flock will not block inotify or udev events being emitted. See https://github.com/systemd/systemd/blob/master/src/udev/udevd.c#L322 https://github.com/systemd/systemd/blob/master/src/udev/udevd.c#L409
it will prevent udevd from running the rules against it. Thus effectively the event will be fired and done, but nothing actually executed for it. " /* apply rules, create node, symlinks */" Also, most importantly udevd also takes locks on devices, thus if one cannot take a lock on it, it means it shouldn't be touched yet as udevd is still processing it. Yeah, i read code and ioctls both call, and I have no idea which one is better, or what the difference is. If partx works, cool. But also, I thought udev should be updating partition tables all by itself. I somehow wonder if we even need partx call, if we properly flock the device and trigger udev after everything is done. Udev rules should be safe to be retriggered like that. But also, we should retrigger the expected events which have been skipped. So does growpart create partition? move it? delete/recreate one? i.e does ADD happen? or like REMOVE & ADD? or maybe it's like just MOVE or CHANGE? Do we have logs of the emitted events already? Don't like flags, as then we'll have to supported forever =) maybe env variable? or like simply change in focal and compare focal vs eoan? -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux-azure in Ubuntu. https://bugs.launchpad.net/bugs/1834875 Title: cloud-init growpart race with udev Status in cloud-init: Incomplete Status in cloud-utils: New Status in linux-azure package in Ubuntu: New Status in systemd package in Ubuntu: Incomplete Bug description: On Azure, it happens regularly (20-30%), that cloud-init's growpart module fails to extend the partition to full size. Such as in this example: ======================================== 2019-06-28 12:24:18,666 - util.py[DEBUG]: Running command ['growpart', '--dry-run', '/dev/sda', '1'] with allowed return codes [0] (shell=False, capture=True) 2019-06-28 12:24:19,157 - util.py[DEBUG]: Running command ['growpart', '/dev/sda', '1'] with allowed return codes [0] (shell=False, capture=True) 2019-06-28 12:24:19,726 - util.py[DEBUG]: resize_devices took 1.075 seconds 2019-06-28 12:24:19,726 - handlers.py[DEBUG]: finish: init-network/config-growpart: FAIL: running config-growpart with frequency always 2019-06-28 12:24:19,727 - util.py[WARNING]: Running module growpart (<module 'cloudinit.config.cc_growpart' from '/usr/lib/python3/dist-packages/cloudinit/config/cc_growpart.py'>) failed 2019-06-28 12:24:19,727 - util.py[DEBUG]: Running module growpart (<module 'cloudinit.config.cc_growpart' from '/usr/lib/python3/dist-packages/cloudinit/config/cc_growpart.py'>) failed Traceback (most recent call last): File "/usr/lib/python3/dist-packages/cloudinit/stages.py", line 812, in _run_modules freq=freq) File "/usr/lib/python3/dist-packages/cloudinit/cloud.py", line 54, in run return self._runners.run(name, functor, args, freq, clear_on_fail) File "/usr/lib/python3/dist-packages/cloudinit/helpers.py", line 187, in run results = functor(*args) File "/usr/lib/python3/dist-packages/cloudinit/config/cc_growpart.py", line 351, in handle func=resize_devices, args=(resizer, devices)) File "/usr/lib/python3/dist-packages/cloudinit/util.py", line 2521, in log_time ret = func(*args, **kwargs) File "/usr/lib/python3/dist-packages/cloudinit/config/cc_growpart.py", line 298, in resize_devices (old, new) = resizer.resize(disk, ptnum, blockdev) File "/usr/lib/python3/dist-packages/cloudinit/config/cc_growpart.py", line 159, in resize return (before, get_size(partdev)) File "/usr/lib/python3/dist-packages/cloudinit/config/cc_growpart.py", line 198, in get_size fd = os.open(filename, os.O_RDONLY) FileNotFoundError: [Errno 2] No such file or directory: '/dev/disk/by-partuuid/a5f2b49f-abd6-427f-bbc4-ba5559235cf3' ======================================== @rcj suggested this is a race with udev. This seems to only happen on Cosmic and later. To manage notifications about this bug go to: https://bugs.launchpad.net/cloud-init/+bug/1834875/+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
