From 2175710e8eee2db19c2653f4f748af15cbfcdcd7 Mon Sep 17 00:00:00 2001 From: Boris Ostrovsky Date: Tue, 5 Feb 2013 15:21:25 +0100 Subject: [PATCH] AMD,IOMMU: Disable IOMMU if SATA Combined mode is on AMD's SP5100 chipset can be placed into SATA Combined mode that may cause prevent dom0 from booting when IOMMU is enabled and per-device interrupt remapping table is used. While SP5100 erratum 28 requires BIOSes to disable this mode, some may still use it. This patch checks whether this mode is on and, if per-device table is in use, disables IOMMU. This is XSA-36 / CVE-2013-0153. Signed-off-by: Boris Ostrovsky Flipped operands of && in amd_iommu_init() to make the message issued by amd_sp5100_erratum28() match reality (when amd_iommu_perdev_intremap is zero, there's really no point in calling the function). Signed-off-by: Jan Beulich Committed-by: Jan Beulich --- xen/drivers/passthrough/amd/iommu_init.c | 33 ++++++++++++++++++++++++ 1 file changed, 33 insertions(+) diff --git a/xen/drivers/passthrough/amd/iommu_init.c b/xen/drivers/passthrough/amd/iommu_init.c index cdfdd2e832..780e2069c9 100644 --- a/xen/drivers/passthrough/amd/iommu_init.c +++ b/xen/drivers/passthrough/amd/iommu_init.c @@ -1120,12 +1120,45 @@ static int __init amd_iommu_setup_device_table( return 0; } +/* Check whether SP5100 SATA Combined mode is on */ +static bool_t __init amd_sp5100_erratum28(void) +{ + u32 bus, id; + u16 vendor_id, dev_id; + u8 byte; + + for (bus = 0; bus < 256; bus++) + { + id = pci_conf_read32(0, bus, 0x14, 0, PCI_VENDOR_ID); + + vendor_id = id & 0xffff; + dev_id = (id >> 16) & 0xffff; + + /* SP5100 SMBus module sets Combined mode on */ + if (vendor_id != 0x1002 || dev_id != 0x4385) + continue; + + byte = pci_conf_read8(0, bus, 0x14, 0, 0xad); + if ( (byte >> 3) & 1 ) + { + printk(XENLOG_WARNING "AMD-Vi: SP5100 erratum 28 detected, disabling IOMMU.\n" + "If possible, disable SATA Combined mode in BIOS or contact your vendor for BIOS update.\n"); + return 1; + } + } + + return 0; +} + int __init amd_iommu_init(void) { struct amd_iommu *iommu; BUG_ON( !iommu_found() ); + if ( amd_iommu_perdev_intremap && amd_sp5100_erratum28() ) + goto error_out; + ivrs_bdf_entries = amd_iommu_get_ivrs_dev_entries(); if ( !ivrs_bdf_entries ) -- 2.30.2