From mboxrd@z Thu Jan 1 00:00:00 1970 From: Daniel Vetter Subject: Re: [Intel-gfx] i915 monitor hotplug on 4.1/4.4 PREEMPT Date: Fri, 21 Oct 2016 14:27:56 +0200 Message-ID: <20161021122756.GY20761@phenom.ffwll.local> References: <87r37bqk6d.fsf@intel.com> <20161020125708.GB8202@suiko.acc.umu.se> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: David Weinehall , dri-devel@lists.freedesktop.org, intel-gfx@lists.freedesktop.org, "linux-rt-users@vger.kernel.org" To: Nicolae Rosia Return-path: Received: from mail-lf0-f65.google.com ([209.85.215.65]:34274 "EHLO mail-lf0-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755228AbcJUM2A (ORCPT ); Fri, 21 Oct 2016 08:28:00 -0400 Received: by mail-lf0-f65.google.com with SMTP id x23so5418683lfi.1 for ; Fri, 21 Oct 2016 05:28:00 -0700 (PDT) Content-Disposition: inline In-Reply-To: Sender: linux-rt-users-owner@vger.kernel.org List-ID: On Thu, Oct 20, 2016 at 05:09:52PM +0300, Nicolae Rosia wrote: > Hi, > > On Thu, Oct 20, 2016 at 3:57 PM, David Weinehall wrote: > >> > 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