On Sun, 2 Feb 2020 16:02:18 +0100, Christian Zigotzky wrote: > On 02 February 2020 at 09:19 am, Christophe Leroy wrote: > > Hello, > > > > Le 02/02/2020 à 01:08, Christian Zigotzky a écrit : > >> Hello, > >> > >> We regularly compile and test Linux kernels every day during the > >> merge window. Since Thuesday we have very high CPU loads because of > >> the avahi daemon on our desktop Linux systems (Ubuntu, Debian etc). > >> > >> Error message: avahi-daemon[2410]: ioctl(): Inappropriate ioctl for > >> device > > > > Do you know which ioctl, on which device ? > > Can you take a trace of running avahi-daemon with 'strace' ? > > > > Can you bisect ? > > > > Christophe > Hi Christophe, > Hi All, > > I figured out that the avahi-daemon has a problem with the IPv6 address > of a network interface since the Git kernel from Thursday. (Log attached) > This generates high CPU usage because the avahi-daemon tries to access > the IPv6 address again and again and thereby it produces a lot of log > messages. > > We figured out that the networking updates aren't responsible for this > issue because we created a test kernel on Wednesday. The issue is > somewhere in the commits from Wednesday night to Thursday (CET). FWIW Thursday is when the latest networking pull came in, so could well be networking related.. > Please compile the latest Git kernel and test it with a desktop linux > distribution for example Ubuntu. In my point of view there are many > desktop machines affected. Many server systems don't use the avahi > daemon so they aren't affected. > > It's possible to deactivate the access to the IPv6 address with the > following line in the file "/etc/avahi/avahi-daemon.conf": > > use-ipv6=no > > After a reboot the CPU usage is normal again. This is only a temporary > solution. > > Unfortunately I don't have the time for bisecting next week. I have a > lot of other work to do. In my point of view it is very important that > you also compile the latest Git kernels. Then you will see the issue and > then you have a better possibility to fix the issue.
