kmemcheck: add DMA hooks

This patch hooks into the DMA API to prevent the reporting of the false positives that would otherwise be reported when memory is accessed that is also used directly by devices. [rebased for mainline inclusion] Signed-off-by: Vegard Nossum <[email protected]>
rtvt123 · Jun 15, 2009 · d700285 · d700285
1 parent 2dff440
commit d700285
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diff --git a/arch/x86/include/asm/dma-mapping.h b/arch/x86/include/asm/dma-mapping.h
@@ -6,6 +6,7 @@
  * Documentation/DMA-API.txt for documentation.
  */
 
+#include <linux/kmemcheck.h>
 #include <linux/scatterlist.h>
 #include <linux/dma-debug.h>
 #include <linux/dma-attrs.h>
@@ -60,6 +61,7 @@ dma_map_single(struct device *hwdev, void *ptr, size_t size,
 	dma_addr_t addr;
 
 	BUG_ON(!valid_dma_direction(dir));
+	kmemcheck_mark_initialized(ptr, size);
 	addr = ops->map_page(hwdev, virt_to_page(ptr),
 			     (unsigned long)ptr & ~PAGE_MASK, size,
 			     dir, NULL);

diff --git a/include/linux/kmemcheck.h b/include/linux/kmemcheck.h
@@ -59,6 +59,22 @@ static inline bool kmemcheck_page_is_tracked(struct page *p)
 {
 	return false;
 }
+
+static inline void kmemcheck_mark_unallocated(void *address, unsigned int n)
+{
+}
+
+static inline void kmemcheck_mark_uninitialized(void *address, unsigned int n)
+{
+}
+
+static inline void kmemcheck_mark_initialized(void *address, unsigned int n)
+{
+}
+
+static inline void kmemcheck_mark_freed(void *address, unsigned int n)
+{
+}
 #endif /* CONFIG_KMEMCHECK */
 
 #endif /* LINUX_KMEMCHECK_H */