I also saw these logs when a video was played. Alex. Can you take a look?

Indeed these info lines are a bit too verbose. They are printed every time VA-API is initialized, typically once per video played. Let me prepare a CL downgrade them to debug.

Turns out these come from libva directly. We need to disable a configure flag to make them silent. Since https://chromium-review.googlesource.com/c/557361 is in the commit queue I will wait until it gets merged to update the ebuild.

Finally libva 1.8.3 got merged. CL is here: https://chromium-review.googlesource.com/c/chromiumos/overlays/chromiumos-overlay/+/636865

The following revision refers to this bug:
  https://chromium.googlesource.com/chromiumos/overlays/chromiumos-overlay/+/066fe0750656c2f407ec42045038ce8e71ad6af8

commit 066fe0750656c2f407ec42045038ce8e71ad6af8
Author: Alexandre Courbot <acourbot@chromium.org>
Date: Tue Aug 29 07:12:21 2017

libva: disable info messages

libva outputs by default some information messages when it is being
opened. These messages are not very useful to the end-user, and tend to
fill log buffers when video decoding is stress-tested, so disable them.

CQ-DEPEND=CL:557361
BUG= chromium:752187 
TEST=Made sure info messages were not displayed anymore with new ebuild,
and that VDA unittest still passed.

Change-Id: I3bfa8728f931f01c5a742b6f5ce5965c87c141d4
Reviewed-on: https://chromium-review.googlesource.com/636865
Commit-Ready: Alexandre Courbot <acourbot@chromium.org>
Tested-by: Alexandre Courbot <acourbot@chromium.org>
Reviewed-by: Daniel Charles <daniel.charles@intel.com>
Reviewed-by: Pawel Osciak <posciak@chromium.org>

[rename] https://crrev.com/066fe0750656c2f407ec42045038ce8e71ad6af8/x11-libs/libva/libva-1.8.3-r2.ebuild
[modify] https://crrev.com/066fe0750656c2f407ec42045038ce8e71ad6af8/x11-libs/libva/libva-1.8.3.ebuild

Should be fixed now, closing. Thanks for the report!

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/f46cd7c10a59eecbc0b5cad615b25d6f44e7cfb7

commit f46cd7c10a59eecbc0b5cad615b25d6f44e7cfb7
Author: Alexandre Courbot <acourbot@chromium.org>
Date: Thu Sep 07 06:00:51 2017

media/gpu/vaapi_wrapper: tune libva error level

All errors in vaapi_wrapper are reported with the ERROR log level,
except when vaInitialize() happens to fail. Before we address crbug
752187, error status was still reported by libva itself, but since we
disabled it libva would just fail silently.

Promote the error report in this case from WARNING to ERROR, so we get a
trace of vaInitialize() failing.

Also set the LIBVA_MESSAGING_LEVEL so libva error messages get printed.
This will still skip info-level messages.

BUG= chromium:752187 
TEST=checked that errors were properly reported when vaInitialize()
fails.

Cq-Include-Trybots: master.tryserver.chromium.android:android_optional_gpu_tests_rel;master.tryserver.chromium.linux:linux_optional_gpu_tests_rel;master.tryserver.chromium.mac:mac_optional_gpu_tests_rel;master.tryserver.chromium.win:win_optional_gpu_tests_rel
Change-Id: I19448a64c71df6ca18278981a27a4048236af16b
Reviewed-on: https://chromium-review.googlesource.com/646992
Commit-Queue: Alexandre Courbot <acourbot@chromium.org>
Reviewed-by: Dale Curtis <dalecurtis@chromium.org>
Cr-Commit-Position: refs/heads/master@{#500230}
[modify] https://crrev.com/f46cd7c10a59eecbc0b5cad615b25d6f44e7cfb7/media/gpu/vaapi_wrapper.cc

The following revision refers to this bug:
  https://chromium.googlesource.com/chromiumos/overlays/chromiumos-overlay/+/eecf4770dd44920543704ed5fed5ee308221dd89

commit eecf4770dd44920543704ed5fed5ee308221dd89
Author: Alexandre Courbot <acourbot@chromium.org>
Date: Wed Sep 20 06:58:39 2017

Revert "libva: disable info messages"

This reverts commit 066fe0750656c2f407ec42045038ce8e71ad6af8.

Using --disable-va-messaging disables both info and error messages. We
still want to get the later, so we will use the LIBVA_MESSAGING_LEVEL
environment variable to control this instead.

BUG= chromium:752187 
CQ-DEPEND=CL:646992
TEST=checked that libva errors were reporting, but not info-level
messages.

Change-Id: I3b0ca428ab3e4145bd9d00d8c8c2118385e90c4a
Reviewed-on: https://chromium-review.googlesource.com/646399
Commit-Ready: Alexandre Courbot <acourbot@chromium.org>
Tested-by: Alexandre Courbot <acourbot@chromium.org>
Reviewed-by: Pawel Osciak <posciak@chromium.org>

[modify] https://crrev.com/eecf4770dd44920543704ed5fed5ee308221dd89/x11-libs/libva/libva-1.8.3.ebuild
[rename] https://crrev.com/eecf4770dd44920543704ed5fed5ee308221dd89/x11-libs/libva/libva-1.8.3-r3.ebuild