4ac3b0f14a
commit d8558ac8c93d429d65d7490b512a3a67e559d0d4 upstream.
According to documentation [0] the correct offset for the Upstream Peer
Decode Configuration Register (UPDCR) is 0x1014. It was previously defined
as 0x1114.
d99321b63b1f ("PCI: Enable quirks for PCIe ACS on Intel PCH root ports")
intended to enforce isolation between PCI devices allowing them to be put
into separate IOMMU groups. Due to the wrong register offset the intended
isolation was not fully enforced. This is fixed with this patch.
Please note that I did not test this patch because I have no hardware that
implements this register.
[0] https://www.intel.com/content/dam/www/public/us/en/documents/datasheets/4th-gen-core-family-mobile-i-o-datasheet.pdf (page 325)
Fixes: d99321b63b1f ("PCI: Enable quirks for PCIe ACS on Intel PCH root ports")
Link: https://lore.kernel.org/r/7a3505df-79ba-8a28-464c-88b83eefffa6@kernkonzept.com
Signed-off-by: Steffen Liebergeld <steffen.liebergeld@kernkonzept.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Andrew Murray <andrew.murray@arm.com>
Acked-by: Ashok Raj <ashok.raj@intel.com>
Cc: stable@vger.kernel.org # v3.15+
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Linux kernel ============ This file was moved to Documentation/admin-guide/README.rst Please notice that there are several guides for kernel developers and users. These guides can be rendered in a number of formats, like HTML and PDF. In order to build the documentation, use ``make htmldocs`` or ``make pdfdocs``. 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.