Clarify why relaxed hardware domains don't need iommu page-table
syncing.
Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
---
Cc: Jan Beulich <jbeulich@suse.com>
---
xen/drivers/passthrough/iommu.c | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/xen/drivers/passthrough/iommu.c b/xen/drivers/passthrough/iommu.c
index 79ec6719f5..f8c3bf53bd 100644
--- a/xen/drivers/passthrough/iommu.c
+++ b/xen/drivers/passthrough/iommu.c
@@ -185,6 +185,10 @@ void __hwdom_init iommu_hwdom_init(struct domain *d)
register_keyhandler('o', &iommu_dump_p2m_table, "dump iommu p2m table", 0);
hd->status = IOMMU_STATUS_initializing;
+ /*
+ * NB: relaxed hw domains don't need sync because all ram is already
+ * mapped in the iommu page tables.
+ */
hd->need_sync = iommu_hwdom_strict && !iommu_use_hap_pt(d);
if ( need_iommu_pt_sync(d) )
{
--
2.20.1 (Apple Git-117)
_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xenproject.org
https://lists.xenproject.org/mailman/listinfo/xen-devel