599cf4b845
From: Marc Zyngier <maz@kernel.org> commit d802057c7c553ad426520a053da9f9fe08e2c35a upstream. [ This commit is almost a rewrite because it conflicts with Thomas Gleixner's refactoring of this code in v5.17-rc1. I wasn't sure if I should drop all the s-o-bs (including Mark's), but decided to keep as the original commit ] When booting with maxcpus=<small number>, interrupt controllers such as the GICv3 ITS may not be able to satisfy the affinity of some managed interrupts, as some of the HW resources are simply not available. The same thing happens when loading a driver using managed interrupts while CPUs are offline. In order to deal with this, do not try to activate such interrupt if there is no online CPU capable of handling it. Instead, place it in shutdown state. Once a capable CPU shows up, it will be activated. Reported-by: John Garry <john.garry@huawei.com> Reported-by: David Decotigny <ddecotig@google.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: John Garry <john.garry@huawei.com> Link: https://lore.kernel.org/r/20220405185040.206297-2-maz@kernel.org Signed-off-by: Luiz Capitulino <luizcap@amazon.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.