in a >>> domain which doesn't have permission to create the backend >>> directory and/or the frontend nodes, don't ask it to *create* >>> devices. In that case it is only able to connect as the backend for >>> devices which were created *for* it by the toolstack. >>> >>> The criterion used in this patch series should be "did QEMU create this= device, or discover it". >>> >> >>Yeah, that sounds like the right approach. > > I think we want to kill the xen_backend_set_device() function and > instead set the backend as a property of the XenDevice *before* > realizing it. Not sure that I got this. Right now device is property of XenBackendInstance. Are you proposing to make this other way around? Right now I am looking for a place where to store the information of XenDevice creator. My plan was to add "found_in_xenbus" property to XenDevice and set it in xen_backend_device_create. --=20 WBR, Volodymyr=