Re: [lkp] [drm/i915] 396e33ae20: [drm:intel_set_cpu_fifo_underrun_reporting [i915]] *ERROR* uncleared fifo underrun on pipe B

[William Dauchy <wdauchy@gmail.com>]

On Mon, Jan 11, 2016 at 2:35 AM, kernel test robot
<ying.huang@linux.intel.com> wrote:
> FYI, we noticed the below changes on
>
> git://anongit.freedesktop.org/drm-intel drm-intel-next-queued
> commit 396e33ae204f52abebec9e578f44c749305500f4 ("drm/i915: Add two-stage ILK-style watermark programming (v10)")
>
>
> +--------------------------------------------------+------------+------------+
> |                                                  | 2dfb0b816d | 396e33ae20 |
> +--------------------------------------------------+------------+------------+
> | boot_successes                                   | 8          | 19         |
> | boot_failures                                    | 0          | 4          |
> | drm:intel_set_cpu_fifo_underrun_reporting[i915]] | 0          | 4          |
> | drm:intel_cpu_fifo_underrun_irq_handler[i915]]   | 0          | 4          |
> | drm:intel_set_pch_fifo_underrun_reporting[i915]] | 0          | 4          |
> | drm:intel_pch_fifo_underrun_irq_handler[i915]]   | 0          | 4          |
> +--------------------------------------------------+------------+------------+
>
>
>
> [   36.077826] NFS: Registering the id_resolver key type
> [   36.078178] Key type id_resolver registered
> [   36.078444] Key type id_legacy registered
> [   60.884026] [drm:intel_set_cpu_fifo_underrun_reporting [i915]] *ERROR* uncleared fifo underrun on pipe B
> [   60.884659] [drm:intel_cpu_fifo_underrun_irq_handler [i915]] *ERROR* CPU pipe B FIFO underrun
> [   60.885221] [drm:intel_set_pch_fifo_underrun_reporting [i915]] *ERROR* uncleared pch fifo underrun on pch transcoder B
> [   60.885887] [drm:intel_pch_fifo_underrun_irq_handler [i915]] *ERROR* PCH transcoder B FIFO underrun
> [   61.180651] random: nonblocking pool is initialized
> [   81.430503] [drm:intel_set_cpu_fifo_underrun_reporting [i915]] *ERROR* uncleared fifo underrun on pipe C
> [   81.431193] [drm:intel_cpu_fifo_underrun_irq_handler [i915]] *ERROR* CPU pipe C FIFO underrun
> [   81.431782] [drm:intel_set_pch_fifo_underrun_reporting [i915]] *ERROR* uncleared pch fifo underrun on pch transcoder C
> [   81.432474] [drm:intel_pch_fifo_underrun_irq_handler [i915]] *ERROR* PCH transcoder C FIFO underrun
>
>
> To reproduce:
>
>         git clone git://git.kernel.org/pub/scm/linux/kernel/git/wfg/lkp-tests.git
>         cd lkp-tests
>         bin/lkp install job.yaml  # job file is attached in this email
>         bin/lkp run     job.yaml

I am still triggering these errors on v4.4.6
Does anybody knows if there is a fix in queue? What can I do to help
debug this issue?

Thanks,
-- 
William