Re: [Intel-gfx] i915 monitor hotplug on 4.1/4.4 PREEMPT
On Fri, Oct 21, 2016 at 04:21:53PM +0300, Nicolae Rosia wrote: > Hello, > > On Fri, Oct 21, 2016 at 3:27 PM, Daniel Vetterwrote: > > So yeah, "upgrade" is very likely is. > I see... > > i915.disable_power_well=0 seems to do the trick. > Is it safe to use? The kernel gets tainted because of this. We taint the kernel on principle if you touch any of these debug options, i.e. don't send us bug reports if it blows up. Because it'll be running untested codepaths. -Daniel -- Daniel Vetter Software Engineer, Intel Corporation http://blog.ffwll.ch ___ Intel-gfx mailing list Intel-gfx@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/intel-gfx
Re: [Intel-gfx] i915 monitor hotplug on 4.1/4.4 PREEMPT
Hello, On Fri, Oct 21, 2016 at 3:27 PM, Daniel Vetterwrote: > So yeah, "upgrade" is very likely is. I see... i915.disable_power_well=0 seems to do the trick. Is it safe to use? The kernel gets tainted because of this. Regards, Nicolae ___ Intel-gfx mailing list Intel-gfx@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/intel-gfx
Re: [Intel-gfx] i915 monitor hotplug on 4.1/4.4 PREEMPT
On Thu, Oct 20, 2016 at 05:09:52PM +0300, Nicolae Rosia wrote: > Hi, > > On Thu, Oct 20, 2016 at 3:57 PM, David Weinehallwrote: > >> > I get an udev event for unplugging, but there's no event generated for > >> > plugging the monitor back in. > >> > >> Does it work on non-RT? Does it work on v4.8 or v4.9-rc1? > > > > The second one is relevant though. 4.1 is pre-historic, 4.4 is ancient. > I just tested this on v4.8.2-rt2 and it works. > > Any tips on what I should do next, excluding the upgrade :-) ? Very, very likely the answer is "upgrade", because: $ git log --oneline v4.4..v4.8 -- drivers/gpu/drm/i915/ | wc -l 1931 That's not even counting the drm core changes, which also might be relevant. Normally a revert bisect (to figure out the bugfix, hoping that it's just 1 patch and not an entire series) would be an option. But since -rt is still an add-on you'd need to rebase the entire -rt patchset every time. That's impossible. If you have way too much time, and know what you're doing another option might be to backport all of drm (to avoid conflicts between drm core and i915) from 4.8 to 4.4. No guarantee at all it'll work, and we generally keep a few people busy for a while every time we have to do that internally for some product team. So yeah, "upgrade" is very likely is. -Daniel -- Daniel Vetter Software Engineer, Intel Corporation http://blog.ffwll.ch ___ Intel-gfx mailing list Intel-gfx@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/intel-gfx
Re: [Intel-gfx] i915 monitor hotplug on 4.1/4.4 PREEMPT
Hi, On Thu, Oct 20, 2016 at 3:57 PM, David Weinehallwrote: >> > I get an udev event for unplugging, but there's no event generated for >> > plugging the monitor back in. >> >> Does it work on non-RT? Does it work on v4.8 or v4.9-rc1? > > The second one is relevant though. 4.1 is pre-historic, 4.4 is ancient. I just tested this on v4.8.2-rt2 and it works. Any tips on what I should do next, excluding the upgrade :-) ? Best regards, Nicolae ___ Intel-gfx mailing list Intel-gfx@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/intel-gfx
Re: [Intel-gfx] i915 monitor hotplug on 4.1/4.4 PREEMPT
On Thu, 20 Oct 2016, David Weinehallwrote: > On Thu, Oct 20, 2016 at 03:28:10PM +0300, Jani Nikula wrote: >> On Thu, 20 Oct 2016, Nicolae Rosia wrote: >> > Monitor hotplugging seems to be broken on latest 4.1/4.4 RT kernel with >> > i915. >> > I have tested this on non-RT kernel and it works. > > The answer to your first question seems to be here :) *blush* >> > I get an udev event for unplugging, but there's no event generated for >> > plugging the monitor back in. >> >> Does it work on non-RT? Does it work on v4.8 or v4.9-rc1? > > The second one is relevant though. 4.1 is pre-historic, 4.4 is ancient. I think the honest answer here is that we do not have the resources to debug RT vs. non-RT issues all that much in general, and especially not for such old kernels. RT is not in our focus, and hotplug has proved to be hard enough on non-RT. Nothing to be proud of, but we have 500+ bugs open over at the freedesktop.org bugzilla, most for relatively recent non-RT kernels. Even if we fixed this upstream (and it would have to be fixed upstream to be backported) it's a huge problem that the feedback loop for RT kernels has such a long delay. If we break something for RT, it takes forever for us to find out. BR, Jani. -- Jani Nikula, Intel Open Source Technology Center ___ Intel-gfx mailing list Intel-gfx@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/intel-gfx
Re: [Intel-gfx] i915 monitor hotplug on 4.1/4.4 PREEMPT
On Thu, Oct 20, 2016 at 03:28:10PM +0300, Jani Nikula wrote: > On Thu, 20 Oct 2016, Nicolae Rosiawrote: > > Monitor hotplugging seems to be broken on latest 4.1/4.4 RT kernel with > > i915. > > I have tested this on non-RT kernel and it works. The answer to your first question seems to be here :) > > I get an udev event for unplugging, but there's no event generated for > > plugging the monitor back in. > > Does it work on non-RT? Does it work on v4.8 or v4.9-rc1? The second one is relevant though. 4.1 is pre-historic, 4.4 is ancient. Kind regards, David ___ Intel-gfx mailing list Intel-gfx@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/intel-gfx
Re: [Intel-gfx] i915 monitor hotplug on 4.1/4.4 PREEMPT
On Thu, 20 Oct 2016, Nicolae Rosiawrote: > Monitor hotplugging seems to be broken on latest 4.1/4.4 RT kernel with i915. > I have tested this on non-RT kernel and it works. > I get an udev event for unplugging, but there's no event generated for > plugging the monitor back in. Does it work on non-RT? Does it work on v4.8 or v4.9-rc1? BR, Jani. -- Jani Nikula, Intel Open Source Technology Center ___ Intel-gfx mailing list Intel-gfx@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/intel-gfx