Why akmod fails on F22 for nvidia (and possible other uses)

[Barry Scott]

On Thursday 20 August 2015 16:27:15 Reindl Harald wrote:
> Am 20.08.2015 um 16:20 schrieb Dave Pawson:
> > Updated software via GUI.
> > new kernel 4.1.5-200.fc22.x86_64
> > 
> > Usual song and dance.
> > #akmod --force worked as previously.
> 
> and you are sure the timers are not running?
> 
> "disable" is bulls** if you really want something not have started
> 
> * enable:  start units unconditional
> * disable: start units on triggers/demand
> * mask:    never start soemthing
> 
> systemctl mask dnf-makecache.service
> systemctl mask dnf-makecache.timer
> 
> http://stackoverflow.com/questions/30720786/cannot-disable-systemd-service

I have not hit any problem with using disable in practice. But Its nice to 
know about mask, thanks for the info.

Barry


> 
> > On 24 July 2015 at 15:17, Barry Scott <barry at barrys-emacs.org> wrote:
> >> I did some investigation as to why akmod will fail to install a
> >> the nvidia dirver when a new kernel turns up.
> >> 
> >> The problem is that dnf-makecache.service runs at the same time
> >> as akmods.service. DNF locks the RPM data base which prevents
> >> akmods from installing the RPM's it built.
> >> 
> >> Here is a extract from 346.72-2.1-for-4.0.8-300.fc22.x86_64.failed.log
> >> 
> >> Running transaction
> >> RPMDB already locked by 2285
> >> 
> >>    The application with PID 2285 is: dnf
> >>    
> >>      Memory : 116 M RSS (677 MB VSZ)
> >>      Started: Sat Jul 18 12:09:56 2015 - 06:20 ago
> >>      State  : Sleeping
> >> 
> >> 2015/07/18 12:16:16 akmods: Could not install newly built RPMs. You can
> >> find them and the logfile 2015/07/18 12:16:16 akmods:
> >> 346.72-2.1-for-4.0.8-300.fc22.x86_64.failed.log
> >> in /var/cache/akmods/nvidia/ Looking in the journal shows dnf-makecache
> >> running at the time that akmods.service need RPMDB access.
> >> 
> >> I ended up working around the issue with:
> >>          systemctl disable dnf-makecache.service
> >>          systemctl disable dnf-makecache.timer
> >> 
> >> I'm not sure what the right systemd unit change will be to have a
> >> reliable start up. How do you prevent dnf-makecache from running
> >> until after akmods.service has run given that started off a timer?
> >> 
> >> At the next kernel release I'll know if this is successful