iommu/vt-d: fix wrong return value of dmar_table_init()
If dmar_table_init() fails to detect DMAR table on the first call,
it will return wrong result on following calls because it always
sets dmar_table_initialized no matter if succeeds or fails to
detect DMAR table.
Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Signed-off-by: Joerg Roedel <joro@8bytes.org>
diff --git a/drivers/iommu/dmar.c b/drivers/iommu/dmar.c
index 726cfe2..753c7ec 100644
--- a/drivers/iommu/dmar.c
+++ b/drivers/iommu/dmar.c
@@ -472,24 +472,23 @@
static int dmar_table_initialized;
int ret;
- if (dmar_table_initialized)
- return 0;
+ if (dmar_table_initialized == 0) {
+ ret = parse_dmar_table();
+ if (ret < 0) {
+ if (ret != -ENODEV)
+ pr_info("parse DMAR table failure.\n");
+ } else if (list_empty(&dmar_drhd_units)) {
+ pr_info("No DMAR devices found\n");
+ ret = -ENODEV;
+ }
- dmar_table_initialized = 1;
-
- ret = parse_dmar_table();
- if (ret) {
- if (ret != -ENODEV)
- pr_info("parse DMAR table failure.\n");
- return ret;
+ if (ret < 0)
+ dmar_table_initialized = ret;
+ else
+ dmar_table_initialized = 1;
}
- if (list_empty(&dmar_drhd_units)) {
- pr_info("No DMAR devices found\n");
- return -ENODEV;
- }
-
- return 0;
+ return dmar_table_initialized < 0 ? dmar_table_initialized : 0;
}
static void warn_invalid_dmar(u64 addr, const char *message)