From 837c4ef13c44296bb763a0ca0e84a076592474cf Mon Sep 17 00:00:00 2001 From: Yinghai Lu Date: Thu, 3 Jun 2010 13:43:03 -0700 Subject: 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 d65245c 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: Yannick Acked-by: Bjorn Helgaas Signed-off-by: Yinghai Lu Signed-off-by: Jesse Barnes --- arch/x86/pci/i386.c | 2 ++ 1 file changed, 2 insertions(+) (limited to 'arch/x86/pci/i386.c') diff --git a/arch/x86/pci/i386.c b/arch/x86/pci/i386.c index 97da2ba9344..6fdb3ec30c3 100644 --- a/arch/x86/pci/i386.c +++ b/arch/x86/pci/i386.c @@ -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; } } -- cgit v1.2.3-18-g5258