drm/amd/display: avoid using null object of framebuffer
Ma Ke authored
Instead of using state->fb->obj[0] directly, get object from framebuffer
by calling drm_gem_fb_get_obj() and return error code when object is
null to avoid using null object of framebuffer.

Fixes: 5d945cbc

 ("drm/amd/display: Create a file dedicated to planes")
Signed-off-by: default avatarMa Ke <make24@iscas.ac.cn>
Signed-off-by: default avatarAlex Deucher <alexander.deucher@amd.com>
(cherry picked from commit 73dd0ad9)
3b9a3323
Linux kernel
============

There are several guides for kernel developers and users. These guides can
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Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
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    https://www.kernel.org/doc/html/latest/

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

Please read the Documentation/process/changes.rst file, as it contains the
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the problems which may result by upgrading your kernel.