On Sun, 2016-09-18 at 13:35 +0200, Thorsten Leemhuis wrote: > Hi! James & Paulo: What's the current status of this? No, the only interaction has been the suggestion below for a revert, which didn't fix the problem. > Was this issue discussed elsewhere or even fixed in between? Just > asking, because this issue is on the list of regressions for 4.8. I'm just about to try out -rc7, but it's not fixed so far. James > Ciao, Thorsten > > On 01.09.2016 00:25, James Bottomley wrote: > > On Wed, 2016-08-31 at 21:51 +0000, Zanoni, Paulo R wrote: > > > Em Qua, 2016-08-31 às 14:43 -0700, James Bottomley escreveu: > > > > On Wed, 2016-08-31 at 11:23 -0700, James Bottomley wrote: > > > > > On Fri, 2016-08-26 at 09:10 -0400, James Bottomley wrote: > > > > > > We seem to have an xrandr regression with skylake now. > > > > > > What's > > > > > > happening is that I can get output on to a projector, but > > > > > > the > > > > > > system is losing video when I change the xrandr sessions > > > > > > (like > > > > > > going from a --above b to a --same-as b). The main screen > > > > > > goes > > > > > > blank, which is basically a reboot situation. > > > > > > Unfortunately, I > > > > > > can't seem to get the logs out of systemd to see if there > > > > > > was a > > > > > > dump to dmesg (the system was definitely responding). > > > > > > > > > > > > I fell back to 4.6.2 which worked perfectly, so this is > > > > > > definitely > > > > > > some sort of regression. I'll be able to debug more fully > > > > > > when > > > > > > I > > > > > > get back home from the Linux Security Summit. > > > > > > > > > > I'm home now. Unfortunately, my monitor isn't as problematic > > > > > as > > > > > the > > > > > projector, but by flipping between various modes and > > > > > separating > > > > > and > > > > > overlaying the panels with --above and --same-as (xrandr), I > > > > > can > > > > > eventually get it to the point where the main LCD panel goes > > > > > black > > > > > and can only be restarted by specifying a different mode. > > > > > > > > > > This seems to be associated with these lines in the X > > > > > > > > > > [ 14714.389] (EE) intel(0): failed to set mode: Invalid > > > > > argument > > > > > [22] > > > > > > > > > > But the curious thing is that even if this fails with the > > > > > error > > > > > message once, it may succeed a second time, so it looks to be > > > > > a > > > > > transient error translation problem from the kernel driver. > > > > > > > > > > I've attached the full log below. > > > > > > > > > > This is only with a VGA output. I currently don't have a > > > > > HDMI > > > > > dongle, but I'm in the process of acquiring one. > > > > > > > > After more playing around, I'm getting thousands of these in > > > > the > > > > kernel > > > > log (possibly millions: the log wraps very fast): > > > > > > > > [23504.873606] [drm:intel_dp_start_link_train [i915]] *ERROR* > > > > failed > > > > to train DP, aborting > > > > > > > > And then finally it gives up with > > > > > > > > [25023.770951] [drm:intel_cpu_fifo_underrun_irq_handler [i915]] > > > > *ERROR* CPU pipe B FIFO underrun > > > > [25561.926075] [drm:intel_cpu_fifo_underrun_irq_handler [i915]] > > > > *ERROR* CPU pipe A FIFO underrun > > > > > > > > And the crtc for the VGA output becomes non-responsive to any > > > > configuration command. This requires a reboot and sometimes a > > > > UEFI > > > > variable reset before it comes back. > > > > > > Please see this discussion: > > > https://patchwork.freedesktop.org/patch/103237/ > > > > > > Do you have this patch on your tree? Does the problem go away if > > > you > > > revert it? > > > > Yes, I've got it, it went in in 4.8-rc3 according to git: > > > > commit 58e311b09c319183254d9220c50a533e7157c9ab > > Author: Matt Roper <matthew.d.roper@xxxxxxxxx> > > Date: Thu Aug 4 14:08:00 2016 -0700 > > > > drm/i915/gen9: Give one extra block per line for SKL plane WM > > calculations > > > > Reverting it causes the secondary display not to sync pretty much > > at > > all. However, in the flickers I can see, it does work OK and > > doesn't > > now crash switching from --same-as to --above and back > > > > I also still get the logs filling up with the link training errors. > > > > On balance, although the behaviour is different, it's not an > > improvement because if I can't sync with the projector, I can't > > really > > use this as a fix. > > > > James > _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel