#1076708 short screen blackouts on intel iris+ 640 gpu when watching videos, reports of CPU pipe FIFO underrun errors from i915 module in logs

Package:
src:linux
Source:
src:linux
Submitter:
Piotr Morgwai Kotarbinski
Date:
2025-07-30 10:33:01 UTC
Severity:
normal
Tags:
#1076708#5
Date:
2024-07-22 10:48:21 UTC
From:
To:
So far happened only when watching videos (vlc, web), most usually in full-
screen mode, but there have been a few non-full-screen occurrences as well.
Blackouts last around 0.5-1.5s and seem to be happening quite randomly:
sometimes I'm able to watch a 2 hours video without a single incident, then
when rewatching the same video it happens every 2 minutes. After each blackout
there *always* appears an entry in logs like the below:
kernel: i915 0000:00:02.0: [drm] *ERROR* CPU pipe X FIFO underrun
...where 'X' is either 'A' or 'B'.

I switched from Ubuntu-18.04 on the same hardware few months ago and on the
previous system this problem has never happened.
I've installed fully upgraded Ubuntu-24.04 on a separate drive and there I
could not reproduce the problem (although I watched just 2 45-minute videos, so
given the randomness of occurrences, this does not completely exclude the bug
being present there as well).
I've also installed fully upgraded Debian Bookworm on a separate drive and
there the problem DID occur.

I usually use an external display (please find xrandr.txt file attached with
the output of `xrandr --verbose`), so today I've tried to watch few videos on
my laptop's internal display and I was not able to reproduce the problem (but
again given the randomness it should be taken with a grain of salt).

The problem has occurred on all versions of Trixie kernel that I've run so far:
6.7.12, 6.9.7, 6.9.8, 6.9.9. Attached please find the output of `last reboot`
and `journalctl |grep i915` in files last-reboot.txt and i915.log respectively.

#1076708#10
Date:
2024-07-23 13:50:18 UTC
From:
To:
Just in case I've just verified that the issue occurs both when watching videos with codecs that are and are not hardware-supportted by my GPU.

Nevertheless in case it matters I have the following video-related packages installed:
intel-media-va-driver:amd64 24.2.5+dfsg1-1
intel-media-va-driver:i386 24.2.5+dfsg1-1
i965-va-driver:amd64 2.4.1+dfsg1-1
i965-va-driver:i386 2.4.1+dfsg1-1
firmware-intel-graphics 20240610-1

the following packages are NOT installed:
intel-media-va-driver-non-free
i965-va-driver-shaders

LIBVA_DRIVER_NAME env var is NOT defined



vlc has "Hardware-accelerated decoding" set to "Automatic"
When playing videos with H264 codec `intel_gpu_top` shows that the video engine is being used, for all other codecs it is idle.



Firefox config has been modified according to https://wiki.debian.org/Firefox#Hardware_Video_Acceleration instructions:

launcher is defined as the below:
Exec=env MOZ_X11_EGL=1 /usr/lib/firefox-esr/firefox-esr %u

related config variables are defined as follows:
media.ffmpeg.vaapi.enabled true
media.ffvpx.enabled false
media.av1.enabled false

I have verified with `intel_gpu_top` that the video engine is being used when watching videos in Firefox.

When I was trying to reproduce the bug on Ubuntu-24.04 I modified the config the same way and also verified with intel_gpu_top that the video engine was active.



vainfo output:
libva info: VA-API version 1.22.0
libva info: Trying to open /usr/lib/x86_64-linux-gnu/dri/iHD_drv_video.so
libva info: Found init function __vaDriverInit_1_22
libva info: va_openDriver() returns 0
vainfo: VA-API version: 1.22 (libva 2.12.0)
vainfo: Driver version: Intel iHD driver for Intel(R) Gen Graphics - 24.2.5 ()
vainfo: Supported profile and entrypoints
      VAProfileMPEG2Simple            :	VAEntrypointVLD
      VAProfileMPEG2Main              :	VAEntrypointVLD
      VAProfileH264Main               :	VAEntrypointVLD
      VAProfileH264Main               :	VAEntrypointEncSliceLP
      VAProfileH264High               :	VAEntrypointVLD
      VAProfileH264High               :	VAEntrypointEncSliceLP
      VAProfileJPEGBaseline           :	VAEntrypointVLD
      VAProfileJPEGBaseline           :	VAEntrypointEncPicture
      VAProfileH264ConstrainedBaseline:	VAEntrypointVLD
      VAProfileH264ConstrainedBaseline:	VAEntrypointEncSliceLP
      VAProfileVP8Version0_3          :	VAEntrypointVLD
      VAProfileHEVCMain               :	VAEntrypointVLD
      VAProfileHEVCMain10             :	VAEntrypointVLD
      VAProfileVP9Profile0            :	VAEntrypointVLD
      VAProfileVP9Profile2            :	VAEntrypointVLD



vdpauinfo output:
display: :0   screen: 0
libva info: VA-API version 1.22.0
libva info: Trying to open /usr/lib/x86_64-linux-gnu/dri/iHD_drv_video.so
libva info: Found init function __vaDriverInit_1_22
libva info: va_openDriver() returns 0
API version: 1
Information string: OpenGL/VAAPI backend for VDPAU

