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.
Sebastian Andrzej Siewior
authored
There was a lockdep which led to commit fad003b6 ("Bluetooth: Fix inconsistent lock state with RFCOMM") Lockdep noticed that `sk->sk_lock.slock' was acquired without disabling the softirq while the lock was also used in softirq context. Unfortunately the solution back then was to disable interrupts before acquiring the lock which however made lockdep happy. It would have been enough to simply disable the softirq. Disabling interrupts before acquiring a spinlock_t is not allowed on PREEMPT_RT because these locks are converted to 'sleeping' spinlocks. Use spin_lock_bh() in order to acquire the `sk_lock.slock'. Reported-by:Luis Claudio R. Goncalves <lclaudio@uudg.org> Reported-by: kbuild test robot <lkp@intel.com> [missing unlock] Signed-off-by:
Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by:
Marcel Holtmann <marcel@holtmann.org>