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Thread-Topic: [PATCH v2 2/6] xen: backends: touch some XenStore nodes only if device... 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envelope-from=prvs=56903895d3=volodymyr_babchuk@epam.com; helo=mx0a-0039f301.pphosted.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_MSPIKE_H5=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org 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=