I just verified the behavior on all Ubuntu Pro versions for 16.04, 18.04, 20.04, 22.04:
- The behavior works great on all of these provided that the user remembers to check off "Guest services" in the Hyper-V Manager VM's Settings. Additionally, hv-fcopy-daemon.service, hv-kvp-daemon.service, and hv-vss-daemon.service were all smart enough to start/stop dynamically themselves at runtime whenever the respective integration services checkbox in the Hyper-V Manager are enabled/disabled. ^ So the bug described appears fixed in those releases. I also tested Ubuntu Pro 24.04, and there's definitely an issue still that I had touched on in my last comment. In more detail: 1) `/lib/udev/rules.d/60-fcopy-daemon.rules` attempts to tag a virtual device in systemd aligning with the `vmbus/hv_fcopy` driver, and was previously how this systemd virtual device setup a dynamic "Wants" on hv-fcopy-daemon.service whenever the "Guest services" checkbox is enabled/disabled in Hyer-V Manager. 2) Because the "vmbus/hv_fcopy" driver is removed in kernel >= 6.10, the kernel never creates `/dev/vmbus/hv_fcopy` anymore, then it is impossible to satisfy the condition which hv-fcopy-daemon.service depends upon during startup, so it never willingly starts itself when booting. 3) Even when I get everything in my hyper-v VM setup correctly with "Guest Services" enabled, it appears that `/sys/bus/vmbus/devices/eb765408-105f-49b6-b4aa-c123b64d17d4/uio` path is never created; although the parent folder is dynamically created/destroyed anytime "Guest Services" is enabled/disabled (just no "uio" file inside it). 4) Manually launching `hv_fcopy_uio_daemon -n` as root when "Guest Services" is enabled in Hyper-V Settings causes it to exit with an error stating that it expects the above path to exist. @ebonato This might require a separate patch for 24.04 and above, due to all those releases running kernels >= 6.10. hv_fcopy_uio_daemon just doesn't work at all on those kernels. It's probably related to this ticket in the overall symptom, although the overall issue on those newer releases now appears to be more caused by Microsoft's recent "uio" refactoring in kernel 6.10 and above. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1766300 Title: hv-fcopy-daemon service fails to start if /dev/vmbus/hv_fcopy doesn't exist To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1766300/+subscriptions -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
