c180d65df8
[ Upstream commit e8d1b41e69d72c62865bebe8f441163ec00b3d44 ] With the to-be-fixed commit, the reset_work handler cleared 'host->mrq' outside of the spinlock protected critical section. That leaves a small race window during execution of 'tmio_mmc_reset()' where the done_work handler could grab a pointer to the now invalid 'host->mrq'. Both would use it to call mmc_request_done() causing problems (see link below). However, 'host->mrq' cannot simply be cleared earlier inside the critical section. That would allow new mrqs to come in asynchronously while the actual reset of the controller still needs to be done. So, like 'tmio_mmc_set_ios()', an ERR_PTR is used to prevent new mrqs from coming in but still avoiding concurrency between work handlers. Reported-by: Dirk Behme <dirk.behme@de.bosch.com> Closes: https://lore.kernel.org/all/20240220061356.3001761-1-dirk.behme@de.bosch.com/ Fixes: df3ef2d3c92c ("mmc: protect the tmio_mmc driver against a theoretical race") Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Tested-by: Dirk Behme <dirk.behme@de.bosch.com> Reviewed-by: Dirk Behme <dirk.behme@de.bosch.com> Cc: stable@vger.kernel.org # 3.0+ Link: https://lore.kernel.org/r/20240305104423.3177-2-wsa+renesas@sang-engineering.com Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
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.