[PATCH 4.0-testing 10/10] AMD, IOMMU: Make per-device interrupt remapping table default

[Ian Campbell <ian.campbell@citrix.com>]

From: Boris Ostrovsky <boris.ostrovsky@amd.com>

Using global interrupt remapping table may be insecure, as
described by XSA-36. This patch makes per-device mode default.

This is XSA-36 / CVE-2013-0153.

Signed-off-by: Boris Ostrovsky <boris.ostrovsky@amd.com>

Moved warning in amd_iov_detect() to location covering all cases.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
xen-unstable changeset: 26519:1af531e7bc2f
xen-unstable date: Tue Feb  5 14:22:11 UTC 2013
---
 xen/drivers/passthrough/amd/iommu_acpi.c    |    5 +++--
 xen/drivers/passthrough/amd/pci_amd_iommu.c |    2 ++
 xen/drivers/passthrough/iommu.c             |    4 +++-
 3 files changed, 8 insertions(+), 3 deletions(-)

diff --git a/xen/drivers/passthrough/amd/iommu_acpi.c b/xen/drivers/passthrough/amd/iommu_acpi.c
index 0d6d2a6..bf4a691 100644
--- a/xen/drivers/passthrough/amd/iommu_acpi.c
+++ b/xen/drivers/passthrough/amd/iommu_acpi.c
@@ -20,7 +20,6 @@
 
 #include <xen/config.h>
 #include <xen/errno.h>
-#include <asm/apicdef.h>
 #include <asm/io_apic.h>
 #include <asm/amd-iommu.h>
 #include <asm/hvm/svm/amd-iommu-proto.h>
@@ -690,7 +689,7 @@ static u16 __init parse_ivhd_device_special(
             /* set device id of ioapic */
             ioapic_bdf[ivhd_device->special.handle].bdf = bdf;
 
-            ioapic_bdf[ivhd_device->special.handle].pin_setup = xzalloc_array(
+            ioapic_bdf[ivhd_device->special.handle].pin_setup = xmalloc_array(
                 unsigned long, BITS_TO_LONGS(nr_ioapic_registers[apic]));
             if ( nr_ioapic_registers[apic] &&
                  !ioapic_bdf[IO_APIC_ID(apic)].pin_setup )
@@ -698,6 +697,8 @@ static u16 __init parse_ivhd_device_special(
                 printk(XENLOG_ERR "IVHD Error: Out of memory\n");
                 return 0;
             }
+	    memset(ioapic_bdf[ivhd_device->special.handle].pin_setup, 0,
+		   sizeof(unsigned long) * BITS_TO_LONGS(nr_ioapic_registers[apic]));
         }
         return dev_length;
     }
diff --git a/xen/drivers/passthrough/amd/pci_amd_iommu.c b/xen/drivers/passthrough/amd/pci_amd_iommu.c
index fb29e20..597a06a 100644
--- a/xen/drivers/passthrough/amd/pci_amd_iommu.c
+++ b/xen/drivers/passthrough/amd/pci_amd_iommu.c
@@ -173,6 +173,8 @@ int amd_iov_detect(void)
         printk("Error initialization\n");
         return -ENODEV;
     }
+    if ( !amd_iommu_perdev_intremap )
+        printk(XENLOG_WARNING "AMD-Vi: Using global interrupt remap table is not recommended (see XSA-36)!\n");
     return 0;
 }
 
diff --git a/xen/drivers/passthrough/iommu.c b/xen/drivers/passthrough/iommu.c
index 0dad6ef..5b3c66b 100644
--- a/xen/drivers/passthrough/iommu.c
+++ b/xen/drivers/passthrough/iommu.c
@@ -48,7 +48,7 @@ bool_t __read_mostly iommu_snoop = 1;
 bool_t __read_mostly iommu_qinval = 1;
 bool_t __read_mostly iommu_intremap = 1;
 bool_t __read_mostly amd_iommu_debug;
-bool_t __read_mostly amd_iommu_perdev_intremap;
+bool_t __read_mostly amd_iommu_perdev_intremap = 1;
 
 static void __init parse_iommu_param(char *s)
 {
@@ -78,6 +78,8 @@ static void __init parse_iommu_param(char *s)
             amd_iommu_debug = 1;
         else if ( !strcmp(s, "amd-iommu-perdev-intremap") )
             amd_iommu_perdev_intremap = 1;
+        else if ( !strcmp(s, "amd-iommu-global-intremap") )
+            amd_iommu_perdev_intremap = 0;
         else if ( !strcmp(s, "dom0-passthrough") )
             iommu_passthrough = 1;
         else if ( !strcmp(s, "dom0-strict") )
-- 
1.7.2.5