b837a9f5ab
The COEF access is done with two steps: setting the index then read or write the data. When multiple COEF accesses are performed concurrently, the index and data might be paired unexpectedly. In most cases, this isn't a big problem as the COEF setup is done at the initialization, but some dynamic changes like the mute LED may hit such a race. For avoiding the racy COEF accesses, this patch introduces a new mutex coef_mutex to alc_spec, and wrap the COEF accessing functions with it. Reported-by: Alexander Sergeyev <sergeev917@gmail.com> Cc: <stable@vger.kernel.org> Link: https://lore.kernel.org/r/20220111195229.a77wrpjclqwrx4bx@localhost.localdomain Link: https://lore.kernel.org/r/20220131075738.24323-1-tiwai@suse.de Signed-off-by: Takashi Iwai <tiwai@suse.de>
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.