From 837c4ef13c44296bb763a0ca0e84a076592474cf Mon Sep 17 00:00:00 2001 From: Yinghai Lu <yinghai.lu@oracle.com> Date: Thu, 3 Jun 2010 13:43:03 -0700 Subject: [PATCH] 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 <yannick.roehlly@free.fr> Acked-by: Bjorn Helgaas <bjorn.helgaas@hp.com> Signed-off-by: Yinghai Lu <yinghai@kernel.org> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org> --- arch/microblaze/pci/pci-common.c | 1 + arch/mn10300/unit-asb2305/pci-asb2305.c | 1 + arch/powerpc/kernel/pci-common.c | 1 + arch/x86/pci/i386.c | 2 ++ 4 files changed, 5 insertions(+) diff --git a/arch/microblaze/pci/pci-common.c b/arch/microblaze/pci/pci-common.c index 9cb782b8e036f..23be25fec4d67 100644 --- a/arch/microblaze/pci/pci-common.c +++ b/arch/microblaze/pci/pci-common.c @@ -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; } diff --git a/arch/mn10300/unit-asb2305/pci-asb2305.c b/arch/mn10300/unit-asb2305/pci-asb2305.c index d6119b879a981..45b40ac6c4647 100644 --- a/arch/mn10300/unit-asb2305/pci-asb2305.c +++ b/arch/mn10300/unit-asb2305/pci-asb2305.c @@ -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; } } diff --git a/arch/powerpc/kernel/pci-common.c b/arch/powerpc/kernel/pci-common.c index 6646005dffb10..5b38f6ae2b299 100644 --- a/arch/powerpc/kernel/pci-common.c +++ b/arch/powerpc/kernel/pci-common.c @@ -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; } diff --git a/arch/x86/pci/i386.c b/arch/x86/pci/i386.c index 97da2ba9344b4..6fdb3ec30c319 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; } } -- GitLab