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fed71f7d98
Rick bisected a regression on large systems which use the x2apic cluster
mode for interrupt delivery to the commit wich reworked the cluster
management.
The problem is caused by a missing initialization of the clusterid field
in the shared cluster data structures. So all structures end up with
cluster ID 0 which only allows sharing between all CPUs which belong to
cluster 0. All other CPUs with a cluster ID > 0 cannot share the data
structure because they cannot find existing data with their cluster
ID. This causes malfunction with IPIs because IPIs are sent to the wrong
cluster and the caller waits for ever that the target CPU handles the IPI.
Add the missing initialization when a upcoming CPU is the first in a
cluster so that the later booting CPUs can find the data and share it for
proper operation.
Fixes: 023a611748 ("x86/apic/x2apic: Simplify cluster management")
Reported-by: Rick Warner <rick@microway.com>
Bisected-by: Rick Warner <rick@microway.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Rick Warner <rick@microway.com>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/alpine.DEB.2.21.1805171418210.1947@nanos.tec.linutronix.de
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.