Re: [PATCH 4.5 026/238] PCI: Disable IO/MEM decoding for devices with non-compliant BARs

From: Greg Kroah-Hartman
Date: Tue Apr 12 2016 - 10:32:20 EST


On Tue, Apr 12, 2016 at 12:45:13AM +0100, Ben Hutchings wrote:
> On Sun, 2016-04-10 at 11:33 -0700, Greg Kroah-Hartman wrote:
> > 4.5-stable review patch.  If anyone has any objections, please let me know.
> >
> > ------------------
> >
> > From: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>
> >
> > 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.
> [...]
>
> No objection, but patch 005/238 seems to depend on this so please
> reorder them so bisection will work.

Now reordered, thanks.

greg k-h