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Thread-Topic: [PATCH v2 2/6] xen: backends: touch some XenStore nodes only if device... 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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: 4c74207c-3b30-465f-d588-08dbebad7edd X-MS-Exchange-CrossTenant-originalarrivaltime: 22 Nov 2023 22:50:59.2907 (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: eCLUVjJVrgAM0TD8IhxGNvnI/2SL/DOGVZezbgMNrbN96oTgVZ9lQfhPewhCchYgnHe+Z3ey70If0euvV5UInyOQeli1cmWLIEuyNm72YWI= X-MS-Exchange-Transport-CrossTenantHeadersStamped: AM7PR03MB6354 X-Proofpoint-ORIG-GUID: Qjx8yhmtka4ON3rEmWgfzSzT2wYnNRwZ X-Proofpoint-GUID: Qjx8yhmtka4ON3rEmWgfzSzT2wYnNRwZ 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=2023-11-22_18,2023-11-22_01,2023-05-22_02 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 mlxscore=0 malwarescore=0 adultscore=0 mlxlogscore=948 priorityscore=1501 bulkscore=0 impostorscore=0 spamscore=0 clxscore=1015 phishscore=0 suspectscore=0 lowpriorityscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2311060000 definitions=main-2311220166 Hi Paul, Paul Durrant writes: > On 21/11/2023 22:10, Volodymyr Babchuk wrote: >> was created by QEMU >> Xen PV devices in QEMU can be created in two ways: either by QEMU >> itself, if they were passed via command line, or by Xen toolstack. In >> the latter case, QEMU scans XenStore entries and configures devices >> accordingly. >> In the second case we don't want QEMU to write/delete front-end >> entries for two reasons: it might have no access to those entries if >> it is running in un-privileged domain and it is just incorrect to >> overwrite entries already provided by Xen toolstack, because toolstack >> manages those nodes. For example, it might read backend- or frontend- >> state to be sure that they are both disconnected and it is safe to >> destroy a domain. >> This patch checks presence of xendev->backend to check if Xen PV >> device is acting as a backend (i.e. it was configured by Xen > > Technally *all* XenDevice objects are backends. > Yes, you are right of course. I'll rephrase this paragraph in the next version. --=20 WBR, Volodymyr=