47078311b8
A problem about modprobe ingenic-drm failed is triggered with the following
log given:
[ 303.561088] Error: Driver 'ingenic-ipu' is already registered, aborting...
modprobe: ERROR: could not insert 'ingenic_drm': Device or resource busy
The reason is that ingenic_drm_init() returns platform_driver_register()
directly without checking its return value, if platform_driver_register()
failed, it returns without unregistering ingenic_ipu_driver_ptr, resulting
the ingenic-drm can never be installed later.
A simple call graph is shown as below:
ingenic_drm_init()
platform_driver_register() # ingenic_ipu_driver_ptr are registered
platform_driver_register()
driver_register()
bus_add_driver()
priv = kzalloc(...) # OOM happened
# return without unregister ingenic_ipu_driver_ptr
Fixing this problem by checking the return value of
platform_driver_register() and do platform_unregister_drivers() if
error happened.
Fixes: fc1acf317b01 ("drm/ingenic: Add support for the IPU")
Signed-off-by: Yuan Can <yuancan@huawei.com>
Cc: stable@vger.kernel.org
Signed-off-by: Paul Cercueil <paul@crapouillou.net>
Link: https://patchwork.freedesktop.org/patch/msgid/20221104064512.8569-1-yuancan@huawei.com
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.