iommu/amd: Allow NULL pointer parameter for domain_flush_complete()

If domain == NULL is passed to the function, it will queue a
completion-wait command on all IOMMUs in the system.

Signed-off-by: Joerg Roedel <jroedel@suse.de>

1 files changed, 1 insertions, 1 deletions

diff --git a/drivers/iommu/amd_iommu.c b/drivers/iommu/amd_iommu.c
index 38f8a5e461fc..0884b126d932 100644
--- a/drivers/iommu/amd_iommu.c
+++ b/drivers/iommu/amd_iommu.c
@@ -1177,7 +1177,7 @@ static void domain_flush_complete(struct protection_domain *domain)
         int i;
 
         for (i = 0; i < amd_iommus_present; ++i) {
-                if (!domain->dev_iommu[i])
+                if (domain && !domain->dev_iommu[i])
                         continue;
 
                 /*