6b4bcbf133
commit b9255a7cb51754e8d2645b65dd31805e282b4f3e upstream.
Nothing enforces the posted writes to be visible when the function
returns. Flush them even if the flush might be redundant when the entry is
masked already as the unmask will flush as well. This is either setup or a
rare affinity change event so the extra flush is not the end of the world.
While this is more a theoretical issue especially the logic in the X86
specific msi_set_affinity() function relies on the assumption that the
update has reached the hardware when the function returns.
Again, as this never has been enforced the Fixes tag refers to a commit in:
git://git.kernel.org/pub/scm/linux/kernel/git/tglx/history.git
Fixes: f036d4ea5fa7 ("[PATCH] ia32 Message Signalled Interrupt support")
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Marc Zyngier <maz@kernel.org>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20210729222542.515188147@linutronix.de
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.