[PATCH -stable] amd_iommu: attach device fails on the last pci device

[Shuah Khan <shuah.khan-VXdhtT5mjnY@public.gmane.org>]

amd_iommu_attach_device() checks if device id is within the limits
of amd_iommu_last_bdf and instead checking if devid > amd_iommu_last_bdf,
it checks devid >= amd_iommu_last_bdf. As a result the last device attach
fails because amd_iommu_attach_device() returns an -EINVAL.

This bug is in linux-2.6.32 and an equivalent fix in linux-2.6.33 and has been
carried forward to later kernels and is in the upstream kernel. This equivalent
fix includes restructuring and consolidating device checks into a routine
check_device(). Instead of back-porting all of that work, spot-fixed the bug in
amd_iommu_attach_device() for linux-2.6.32.

Signed-off-by: Shuah Khan <shuah.khan-VXdhtT5mjnY@public.gmane.org>
CC: <stable-u79uwXL29TY76Z2rM5mHXA@public.gmane.org> v2.6.32
---
 arch/x86/kernel/amd_iommu.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/kernel/amd_iommu.c b/arch/x86/kernel/amd_iommu.c
index 3a44b75..67de7d7 100644
--- a/arch/x86/kernel/amd_iommu.c
+++ b/arch/x86/kernel/amd_iommu.c
@@ -2288,7 +2288,7 @@ static int amd_iommu_attach_device(struct iommu_domain *dom,
 
 	devid = calc_devid(pdev->bus->number, pdev->devfn);
 
-	if (devid >= amd_iommu_last_bdf ||
+	if (devid > amd_iommu_last_bdf ||
 			devid != amd_iommu_alias_table[devid])
 		return -EINVAL;
 
-- 
1.7.9.5