Re: [Intel-gfx] [git pull] drm fixes

Daniel Vetter
2015-03-24T16:47:57Z

On Tue, Mar 24, 2015 at 05:48:31PM +0100, Daniel Vetter wrote:
> On Tue, Mar 24, 2015 at 12:10:28PM -0400, Josh Boyer wrote:
> > On Tue, Mar 24, 2015 at 10:46 AM, Josh Boyer <jwboyer@fedoraproject.org> wrote:
> > > On Tue, Mar 24, 2015 at 10:34 AM, Daniel Vetter <daniel@ffwll.ch> wrote:
> > >> On Tue, Mar 24, 2015 at 10:22:30AM -0400, Josh Boyer wrote:
> > >>> On Tue, Mar 24, 2015 at 9:57 AM, Josh Boyer <jwboyer@fedoraproject.org> wrote:
> > >>> > On Tue, Mar 24, 2015 at 9:40 AM, Daniel Vetter <daniel@ffwll.ch> wrote:
> > >>> >> On Tue, Mar 24, 2015 at 09:15:32AM -0400, Josh Boyer wrote:
> > >>> >>> On Tue, Mar 24, 2015 at 3:32 AM, Daniel Vetter <daniel@ffwll.ch> wrote:
> > >>> >>> > On Mon, Mar 23, 2015 at 02:34:27PM -0400, Josh Boyer wrote:
> > >>> >>> >> On Mon, Mar 23, 2015 at 11:33 AM, Josh Boyer <jwboyer@fedoraproject.org> wrote:
> > >>> >>> >>
> > >>> >>> >> <snip>
> > >>> >>> >>
> > >>> >>> >> >> Xi Ruoyao (1):
> > >>> >>> >> >> drm/i915: Ensure plane->state->fb stays in sync with plane->fb
> > >>> >>> >>
> > >>> >>> >> Turns out to be that commit.
> > >>> >>> >>
> > >>> >>> >> git bisect start 'drivers/gpu/drm/i915/'
> > >>> >>> >> # good: [b314acaccd7e0d55314d96be4a33b5f50d0b3344] Merge branch
> > >>> >>> >> 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input
> > >>> >>> >> git bisect good b314acaccd7e0d55314d96be4a33b5f50d0b3344
> > >>> >>> >> # bad: [bc465aa9d045feb0e13b4a8f32cc33c1943f62d6] Linux 4.0-rc5
> > >>> >>> >> git bisect bad bc465aa9d045feb0e13b4a8f32cc33c1943f62d6
> > >>> >>> >> # bad: [319c1d420a0b62d9dbb88104afebaabc968cdbfa] drm/i915: Ensure
> > >>> >>> >> plane->state->fb stays in sync with plane->fb
> > >>> >>> >> git bisect bad 319c1d420a0b62d9dbb88104afebaabc968cdbfa
> > >>> >>> >> # first bad commit: [319c1d420a0b62d9dbb88104afebaabc968cdbfa]
> > >>> >>> >> drm/i915: Ensure plane->state->fb stays in sync with plane->fb
> > >>> >>> >>
> > >>> >>> >> Doing a straight revert on top of 4.0-rc5 makes things work again,
> > >>> >>> >> albeit with the WARN_ON(obj->frontbuffer_bits) splat still being
> > >>> >>> >> there.
> > >>> >>> >
> > >>> >>> > Can you please test the tip of drm-fixes:
> > >>> >>> >
> > >>> >>> > commit 8218c3f4df3bb1c637c17552405039a6dd3c1ee1
> > >>> >>> > Author: Daniel Vetter <daniel.vetter@ffwll.ch>
> > >>> >>> > Date: Fri Feb 27 12:58:13 2015 +0100
> > >>> >>> >
> > >>> >>> > drm: Fixup racy refcounting in plane_force_disable
> > >>> >>> >
> > >>> >>> > http://cgit.freedesktop.org/~airlied/linux/commit/?h=drm-fixes&id=8218c3f4df3bb1c637c17552405039a6dd3c1ee1
> > >>> >>> >
> > >>> >>> > Because fumble that patch didn't make it to drm-fixes a while ago and
> > >>> >>> > instead landed in drm-next.
> > >>> >>>
> > >>> >>> That seems to have helped with totally different issues a macbook I
