]> git.karo-electronics.de Git - linux-beck.git/commit
PCI: Disable IO/MEM decoding for devices with non-compliant BARs
authorBjorn Helgaas <bhelgaas@google.com>
Thu, 25 Feb 2016 20:35:57 +0000 (14:35 -0600)
committerBjorn Helgaas <bhelgaas@google.com>
Thu, 25 Feb 2016 20:35:57 +0000 (14:35 -0600)
commitb84106b4e2290c081cdab521fa832596cdfea246
treea7c5625264ef1ba58fe939c95aef40a12590a78e
parent92e963f50fc74041b5e9e744c330dca48e04f08d
PCI: Disable IO/MEM decoding for devices with non-compliant BARs

The PCI config header (first 64 bytes of each device's config space) is
defined by the PCI spec so generic software can identify the device and
manage its usage of I/O, memory, and IRQ resources.

Some non-spec-compliant devices put registers other than BARs where the
BARs should be.  When the PCI core sizes these "BARs", the reads and writes
it does may have unwanted side effects, and the "BAR" may appear to
describe non-sensical address space.

Add a flag bit to mark non-compliant devices so we don't touch their BARs.
Turn off IO/MEM decoding to prevent the devices from consuming address
space, since we can't read the BARs to find out what that address space
would be.

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Tested-by: Andi Kleen <ak@linux.intel.com>
CC: stable@vger.kernel.org
drivers/pci/probe.c
include/linux/pci.h