No description
  • C 98.2%
  • Assembly 1%
  • Makefile 0.3%
  • Shell 0.2%
  • Python 0.1%
Find a file
Repository files (latest commit first)
Filename Latest commit message Latest commit date
Hans Verkuil fe8b241e5e gpu: drm_dp_cec: fix broken CEC adapter properties check
[ Upstream commit 6daaae5ff7f3b23a2dacc9c387ff3d4f95b67cad ]

If the hotplug detect of a display is low for longer than one second
(configurable through drm_dp_cec_unregister_delay), then the CEC adapter
is unregistered since we assume the display was disconnected. If the
HPD went low for less than one second, then we check if the properties
of the CEC adapter have changed, since that indicates that we actually
switch to new hardware and we have to unregister the old CEC device and
register a new one.

Unfortunately, the test for changed properties was written poorly, and
after a new CEC capability was added to the CEC core code the test always
returned true (i.e. the properties had changed).

As a result the CEC device was unregistered and re-registered for every
HPD toggle. If the CEC remote controller integration was also enabled
(CONFIG_MEDIA_CEC_RC was set), then the corresponding input device was
also unregistered and re-registered. As a result the input device in
/sys would keep incrementing its number, e.g.:

/sys/devices/pci0000:00/0000:00:08.1/0000:e7:00.0/rc/rc0/input20

Since short HPD toggles are common, the number could over time get into
the thousands.

While not a serious issue (i.e. nothing crashes), it is not intended
to work that way.

This patch changes the test so that it only checks for the single CEC
capability that can actually change, and it ignores any other
capabilities, so this is now safe as well if new caps are added in
the future.

With the changed test the bit under #ifndef CONFIG_MEDIA_CEC_RC can be
dropped as well, so that's a nice cleanup.

Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Reported-by: Farblos <farblos@vodafonemail.de>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Fixes: 2c6d1fffa1 ("drm: add support for DisplayPort CEC-Tunneling-over-AUX")
Tested-by: Farblos <farblos@vodafonemail.de>
Link: https://patchwork.freedesktop.org/patch/msgid/361bb03d-1691-4e23-84da-0861ead5dbdc@xs4all.nl
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-03-13 12:43:05 +01:00
arch x86/mm: Don't disable PCID when INVLPG has been fixed by microcode 2025-03-13 12:43:03 +01:00
block partitions: ldm: remove the initial kernel-doc notation 2025-03-13 12:42:52 +01:00
certs certs/blacklist_hashes.c: fix const confusion in certs blacklist 2022-06-22 14:11:22 +02:00
crypto crypto: pcrypt - Call crypto layer directly when padata_do_parallel() return -EBUSY 2024-12-14 19:44:23 +01:00
Documentation dt-bindings: mmc: controller: clarify the address-cells description 2025-03-13 12:42:53 +01:00
drivers gpu: drm_dp_cec: fix broken CEC adapter properties check 2025-03-13 12:43:05 +01:00
fs nilfs2: handle errors that nilfs_prepare_chunk() may return 2025-03-13 12:43:04 +01:00
include usb: xhci: Add timeout argument in address_device USB HCD callback 2025-03-13 12:43:05 +01:00
init initramfs: avoid filename buffer overrun 2024-12-14 19:44:21 +01:00
ipc ipc: replace costly bailout check in sysvipc_find_ipc() 2024-09-04 13:15:02 +02:00
kernel tasklet: Introduce new initialization API 2025-03-13 12:43:04 +01:00
lib lib: string_helpers: silence snprintf() output truncation warning 2024-12-14 19:44:39 +01:00
LICENSES
mm mm: vmscan: account for free pages to prevent infinite Loop in throttle_direct_reclaim() 2025-01-09 13:23:37 +01:00
net sched: sch_cake: add bounds checks to host bulk flow fairness counts 2025-03-13 12:43:04 +01:00
samples samples/bpf: Fix a resource leak 2024-12-14 19:44:50 +01:00
scripts genksyms: fix memory leak when the same symbol is read from *.symref file 2025-03-13 12:43:00 +01:00
security tomoyo: don't emit warning in tomoyo_write_control() 2025-03-13 12:43:03 +01:00
sound ASoC: sun4i-spdif: Add clock multiplier settings 2025-03-13 12:42:55 +01:00
tools ktest.pl: Check kernelrelease return in get_version 2025-03-13 12:43:01 +01:00
usr
virt KVM: arm64: Ignore PMCNTENSET_EL0 while checking for overflow status 2024-12-19 18:05:04 +01:00
.clang-format
.cocciconfig
.get_maintainer.ignore
.gitattributes
.gitignore Remove *.orig pattern from .gitignore 2024-11-08 16:20:33 +01:00
.mailmap
COPYING
CREDITS
Kbuild
Kconfig
MAINTAINERS iio: stx104: Move to addac subdirectory 2023-08-30 16:27:12 +02:00
Makefile kbuild: userprogs: use correct lld when linking through clang 2025-03-13 12:43:04 +01:00
README

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.