Commit 837c4ef1 authored by Yinghai Lu's avatar Yinghai Lu Committed by Jesse Barnes
Browse files

PCI: clear bridge resource range if BIOS assigned bad one 

Yannick found that video does not work with 2.6.34.  The cause of this
bug was that the BIOS had assigned the wrong range to the PCI bridge
above the video device.  Before 2.6.34 the kernel would have shrunk
the size of the bridge window, but since
  d65245c3 PCI: don't shrink bridge resources
the kernel will avoid shrinking BIOS ranges.

So zero out the old range if we fail to claim it at boot time; this will
cause us to allocate a new range at startup, restoring the 2.6.34
behavior.

Fixes regression https://bugzilla.kernel.org/show_bug.cgi?id=16009

.

Reported-by: default avatarYannick <yannick.roehlly@free.fr>
Acked-by: default avatarBjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: default avatarYinghai Lu <yinghai@kernel.org>
Signed-off-by: default avatarJesse Barnes <jbarnes@virtuousgeek.org>
parent a7ef7d1f

arch/microblaze/pci/pci-common.c

+1 −0
Original line number Diff line number Diff line
@@ -1277,6 +1277,7 @@ void pcibios_allocate_bus_resources(struct pci_bus *bus) 
		printk(KERN_WARNING "PCI: Cannot allocate resource region "

		       "%d of PCI bridge %d, will remap\n", i, bus->number);

clear_resource:

		res->start = res->end = 0;

		res->flags = 0;

	}

arch/mn10300/unit-asb2305/pci-asb2305.c

+1 −0
Original line number Diff line number Diff line
@@ -117,6 +117,7 @@ static void __init pcibios_allocate_bus_resources(struct list_head *bus_list) 
					 * Invalidate the resource to prevent

					 * child resource allocations in this

					 * range. */

					r->start = r->end = 0;

					r->flags = 0;

				}

			}

arch/powerpc/kernel/pci-common.c

+1 −0
Original line number Diff line number Diff line
@@ -1309,6 +1309,7 @@ void pcibios_allocate_bus_resources(struct pci_bus *bus) 
		printk(KERN_WARNING "PCI: Cannot allocate resource region "

		       "%d of PCI bridge %d, will remap\n", i, bus->number);

clear_resource:

		res->start = res->end = 0;

		res->flags = 0;

	}

arch/x86/pci/i386.c

+2 −0
Original line number Diff line number Diff line
@@ -96,6 +96,7 @@ EXPORT_SYMBOL(pcibios_align_resource); 
 *	  the fact the PCI specs explicitly allow address decoders to be

 *	  shared between expansion ROMs and other resource regions, it's

 *	  at least dangerous)

 *	- bad resource sizes or overlaps with other regions

 *

 *  Our solution:

 *	(1) Allocate resources for all buses behind PCI-to-PCI bridges.
@@ -136,6 +137,7 @@ static void __init pcibios_allocate_bus_resources(struct list_head *bus_list) 
					 * child resource allocations in this

					 * range.

					 */

					r->start = r->end = 0;

					r->flags = 0;

				}

			}

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