Re: [libvirt] [PATCH 11/17] util: Introduce libvirt_udevhelper

On Wed, Oct 26, 2016 at 17:39:35 +0200, Daniel P. Berrange wrote: > On Wed, Oct 26, 2016 at 02:36:58PM +0200, Michal Privoznik wrote: > > This is a small helper intended to be run by udev. On its input > > (either as the only command line argument or in DEVNODE > > environment vairable) it is given a device and on the output it > > will either put nothing (meaning the device is not used by any of > > the libvirt domains), or it will print out security labels in the > > following form: > > > > UID GID SELABEL > > How is this intended to be actually used ? ie what udev rule are > you creating along with this ? Yeah, the rule should really be part of this series. > IMHO we just want the helper to indicate that udev should not do > anything to the device - we should not need udev to ever set labels > itself as libvirt has already set them - we just don't want udev to > remove them. IOW, I don't see the need to print out this info at all. That would be nice, but unfortunately there's no way to tell udev not to touch a specific device (I discussed this stuff with Michal Sekletar). Other udev rules might have already set UID/GID/SELABEL for the device and we can only change it to contain the required content; we can't reset them to "don't change any of these".