9851ad2f71
commit ec7099fdea8025988710ee6fecfd4e4210c29ab5 upstream.
This reverts commit 3d5bfbd9716318b1ca5c38488aa69f64d38a9aa5.
When booting with threadirqs, it causes a splat
WARNING: CPU: 0 PID: 29 at kernel/irq/handle.c:159 __handle_irq_event_percpu+0x1ec/0x27c
irq 66 handler irq_default_primary_handler+0x0/0x1c enabled interrupts
That splat later went away with commit 81e2073c175b ("genirq: Disable
interrupts for force threaded handlers"), which got backported to
-stable. However, when running an -rt kernel, the splat still
exists. Moreover, quoting Thomas Gleixner [1]
But 3d5bfbd97163 ("gpio: mpc8xxx: change the gpio interrupt flags.")
has nothing to do with that:
"Delete the interrupt IRQF_NO_THREAD flags in order to gpio interrupts
can be threaded to allow high-priority processes to preempt."
This changelog is blatantly wrong. In mainline forced irq threads
have always been invoked with softirqs disabled, which obviously
makes them non-preemptible.
So the patch didn't even do what its commit log said.
[1] https://lore.kernel.org/lkml/871r8zey88.ffs@nanos.tec.linutronix.de/
Cc: stable@vger.kernel.org # v5.9+
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.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.