Video surface:

name   width height types
-------------------------------------------
420     4096  4096  NV12 YV12 UYVY YUYV Y8U8V8A8 V8U8Y8A8 NV24 YV24 P010 P016 Y_U_V_444_16
422     4096  4096  NV12 YV12 UYVY YUYV Y8U8V8A8 V8U8Y8A8 NV24 YV24 P010 P016 Y_U_V_444_16
444     4096  4096  NV12 YV12 UYVY YUYV Y8U8V8A8 V8U8Y8A8 NV24 YV24 P010 P016 Y_U_V_444_16
420_16  4096  4096  NV12 YV12 UYVY YUYV Y8U8V8A8 V8U8Y8A8 NV24 YV24 P010 P016 Y_U_V_444_16
422_16  4096  4096  NV12 YV12 UYVY YUYV Y8U8V8A8 V8U8Y8A8 NV24 YV24 P010 P016 Y_U_V_444_16
444_16  4096  4096  NV12 YV12 UYVY YUYV Y8U8V8A8 V8U8Y8A8 NV24 YV24 P010 P016 Y_U_V_444_16

Decoder capabilities:

name                        level macbs width height
----------------------------------------------------
MPEG1                          --- not supported ---
MPEG2_SIMPLE                   --- not supported ---
MPEG2_MAIN                     --- not supported ---
H264_BASELINE                  51 16384  2048  2048
H264_MAIN                      51 16384  2048  2048
H264_HIGH                      51 16384  2048  2048
VC1_SIMPLE                     --- not supported ---
VC1_MAIN                       --- not supported ---
VC1_ADVANCED                   --- not supported ---
MPEG4_PART2_SP                 --- not supported ---
MPEG4_PART2_ASP                --- not supported ---
DIVX4_QMOBILE                  --- not supported ---
DIVX4_MOBILE                   --- not supported ---
DIVX4_HOME_THEATER             --- not supported ---
DIVX4_HD_1080P                 --- not supported ---
DIVX5_QMOBILE                  --- not supported ---
DIVX5_MOBILE                   --- not supported ---
DIVX5_HOME_THEATER             --- not supported ---
DIVX5_HD_1080P                 --- not supported ---
H264_CONSTRAINED_BASELINE      51 16384  2048  2048
H264_EXTENDED                  --- not supported ---
H264_PROGRESSIVE_HIGH          --- not supported ---
H264_CONSTRAINED_HIGH          --- not supported ---
H264_HIGH_444_PREDICTIVE       --- not supported ---
VP9_PROFILE_0                  --- not supported ---
VP9_PROFILE_1                  --- not supported ---
VP9_PROFILE_2                  --- not supported ---
VP9_PROFILE_3                  --- not supported ---
HEVC_MAIN                      --- not supported ---
HEVC_MAIN_10                   --- not supported ---
HEVC_MAIN_STILL                --- not supported ---
HEVC_MAIN_12                   --- not supported ---
HEVC_MAIN_444                  --- not supported ---
HEVC_MAIN_444_10               --- not supported ---
HEVC_MAIN_444_12               --- not supported ---
AV1_MAIN                       --- not supported ---
AV1_HIGH                       --- not supported ---
AV1_PROFESSIONAL               --- not supported ---

Output surface:

name              width height nat types
----------------------------------------------------
B8G8R8A8         16384 16384    y
R8G8B8A8         16384 16384    y
R10G10B10A2      16384 16384    y
B10G10R10A2      16384 16384    y
A8               16384 16384    y

Bitmap surface:

name              width height
------------------------------
B8G8R8A8         16384 16384
R8G8B8A8         16384 16384
R10G10B10A2      16384 16384
B10G10R10A2      16384 16384
A8               16384 16384

