Hello, I will retest this with the sru kernel. The udevadm monitor appears to monitor things that it knows about.... thus first one needs to load nbd module, start monitor, unload nbd module, then proceed with the test case.
I've started validating this on wednesday, but had to travel away from a computer for an emergency =/ will test this first thing on monday. -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux in Ubuntu. https://bugs.launchpad.net/bugs/696435 Title: wait-for-root fails to detect nbd root Status in linux package in Ubuntu: Fix Released Status in nbd package in Ubuntu: Invalid Status in systemd package in Ubuntu: Fix Released Status in linux source package in Xenial: Fix Committed Status in systemd source package in Xenial: Confirmed Bug description: [Impact] Kernel does not generate any events when ndb-client connects /dev/nbd0 devices, therefore it is impossible to monitor/react to the state of /dev/nbd0. [Fix] Generate change uevent when size of /dev/nbd0 changes [Testcase] * Start udevadm monitor * modprobe nbd * use ndb-client to connect something to /dev/nbd0 * observe that there are change udev events generated on /dev/nbd0 itself [Regression Potential] There is no change to existing uevents, or their ordering. There is now an addition change event which will cause systemd to mark ndb devices as ready and trigger appropriate actions [Original Bug Report] When using an nbd root, wait-for-root blocks for 30 seconds before booting continues successfully. Using Ubuntu Natty, related packages versions: nbd-client 1:2.9.16-6ubuntu1 initramfs-tools 0.98.1ubuntu9 The wait-for-root call from /usr/share/initramfs-tools/scripts/local: while [ -z "${FSTYPE}" ]; do FSTYPE=$(wait-for-root "${ROOT}" ${ROOTDELAY:-30}) # Run failure hooks, hoping one of them can fix up the system # and we can restart the wait loop. If they all fail, abort # and move on to the panic handler and shell. if [ -z "${FSTYPE}" ] && ! try_failure_hooks; then break fi done I replaced wait-for-root with a sh script that did `set >&2`, here are the relevant environment variables at the time wait-for-root was called: ROOT='/dev/nbd0' ROOTDELAY='' ROOTFLAGS='' ROOTFSTYPE='' nbdroot='192.168.0.1,2011' It's probably worth noting that "nbd0: unknown partition table" was displayed asynchronously 1-2 seconds after wait-for-root was invoked and while it was still waiting. But I tried adding a "sleep 5" as the last line of local-top/nbd, so that the nbd message was displayed a lot before wait-for-root was called, and it didn't make a difference. So I don't think a race condition is involved in this problem. Temporarily I'm passing rootdelay=1 in the kernel command line to work around the problem. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/696435/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp
