From: David Woodhouse Date: Wed, 2 Dec 2009 09:21:55 +0000 (+0000) Subject: intel-iommu: Check for an RMRR which ends before it starts. X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=5595b528b49a702c0428c0762bab60999648254c;p=linux-beck.git intel-iommu: Check for an RMRR which ends before it starts. 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(). Cc: stable@kernel.org Signed-off-by: David Woodhouse --- diff --git a/drivers/pci/intel-iommu.c b/drivers/pci/intel-iommu.c index cb5cae3e0205..83cabdc118db 100644 --- a/drivers/pci/intel-iommu.c +++ b/drivers/pci/intel-iommu.c @@ -2000,6 +2000,16 @@ static int iommu_prepare_identity_map(struct pci_dev *pdev, "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",