[146/151] intel-iommu: Check for an RMRR which ends before it starts.

Greg KH
2009-12-17T04:06:15Z

From: David Woodhouse <David.Woodhouse@intel.com>

commit 5595b528b49a702c0428c0762bab60999648254c upstream.

Some HP BIOSes report an RMRR region (a region which needs a 1:1 mapping
in the IOMMU for a given device) which has an end address lower than its
start address. Detect that and warn, rather than triggering the
BUG() in dma_pte_clear_range().

Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

---
drivers/pci/intel-iommu.c | 10 ++++++++++
1 file changed, 10 insertions(+)

--- a/drivers/pci/intel-iommu.c
+++ b/drivers/pci/intel-iommu.c
@@ -1991,6 +1991,16 @@ static int iommu_prepare_identity_map(st
"IOMMU: Setting identity map for device %s [0x%Lx - 0x%Lx]\n",
pci_name(pdev), start, end);

+ if (end < start) {
+ WARN(1, "Your BIOS is broken; RMRR ends before it starts!\n"
+ "BIOS vendor: %s; Ver: %s; Product Version: %s\n",
+ dmi_get_system_info(DMI_BIOS_VENDOR),
+ dmi_get_system_info(DMI_BIOS_VERSION),
+ dmi_get_system_info(DMI_PRODUCT_VERSION));
+ ret = -EIO;
+ goto error;
+ }
+
if (end >> agaw_to_width(domain->agaw)) {
WARN(1, "Your BIOS is broken; RMRR exceeds permitted address width (%d bits)\n"
"BIOS vendor: %s; Ver: %s; Product Version: %s\n",