> > >>> >>> have was seeing. However, it still doesn't fix the issue with the
> > >>> >>> Celeron based NUC machine.
> > >>> >>>
> > >>> >>> I built a kernel based on Linus' latest tree as of this morning,
> > >>> >>> without reverting 319c1d4 and adding the commit you pointed to. The
> > >>> >>> NUC still won't boot without HDMI connected. With HDMI connected I
> > >>> >>> still see the trace below. If I do the blacklist and then insmod
> > >>> >>> dance with HDMI unplugged it shows the same spew I reported yesterday
> > >>> >>> which starts with the same backtrace.
> > >>> >>>
> > >>> >>> I'll try building a kernel with 319c1d4 reverted + your patch. I
> > >>> >>> suspect things will work fine with that combination because the two
> > >>> >>> issues are unrelated.
> > >>> >>
> > >>> >> Can you please boot with drm.debug=0xff for the below case and grab
> > >>> >> complete dmesg? There'll be a lot of crap in the logs, you might need to
> > >>> >> blow up the logbuf size massively. But that log should contain everything
> > >>> >> I need to figure out where that framebuffer we're blowing up on is going.
> > >>> >
> > >>> > I provided both with HDMI attached and without (via insmod). If you
> > >>> > want them emailed directly let me know, but they were large.
> > >>> >
> > >>> > Boot with drm.debug=0xff and HDMI connected:
> > >>> >
> > >>> > https://jwboyer.fedorapeople.org/pub/drm-ff-dmesg.txt
> > >>> >
> > >>> > Boot with drm.debug=0xff without HDMI connected and i915 loaded via
> > >>> > manual insmod after boot:
> > >>> >
> > >>> > https://jwboyer.fedorapeople.org/pub/drm-ff-no-hdmi-insmod.txt
> > >>>
> > >>> Here's one more from the macbook I mentioned. It's showing the same
> > >>> kref.h splat:
> > >>>
> > >>> https://jwboyer.fedorapeople.org/pub/drm-ff-macbook.txt
> > >>
> > >> Ok there's at least one fixup for which we've failed to apply when porting
> > >> the fb refcounting fix from -next. Can you please cherry-pick
> > >>
> > >> commit f55548b5af87ebfc586ca75748947f1c1b1a4a52
> > >> Author: Damien Lespiau <damien.lespiau@intel.com>
> > >> Date: Thu Feb 5 18:30:20 2015 +0000
> > >>
> > >> drm/i915: Don't try to reference the fb in get_initial_plane_config()
> > >>
> > >> From linux-next?
> > >
> > > Yes, building now. Will let you know as soon as I test it on both machines.
> >
> > OK, with that commit applied I no longer get the kref.h splat and the
> > NUC machine boots headless. I still see the backtrace below on both
> > the NUC and the macbook. I have a copy of it with drm.debug=0xff from
> > the NUC here:
> >
> > https://jwboyer.fedorapeople.org/pub/nuc-drm-debug-ff-with-fixes.txt
> >
> > Getting better at least :).
>
> Ok thanks for testing. I'll look at that one tomorrow, wasted too much
> time with trying to resurrect a few machines that should have matched the
> common parts of what goes wrong here.
>
> Jani, can you please cherry-pick the above commit to -fixes?

