AMD,IOMMU: Make per-device interrupt remapping table default

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

--- a/xen/arch/x86/irq.c
+++ b/xen/arch/x86/irq.c
@@ -1614,9 +1614,6 @@
         d->arch.pirq_irq[pirq] = irq;
         d->arch.irq_pirq[irq] = pirq;
         spin_unlock_irqrestore(&desc->lock, flags);
-
-        if ( opt_irq_vector_map == OPT_IRQ_VECTOR_MAP_PERDEV )
-            printk(XENLOG_INFO "Per-device vector maps for GSIs not implemented yet.\n");
     }
 
 done:
--- a/xen/drivers/passthrough/amd/pci_amd_iommu.c
+++ b/xen/drivers/passthrough/amd/pci_amd_iommu.c
@@ -203,6 +203,8 @@
     {
         printk("AMD-Vi: Not overriding irq_vector_map setting\n");
     }
+    if ( !amd_iommu_perdev_intremap )
+        printk(XENLOG_WARNING "AMD-Vi: Using global interrupt remap table is not recommended (see XSA-36)!\n");
     return 0;
 }
 
--- a/xen/drivers/passthrough/iommu.c
+++ b/xen/drivers/passthrough/iommu.c
@@ -48,7 +48,7 @@
 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 @@
             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") )
