]> git.kernelconcepts.de Git - karo-tx-linux.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)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Tue, 12 Apr 2016 16:08:37 +0000 (09:08 -0700)
commit8cbac3c4f74d92bf04645a613e061ab4f9baa866
treec3a69f0e012bac7c95e9ab618a5b5da6644fa7a6
parent88c9954c5c898dfe2e581cba34417ab5abccdd0d
PCI: Disable IO/MEM decoding for devices with non-compliant BARs

commit b84106b4e2290c081cdab521fa832596cdfea246 upstream.

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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/pci/probe.c
include/linux/pci.h