Actually add Jani this time around ...
-Daniel

>
> One more question: Is the frontbuffer_bits splat now also gone? That was
> the one I have no clue about, but since somewhere around 4.0-rc it started
> poppping up in a few places ... Thus far it was always the canary for some
> other bug though.
>
> Thanks, Daniel
>
> >
> > josh
> >
> > [ +0.000372] [drm] Initialized i915 1.6.0 20150130 for 0000:00:02.0 on minor 0
> > [ +0.059774] [drm] GMBUS [i915 gmbus vga] timed out, falling back to
> > bit banging on pin 2
> > [ +0.012442] fbcon: inteldrmfb (fb0) is primary device
> > [ +0.000103] ------------[ cut here ]------------
> > [ +0.000024] WARNING: CPU: 1 PID: 109 at
> > drivers/gpu/drm/drm_atomic.c:482 drm_atomic_check_only+0x33d/0x500
> > [drm]()
> > [ +0.000006] Modules linked in: i915 i2c_algo_bit drm_kms_helper drm
> > sdhci_pci sdhci mmc_core video
> > [ +0.000004] CPU: 1 PID: 109 Comm: kworker/u16:7 Not tainted
> > 4.0.0-0.rc5.git1.3.fc23.x86_64 #1
> > [ +0.000001] Hardware name: Apple Inc.
> > MacBookPro10,2/Mac-AFD8A9D944EA4843, BIOS
> > MBP102.88Z.0106.B03.1211161133 11/16/2012
> > [ +0.000005] Workqueue: events_unbound async_run_entry_fn
> > [ +0.000003] 0000000000000000 00000000cbdcc84e ffff8802628bb868
> > ffffffff8177ada9
> > [ +0.000002] 0000000000000000 0000000000000000 ffff8802628bb8a8
> > ffffffff8109c78a
> > [ +0.000002] ffff88026154c940 0000000000000048 ffff880262b1e600
> > ffff88026229e2a0
> > [ +0.000001] Call Trace:
> > [ +0.000007] [<ffffffff8177ada9>] dump_stack+0x45/0x57
> > [ +0.000003] [<ffffffff8109c78a>] warn_slowpath_common+0x8a/0xc0
> > [ +0.000003] [<ffffffff8109c8ba>] warn_slowpath_null+0x1a/0x20
> > [ +0.000014] [<ffffffffa00700ed>] drm_atomic_check_only+0x33d/0x500 [drm]
> > [ +0.000005] [<ffffffff811bc0a6>] ? kmemdup+0x36/0x50
> > [ +0.000013] [<ffffffffa00702c7>] drm_atomic_commit+0x17/0x60 [drm]
> > [ +0.000008] [<ffffffffa00c371d>]
> > drm_atomic_helper_plane_set_property+0x8d/0xd0 [drm_kms_helper]
> > [ +0.000013] [<ffffffffa005e89d>] drm_mode_plane_set_obj_prop+0x2d/0x90 [drm]
> > [ +0.000006] [<ffffffffa00c550b>] restore_fbdev_mode+0x6b/0xf0
> > [drm_kms_helper]
> > [ +0.000006] [<ffffffffa00c75c9>]
> > drm_fb_helper_restore_fbdev_mode_unlocked+0x29/0x80 [drm_kms_helper]
> > [ +0.000006] [<ffffffffa00c7642>] drm_fb_helper_set_par+0x22/0x50
> > [drm_kms_helper]
> > [ +0.000042] [<ffffffffa016959a>] intel_fbdev_set_par+0x1a/0x60 [i915]
> > [ +0.000005] [<ffffffff8140c328>] fbcon_init+0x578/0x600
> > [ +0.000005] [<ffffffff8148ceac>] visual_init+0xbc/0x120
> > [ +0.000004] [<ffffffff8148f84e>] do_bind_con_driver+0x17e/0x3b0
> > [ +0.000007] [<ffffffff8148ffd4>] do_take_over_console+0xb4/0x1b0
> > [ +0.000013] [<ffffffff81407163>] do_fbcon_takeover+0x63/0xd0
> > [ +0.000003] [<ffffffff8140ce4d>] fbcon_event_notify+0x6cd/0x7d0
> > [ +0.000005] [<ffffffff810bc18f>] notifier_call_chain+0x4f/0x80
> > [ +0.000003] [<ffffffff810bc50b>] __blocking_notifier_call_chain+0x4b/0x70
> > [ +0.000002] [<ffffffff810bc546>] blocking_notifier_call_chain+0x16/0x20
> > [ +0.000003] [<ffffffff81412dbb>] fb_notifier_call_chain+0x1b/0x20
> > [ +0.000013] [<ffffffff81415184>] register_framebuffer+0x214/0x360
> > [ +0.000007] [<ffffffffa00c78d4>]
> > drm_fb_helper_initial_config+0x264/0x3c0 [drm_kms_helper]
> > [ +0.000004] [<ffffffff810d8401>] ? pick_next_task_fair+0x121/0x8b0
> > [ +0.000034] [<ffffffffa016a89b>] intel_fbdev_initial_config+0x1b/0x20 [i915]
> > [ +0.000002] [<ffffffff810bdd1a>] async_run_entry_fn+0x4a/0x150
> > [ +0.000002] [<ffffffff810b552c>] process_one_work+0x14c/0x400
> > [ +0.000002] [<ffffffff810b5fb3>] worker_thread+0x53/0x470
> > [ +0.000003] [<ffffffff810b5f60>] ? rescuer_thread+0x300/0x300
> > [ +0.000002] [<ffffffff810b5f60>] ? rescuer_thread+0x300/0x300
> > [ +0.000002] [<ffffffff810bb1f8>] kthread+0xd8/0xf0
> > [ +0.000004] [<ffffffff810bb120>] ? kthread_create_on_node+0x1b0/0x1b0
> > [ +0.000004] [<ffffffff81781458>] ret_from_fork+0x58/0x90
> > [ +0.000003] [<ffffffff810bb120>] ? kthread_create_on_node+0x1b0/0x1b0
> > [ +0.000002] ---[ end trace a73ba186968c6ec8 ]---
>
> --
> Daniel Vetter
> Software Engineer, Intel Corporation
> http://blog.ffwll.ch

--
Daniel Vetter
Software Engineer, Intel Corporation