[tip:x86/urgent] x86/pci: Intel ioh bus num reg accessing fix

[tip-bot for Yinghai Lu <yinghai@kernel.org>]

Commit-ID:  a557aae29cf5916295c234d4b10ba3f8f29b8a96
Gitweb:     http://git.kernel.org/tip/a557aae29cf5916295c234d4b10ba3f8f29b8a96
Author:     Yinghai Lu <yinghai@kernel.org>
AuthorDate: Tue, 22 Dec 2009 15:40:40 -0800
Committer:  H. Peter Anvin <hpa@zytor.com>
CommitDate: Mon, 4 Jan 2010 13:21:51 -0800

x86/pci: Intel ioh bus num reg accessing fix

It is above 0x100 (PCI-Express extended register space), so if mmconf
is not enable, we can't access it.

[ hpa: changed the bound from 0x200 to 0x120, which is the tight
  bound. ]

Reported-by: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
LKML-Reference: <1261525263-13763-3-git-send-email-yinghai@kernel.org>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
---
 arch/x86/pci/intel_bus.c |    4 ++++
 1 files changed, 4 insertions(+), 0 deletions(-)

diff --git a/arch/x86/pci/intel_bus.c b/arch/x86/pci/intel_bus.c
index b7a55dc..f81a2fa 100644
--- a/arch/x86/pci/intel_bus.c
+++ b/arch/x86/pci/intel_bus.c
@@ -49,6 +49,10 @@ static void __devinit pci_root_bus_res(struct pci_dev *dev)
 	u64 mmioh_base, mmioh_end;
 	int bus_base, bus_end;
 
+	/* some sys doesn't get mmconf enabled */
+	if (dev->cfg_size < 0x120)
+		return;
+
 	if (pci_root_num >= PCI_ROOT_NR) {
 		printk(KERN_DEBUG "intel_bus.c: PCI_ROOT_NR is too small\n");
 		return;