Linux mainline fork with MSM8998 patches | https://mainline.space | Currently supported devices:
OnePlus 5/5T, Xiaomi Mi 6, F(x)tec Pro¹ (2019 QX1000 model) & Sony Xperia XZ Premium (UNTESTED!)
56d1c14ecf
While this isn't a complete fix, this will improve the reliability of drm_dp_get_last_connected_port_and_mstb() pretty significantly during hotplug events, since there's a chance that the in-memory topology tree may not be fully updated when drm_dp_get_last_connected_port_and_mstb() is called and thus might end up causing our search to fail on an mstb whose topology refcount has reached 0, but has not yet been removed from it's parent. Ideally, we should further fix this problem by ensuring that we deal with the potential for racing with a hotplug event, which would look like this: * drm_dp_payload_send_msg() retrieves the last living relative of mstb with drm_dp_get_last_connected_port_and_mstb() * drm_dp_payload_send_msg() starts building payload message At the same time, mstb gets unplugged from the topology and is no longer the actual last living relative of the original mstb * drm_dp_payload_send_msg() tries sending the payload message, hub times out * Hub timed out, we give up and run away-resulting in the payload being leaked This could be fixed by restarting the drm_dp_get_last_connected_port_and_mstb() search whenever we get a timeout, sending the payload to the new mstb, then repeating until either the entire topology is removed from the system or drm_dp_get_last_connected_port_and_mstb() fails. But since the above race condition is not terribly likely, we'll address that in a later patch series once we've improved the recovery handling for VCPI allocations in the rest of the DP MST helpers. Changes since v1: * Convert kerneldoc for drm_dp_get_last_connected_port_and_mstb to normal comment - danvet Signed-off-by: Lyude Paul <lyude@redhat.com> Reviewed-by: Harry Wentland <harry.wentland@amd.com> Reviewed-by: Daniel Vetter <daniel@ffwll.ch> Cc: David Airlie <airlied@redhat.com> Cc: Jerry Zuo <Jerry.Zuo@amd.com> Cc: Juston Li <juston.li@intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20190111005343.17443-8-lyude@redhat.com |
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| drivers | ||
| firmware | ||
| fs | ||
| include | ||
| init | ||
| ipc | ||
| kernel | ||
| lib | ||
| LICENSES | ||
| mm | ||
| net | ||
| samples | ||
| scripts | ||
| security | ||
| sound | ||
| tools | ||
| usr | ||
| virt | ||
| .clang-format | ||
| .cocciconfig | ||
| .get_maintainer.ignore | ||
| .gitattributes | ||
| .gitignore | ||
| .mailmap | ||
| COPYING | ||
| CREDITS | ||
| Kbuild | ||
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| MAINTAINERS | ||
| Makefile | ||
| 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.