1 files changed, 28 insertions, 15 deletions

diff --git a/lib/dma-debug.c b/lib/dma-debug.c
index add80cc02dbe..9722bd2dbc9b 100644
--- a/lib/dma-debug.c
+++ b/lib/dma-debug.c
@@ -102,6 +102,14 @@ static DEFINE_SPINLOCK(free_entries_lock);
 /* Global disable flag - will be set in case of an error */
 static u32 global_disable __read_mostly;
 
+/* Early initialization disable flag, set at the end of dma_debug_init */
+static bool dma_debug_initialized __read_mostly;
+
+static inline bool dma_debug_disabled(void)
+{
+        return global_disable || !dma_debug_initialized;
+}
+
 /* Global error count */
 static u32 error_count;
 
@@ -945,7 +953,7 @@ static int dma_debug_device_change(struct notifier_block *nb, unsigned long acti
         struct dma_debug_entry *uninitialized_var(entry);
         int count;
 
-        if (global_disable)
+        if (dma_debug_disabled())
                 return 0;
 
         switch (action) {
@@ -973,7 +981,7 @@ void dma_debug_add_bus(struct bus_type *bus)
 {
         struct notifier_block *nb;
 
-        if (global_disable)
+        if (dma_debug_disabled())
                 return;
 
         nb = kzalloc(sizeof(struct notifier_block), GFP_KERNEL);
@@ -994,6 +1002,9 @@ void dma_debug_init(u32 num_entries)
 {
         int i;
 
+        /* Do not use dma_debug_initialized here, since we really want to be
+         * called to set dma_debug_initialized
+         */
         if (global_disable)
                 return;
 
@@ -1021,6 +1032,8 @@ void dma_debug_init(u32 num_entries)
 
         nr_total_entries = num_free_entries;
 
+        dma_debug_initialized = true;
+
         pr_info("DMA-API: debugging enabled by kernel config\n");
 }
 
@@ -1243,7 +1256,7 @@ void debug_dma_map_page(struct device *dev, struct page *page, size_t offset,
 {
         struct dma_debug_entry *entry;
 
-        if (unlikely(global_disable))
+        if (unlikely(dma_debug_disabled()))
                 return;
 
         if (dma_mapping_error(dev, dma_addr))
@@ -1283,7 +1296,7 @@ void debug_dma_mapping_error(struct device *dev, dma_addr_t dma_addr)
         struct hash_bucket *bucket;
         unsigned long flags;
 
-        if (unlikely(global_disable))
+        if (unlikely(dma_debug_disabled()))
                 return;
 
         ref.dev = dev;
@@ -1325,7 +1338,7 @@ void debug_dma_unmap_page(struct device *dev, dma_addr_t addr,
                 .direction      = direction,
         };
 
-        if (unlikely(global_disable))
+        if (unlikely(dma_debug_disabled()))
                 return;
 
         if (map_single)
@@ -1342,7 +1355,7 @@ void debug_dma_map_sg(struct device *dev, struct scatterlist *sg,
         struct scatterlist *s;
         int i;
 
-        if (unlikely(global_disable))
+        if (unlikely(dma_debug_disabled()))
                 return;
 
         for_each_sg(sg, s, mapped_ents, i) {
@@ -1395,7 +1408,7 @@ void debug_dma_unmap_sg(struct device *dev, struct scatterlist *sglist,
         struct scatterlist *s;
         int mapped_ents = 0, i;
 
-        if (unlikely(global_disable))
+        if (unlikely(dma_debug_disabled()))
                 return;
 
         for_each_sg(sglist, s, nelems, i) {
@@ -1427,7 +1440,7 @@ void debug_dma_alloc_coherent(struct device *dev, size_t size,
 {
         struct dma_debug_entry *entry;
 
-        if (unlikely(global_disable))
+        if (unlikely(dma_debug_disabled()))
                 return;
 
         if (unlikely(virt == NULL))
@@ -1462,7 +1475,7 @@ void debug_dma_free_coherent(struct device *dev, size_t size,
                 .direction      = DMA_BIDIRECTIONAL,
         };
 
-        if (unlikely(global_disable))
+        if (unlikely(dma_debug_disabled()))
                 return;
 
         check_unmap(&ref);
@@ -1474,7 +1487,7 @@ void debug_dma_sync_single_for_cpu(struct device *dev, dma_addr_t dma_handle,
 {
         struct dma_debug_entry ref;
 
-        if (unlikely(global_disable))
+        if (unlikely(dma_debug_disabled()))
                 return;
 
         ref.type         = dma_debug_single;
@@ -1494,7 +1507,7 @@ void debug_dma_sync_single_for_device(struct device *dev,
 {
         struct dma_debug_entry ref;
 
-        if (unlikely(global_disable))
+        if (unlikely(dma_debug_disabled()))
                 return;
 
         ref.type         = dma_debug_single;
@@ -1515,7 +1528,7 @@ void debug_dma_sync_single_range_for_cpu(struct device *dev,
 {
         struct dma_debug_entry ref;
 
-        if (unlikely(global_disable))
+        if (unlikely(dma_debug_disabled()))
                 return;
 
         ref.type         = dma_debug_single;
@@ -1536,7 +1549,7 @@ void debug_dma_sync_single_range_for_device(struct device *dev,
 {
         struct dma_debug_entry ref;
 
-        if (unlikely(global_disable))
+        if (unlikely(dma_debug_disabled()))
                 return;
 
         ref.type         = dma_debug_single;
@@ -1556,7 +1569,7 @@ void debug_dma_sync_sg_for_cpu(struct device *dev, struct scatterlist *sg,
         struct scatterlist *s;
         int mapped_ents = 0, i;
 
-        if (unlikely(global_disable))
+        if (unlikely(dma_debug_disabled()))
                 return;
 
         for_each_sg(sg, s, nelems, i) {
@@ -1589,7 +1602,7 @@ void debug_dma_sync_sg_for_device(struct device *dev, struct scatterlist *sg,
         struct scatterlist *s;
         int mapped_ents = 0, i;
 
-        if (unlikely(global_disable))
+        if (unlikely(dma_debug_disabled()))
                 return;
 
         for_each_sg(sg, s, nelems, i) {