3d82475ad4
free_irq() waits until all handlers for this IRQ have completed. As the relevant handler (mv88e6xxx_g1_irq_thread_fn()) takes the chip's reg_lock it might never return if the thread calling free_irq() holds this lock. For the same reason kthread_cancel_delayed_work_sync() in the polling case must not hold this lock. Also first free the irq (or stop the worker respectively) such that mv88e6xxx_g1_irq_thread_work() isn't called any more before the irq mappings are dropped in mv88e6xxx_g1_irq_free_common() to prevent the worker thread to call handle_nested_irq(0) which results in a NULL-pointer exception. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: David S. Miller <davem@davemloft.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 Restructured Text markup notation.
See Documentation/00-INDEX for a list of what is contained in each file.
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.