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fe598ab37e
The macro FAN_FROM_REG evaluates its arguments multiple times. When used with shared driver data, this leads to Time-of-Check to Time-of-Use (TOCTOU) race conditions, potentially causing divide-by-zero errors. Convert the macro to a static function to ensure arguments are evaluated only once. Additionally, in fan_div_store, move the reading of the old register value and the calculation of the minimum limit inside the update lock. This ensures that the read-modify-write sequence operates on consistent data, preventing race conditions during fan divider updates. Link: https://lore.kernel.org/all/CALbr=LYJ_ehtp53HXEVkSpYoub+XYSTU8Rg=o1xxMJ8=5z8B-g@mail.gmail.com/ Signed-off-by: Gui-Dong Han <hanguidong02@gmail.com> Link: https://lore.kernel.org/r/20251124165900.4713-1-hanguidong02@gmail.com [groeck: Dropped unnecessary line split] Signed-off-by: Guenter Roeck <linux@roeck-us.net>
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 reStructuredText 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.