diff --git a/drivers/iommu/dmar.c b/drivers/iommu/dmar.c index a7967ceb79e6..785675a56a10 100644 --- a/drivers/iommu/dmar.c +++ b/drivers/iommu/dmar.c @@ -309,6 +309,7 @@ parse_dmar_table(void) struct acpi_table_dmar *dmar; struct acpi_dmar_header *entry_header; int ret = 0; + int drhd_count = 0; /* * Do it again, earlier dmar_tbl mapping could be mapped with @@ -347,6 +348,7 @@ parse_dmar_table(void) switch (entry_header->type) { case ACPI_DMAR_TYPE_HARDWARE_UNIT: + drhd_count++; ret = dmar_parse_one_drhd(entry_header); break; case ACPI_DMAR_TYPE_RESERVED_MEMORY: @@ -371,6 +373,8 @@ parse_dmar_table(void) entry_header = ((void *)entry_header + entry_header->length); } + if (drhd_count == 0) + pr_warn(FW_BUG "No DRHD structure found in DMAR table\n"); return ret; }