1 files changed, 12 insertions, 2 deletions

diff --git a/drivers/acpi/arm64/iort.c b/drivers/acpi/arm64/iort.c
index d4eac6d7e9fb..2494138a6905 100644
--- a/drivers/acpi/arm64/iort.c
+++ b/drivers/acpi/arm64/iort.c
@@ -1107,6 +1107,11 @@ static int nc_dma_get_range(struct device *dev, u64 *size)
 
 	ncomp = (struct acpi_iort_named_component *)node->node_data;
 
+	if (!ncomp->memory_address_limit) {
+		pr_warn(FW_BUG "Named component missing memory address limit\n");
+		return -EINVAL;
+	}
+
 	*size = ncomp->memory_address_limit >= 64 ? U64_MAX :
 			1ULL<<ncomp->memory_address_limit;
 
@@ -1126,6 +1131,11 @@ static int rc_dma_get_range(struct device *dev, u64 *size)
 
 	rc = (struct acpi_iort_root_complex *)node->node_data;
 
+	if (!rc->memory_address_limit) {
+		pr_warn(FW_BUG "Root complex missing memory address limit\n");
+		return -EINVAL;
+	}
+
 	*size = rc->memory_address_limit >= 64 ? U64_MAX :
 			1ULL<<rc->memory_address_limit;
 
@@ -1173,8 +1183,8 @@ void iort_dma_setup(struct device *dev, u64 *dma_addr, u64 *dma_size)
 		end = dmaaddr + size - 1;
 		mask = DMA_BIT_MASK(ilog2(end) + 1);
 		dev->bus_dma_limit = end;
-		dev->coherent_dma_mask = mask;
-		*dev->dma_mask = mask;
+		dev->coherent_dma_mask = min(dev->coherent_dma_mask, mask);
+		*dev->dma_mask = min(*dev->dma_mask, mask);
 	}
 
 	*dma_addr = dmaaddr;