On Tue, 12 Mar 2013 19:57:30 +0200 Konstantin Belousov wrote: > On Tue, Mar 12, 2013 at 04:53:25PM +0000, Max Brazhnikov wrote: > > On Fri, 08 Mar 2013 11:38:13 -0800 Kevin Oberman wrote: > > > On Fri, Mar 8, 2013 at 10:03 AM, Max Brazhnikov <m...@freebsd.org> wrote: > > > > PID USERNAME THR PRI NICE SIZE RES STATE C TIME WCPU > > > > COMMAND > > > > 11 root 2 155 ki31 0K 32K RUN 1 4:16 120.35% > > idle > > > > 12 root 18 -84 - 0K 288K WAIT 0 0:57 76.34% > > > > intr > > > > > > > > I've got this after second boot today, although I couldn't reproduce it > > > > yesterday even after ten attempts. But sometimes it's quite nasty and I > > > > have > > > > to reboot the system several times to get rid of it. > > > > > > > > Max > > > > > > > > > > So the issue is that that the interrupts from one or another of the USB > > > devices has exploded from near zero to around 40K when the kernel module > > > is > > > loaded? > > > > Exactly. > > > > > A couple of possibly irrelevant questions. Do you normally manually load > > > the module? I did not research the issue, but when I manually load the > > > module I was seeing things just grind to a halt. If I started Gnome, the > > > module was loaded automatically by X, and things worked. > > > > No I don't usually load it manually, I was just wondering what causes the > > interrupt storm. > > > > > Why loading the Intel KMS module would cause a massive increase in > > > interrupts on a USB interface completely baffles me, but I suspect some > > > sort of race is going on when the module is pre-loaded. > > > > It happens if I allow X to load the module also, the problem is not due to > > pre-loading. > > As I said earlier, change in the userspace cannot change the interrupt > routing. What could happen (with very low probability) is that some > kind of display interrupt get aliased to the non-msi one. Since it is > unacknowledged, it causes the storm on the legacy irq line. But I never > saw this on G[M]4*. > > Just as the blind shot, try to set hw.drm.msi=0 in the loader.conf > or using the kenv, before the i915kms module is loaded.
Nice shot, it does make the difference! I've never seen the problem after adding hw.drm.msi=0 to the loader.conf. Max _______________________________________________ email@example.com mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-usb To unsubscribe, send any mail to "freebsd-usb-unsubscr...@freebsd.org"