4bbd910de1
[ Upstream commit a6aca2f460e203781dc41391913cc5b54f4bc0ce ]
pdc_enable_intr() serves as a primitive to qcom_pdc_gic_{en,dis}able,
and has a raw spinlock for mutual exclusion, which is uses with
interruptible primitives.
This means that this critical section can itself be interrupted.
Should the interrupt also be a PDC interrupt, and the endpoint driver
perform an irq_disable() on that interrupt, we end-up in a deadlock.
Fix this by using the irqsave/irqrestore variants of the locking
primitives.
Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Maulik Shah <quic_mkshah@quicinc.com>
Link: https://lore.kernel.org/r/20220224101226.88373-5-maz@kernel.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.