From: Keir Fraser <keir.fraser@citrix.com>
Date: Mon, 19 Oct 2009 15:50:14 +0000 (+0100)
Subject: vtd: Disable VT-d if no DRHD units are probed.
X-Git-Tag: archive/raspbian/4.8.0-1+rpi1~1^2~13199
X-Git-Url: https://dgit.raspbian.org/%22http:/www.example.com/cgi/%22https:/%22bookmarks://%22/%22http:/www.example.com/cgi/%22https:/%22bookmarks:/%22?a=commitdiff_plain;h=6f8b0338a4df30f87865a42bdaec62b445fa762a;p=xen.git

vtd: Disable VT-d if no DRHD units are probed.

Signed-off-by: Keir Fraser <keir.fraser@citrix.com>
---

diff --git a/xen/drivers/passthrough/iommu.c b/xen/drivers/passthrough/iommu.c
index b1ce67f741..cfa74f9579 100644
--- a/xen/drivers/passthrough/iommu.c
+++ b/xen/drivers/passthrough/iommu.c
@@ -266,9 +266,11 @@ int iommu_setup(void)
 {
     int rc = -ENODEV;
 
-    rc = iommu_hardware_setup();
-
-    iommu_enabled = (rc == 0);
+    if ( iommu_enabled )
+    {
+        rc = iommu_hardware_setup();
+        iommu_enabled = (rc == 0);
+    }
 
     if ( force_iommu && !iommu_enabled )
         panic("IOMMU setup failed, crash Xen for security purpose!\n");
diff --git a/xen/drivers/passthrough/vtd/iommu.c b/xen/drivers/passthrough/vtd/iommu.c
index ddf1543fbc..4d5702e729 100644
--- a/xen/drivers/passthrough/vtd/iommu.c
+++ b/xen/drivers/passthrough/vtd/iommu.c
@@ -1707,7 +1707,7 @@ int intel_vtd_setup(void)
     struct acpi_drhd_unit *drhd;
     struct iommu *iommu;
 
-    if ( !iommu_enabled )
+    if ( list_empty(&acpi_drhd_units) )
         return -ENODEV;
 
     platform_quirks();
@@ -1760,18 +1760,15 @@ int intel_vtd_setup(void)
     P(iommu_intremap, "Interrupt Remapping");
 #undef P
 
+    /* Allocate domain id bitmap, and set bit 0 as reserved. */
     drhd = list_entry(acpi_drhd_units.next, typeof(*drhd), list);
-    if ( drhd != NULL )
-    {
-        /* Allocate domain id bitmap, and set bit 0 as reserved. */
-        domid_bitmap_size = cap_ndoms(drhd->iommu->cap);
-        domid_bitmap = xmalloc_array(unsigned long,
-                                     BITS_TO_LONGS(domid_bitmap_size));
-        if ( domid_bitmap == NULL )
-            goto error;
-        memset(domid_bitmap, 0, domid_bitmap_size / 8);
-        __set_bit(0, domid_bitmap);
-    }
+    domid_bitmap_size = cap_ndoms(drhd->iommu->cap);
+    domid_bitmap = xmalloc_array(unsigned long,
+                                 BITS_TO_LONGS(domid_bitmap_size));
+    if ( domid_bitmap == NULL )
+        goto error;
+    memset(domid_bitmap, 0, domid_bitmap_size / 8);
+    __set_bit(0, domid_bitmap);
 
     scan_pci_devices();