intel-iommu: Cope with yet another BIOS screwup causing crashes

Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

1 files changed, 11 insertions, 0 deletions

diff --git a/drivers/pci/intel-iommu.c b/drivers/pci/intel-iommu.c
index beb5ccfd89bd..d36fa80aaa52 100644
--- a/drivers/pci/intel-iommu.c
+++ b/drivers/pci/intel-iommu.c
@@ -1974,6 +1974,17 @@ static int iommu_prepare_identity_map(struct pci_dev *pdev,
         printk(KERN_INFO
                "IOMMU: Setting identity map for device %s [0x%Lx - 0x%Lx]\n",
                pci_name(pdev), start, end);
+        
+        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",
+                     agaw_to_width(domain->agaw),
+                     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;
+        }
 
         ret = iommu_domain_identity_map(domain, start, end);
         if (ret)