Video mixer:

feature name                    sup
------------------------------------
DEINTERLACE_TEMPORAL             -
DEINTERLACE_TEMPORAL_SPATIAL     -
INVERSE_TELECINE                 -
NOISE_REDUCTION                  -
SHARPNESS                        -
LUMA_KEY                         -
HIGH QUALITY SCALING - L1        -
HIGH QUALITY SCALING - L2        -
HIGH QUALITY SCALING - L3        -
HIGH QUALITY SCALING - L4        -
HIGH QUALITY SCALING - L5        -
HIGH QUALITY SCALING - L6        -
HIGH QUALITY SCALING - L7        -
HIGH QUALITY SCALING - L8        -
HIGH QUALITY SCALING - L9        -

parameter name                  sup      min      max
-----------------------------------------------------
VIDEO_SURFACE_WIDTH              -
VIDEO_SURFACE_HEIGHT             -
CHROMA_TYPE                      -
LAYERS                           -

attribute name                  sup      min      max
-----------------------------------------------------
BACKGROUND_COLOR                 -
CSC_MATRIX                       -
NOISE_REDUCTION_LEVEL            -
SHARPNESS_LEVEL                  -
LUMA_KEY_MIN_LUMA                -
LUMA_KEY_MAX_LUMA                -

#1076708#15
Date:
2024-07-27 21:22:48 UTC
From:
To:
I've just replicated this bug on Ubuntu-24.04 (kernel 6.8.0-39-generic), so it seems to be an upstream bug rather than a Debian specific.
#1076708#20
Date:
2024-08-22 21:50:01 UTC
From:
To:
This seems to be the same or a very similar issue as posted here:
https://gitlab.freedesktop.org/drm/i915/kernel/-/issues/5455
I will be posting further updates there.

#1076708#25
Date:
2025-05-01 16:01:50 UTC
From:
To:
Hi

This bug was filed for a (very) old kernel or the bug is old itself
without resolution. Maybe it was for a feature enablement which nobody
acted on. We are sorry we were not able to timely deal with this issue.
There are many open bugs for the src:linux package and thus we are
closing older bugs where it's unclear if they still occur in newer
versions and are still relevant to the reporter. For an overview see:
https://bugs.debian.org/src:linux .

If you can reproduce your issue with

- the current version in unstable/testing
- the latest kernel from backports

or, if it was a feature addition/wishlist and still consider it
relevant, then:

Please reopen the bug, see https://www.debian.org/Bugs/server-control
for details.

Please try to provide as much fresh details including kernel logs where
relevant. In particular were an issue is coupled with specific hardware we
might ask you to do additional debugging on your side as the owner of the
hardware.

Regards,
Salvatore

#1076708#28
Date:
2025-05-01 16:01:50 UTC
From:
To:
Hi

This bug was filed for a (very) old kernel or the bug is old itself
without resolution. Maybe it was for a feature enablement which nobody
acted on. We are sorry we were not able to timely deal with this issue.
There are many open bugs for the src:linux package and thus we are
closing older bugs where it's unclear if they still occur in newer
versions and are still relevant to the reporter. For an overview see:
https://bugs.debian.org/src:linux .

If you can reproduce your issue with

- the current version in unstable/testing
- the latest kernel from backports

or, if it was a feature addition/wishlist and still consider it
relevant, then:

Please reopen the bug, see https://www.debian.org/Bugs/server-control
for details.

Please try to provide as much fresh details including kernel logs where
relevant. In particular were an issue is coupled with specific hardware we
might ask you to do additional debugging on your side as the owner of the
hardware.

Regards,
Salvatore

#1076708#33
Date:
2025-05-12 07:18:39 UTC
From:
To:
Hi and sorry for the delay: I was traveling until recently and didn't have a full access to the hardware in question.

This bug is still present in kernel 6.12 and 6.14 (I've experienced it during last few days when using 6.12.25-1, 6.12.27-1, 6.14.5-1~exp1 and 6.14.6-1~exp1 on trixie).

Generally please refer to the mentioned upstream bug https://gitlab.freedesktop.org/drm/i915/kernel/-/issues/5455 : this bug should probably not be closed until the upstream one is. I hope to find some time this week to try to replicate it using drm-tip kernel as requested by the upstream maintainers.

Cheers!

#1076708#48
Date:
2025-07-17 01:54:40 UTC
From:
To:
Hello Piotr,

This upstream bug was closed recently as it's not reproducible for the
original reporter on 6.15.4.

Can you please test this (or a newer) kernel version an confirm? 6.15.4
is in experimental which should make this easy.

Best regards
Uwe

#1076708#55
Date:
2025-07-30 10:31:46 UTC
From:
To:
Note that in the meantime the bug was reopened again. This doesn't make
retesting on 6.15 useless, as that would at least result in a bump for
upstream that the issue is still relevant for more than one person.

Best regards
Uwe