[PATCH 3/4] maple_tree: Update internal warning and bug_on code

[Liam R. Howlett (Google)]

When CONFIG_DEBUG_MAPLE_TREE is set, call the WARN_ON_ONCE() after the
custom information is dumped about the tree.  Without using the kernel's
WARN_ON calls, syzbot will not catch issues detected by this code.

Update the non-debug code to call WARN_ON_ONCE() as well.

Cc: <stable at vger.kernel.org>
Reported-by: Lorenzo Stoakes <ljs at kernel.org>
Fixes: bf857ddd21d0b ("maple_tree: move debug check to __mas_set_range()")
Signed-off-by: Liam R. Howlett (Google) <liam at infradead.org>
---
 include/linux/maple_tree.h | 54 +++++++++++++++++++++-----------------
 1 file changed, 30 insertions(+), 24 deletions(-)

diff --git a/include/linux/maple_tree.h b/include/linux/maple_tree.h
index e30e57f5f3df9..0f96f1f19eb95 100644
--- a/include/linux/maple_tree.h
+++ b/include/linux/maple_tree.h
@@ -680,7 +680,7 @@ void mt_cache_shrink(void);
 		pr_info("Pass: %u Run:%u\n",				\
 			atomic_read(&maple_tree_tests_passed),		\
 			atomic_read(&maple_tree_tests_run));		\
-		dump_stack();						\
+		BUG_ON(1);						\
 	} else {							\
 		atomic_inc(&maple_tree_tests_passed);			\
 	}								\
@@ -696,7 +696,7 @@ void mt_cache_shrink(void);
 		pr_info("Pass: %u Run:%u\n",				\
 			atomic_read(&maple_tree_tests_passed),		\
 			atomic_read(&maple_tree_tests_run));		\
-		dump_stack();						\
+		BUG_ON(1);						\
 	} else {							\
 		atomic_inc(&maple_tree_tests_passed);			\
 	}								\
@@ -713,62 +713,68 @@ void mt_cache_shrink(void);
 		pr_info("Pass: %u Run:%u\n",				\
 			atomic_read(&maple_tree_tests_passed),		\
 			atomic_read(&maple_tree_tests_run));		\
-		dump_stack();						\
+		BUG_ON(1);						\
 	} else {							\
 		atomic_inc(&maple_tree_tests_passed);			\
 	}								\
 } while (0)
 
 #define MT_WARN_ON(__tree, __x)  ({					\
+	static bool __warned;						\
 	int ret = !!(__x);						\
 	atomic_inc(&maple_tree_tests_run);				\
-	if (ret) {							\
-		pr_info("WARN at %s:%d (%u)\n",				\
-		__func__, __LINE__, __x);				\
+	if (!ret) {							\
+		atomic_inc(&maple_tree_tests_passed);			\
+	} else if (!__warned) {						\
+		__warned = true;					\
+		pr_info("WARN at %s:%d\n",				\
+		__func__, __LINE__);					\
 		mt_dump(__tree, mt_dump_hex);				\
 		pr_info("Pass: %u Run:%u\n",				\
 			atomic_read(&maple_tree_tests_passed),		\
 			atomic_read(&maple_tree_tests_run));		\
-		dump_stack();						\
-	} else {							\
-		atomic_inc(&maple_tree_tests_passed);			\
+		WARN_ON(1);						\
 	}								\
 	unlikely(ret);							\
 })
 
 #define MAS_WARN_ON(__mas, __x) ({					\
+	static bool __warned;						\
 	int ret = !!(__x);						\
 	atomic_inc(&maple_tree_tests_run);				\
-	if (ret) {							\
-		pr_info("WARN at %s:%d (%u)\n",				\
-		__func__, __LINE__, __x);				\
+	if (!ret) {							\
+		atomic_inc(&maple_tree_tests_passed);			\
+	} else if (!__warned) {						\
+		__warned = true;					\
+		pr_info("WARN at %s:%d\n",				\
+		__func__, __LINE__);					\
 		mas_dump(__mas);					\
 		mt_dump((__mas)->tree, mt_dump_hex);			\
 		pr_info("Pass: %u Run:%u\n",				\
 			atomic_read(&maple_tree_tests_passed),		\
 			atomic_read(&maple_tree_tests_run));		\
-		dump_stack();						\
-	} else {							\
-		atomic_inc(&maple_tree_tests_passed);			\
+		WARN_ON(1);						\
 	}								\
 	unlikely(ret);							\
 })
 
 #define MAS_WR_WARN_ON(__wrmas, __x) ({					\
+	static bool __warned;						\
 	int ret = !!(__x);						\
 	atomic_inc(&maple_tree_tests_run);				\
-	if (ret) {							\
-		pr_info("WARN at %s:%d (%u)\n",				\
-		__func__, __LINE__, __x);				\
+	if (!ret) {							\
+		atomic_inc(&maple_tree_tests_passed);			\
+	} else if (!__warned) {						\
+		__warned = true;					\
+		pr_info("WARN at %s:%d\n",				\
+		__func__, __LINE__);					\
 		mas_wr_dump(__wrmas);					\
 		mas_dump((__wrmas)->mas);				\
 		mt_dump((__wrmas)->mas->tree, mt_dump_hex);		\
 		pr_info("Pass: %u Run:%u\n",				\
 			atomic_read(&maple_tree_tests_passed),		\
 			atomic_read(&maple_tree_tests_run));		\
-		dump_stack();						\
-	} else {							\
-		atomic_inc(&maple_tree_tests_passed);			\
+		WARN_ON(1);						\
 	}								\
 	unlikely(ret);							\
 })
@@ -776,9 +782,9 @@ void mt_cache_shrink(void);
 #define MT_BUG_ON(__tree, __x)		BUG_ON(__x)
 #define MAS_BUG_ON(__mas, __x)		BUG_ON(__x)
 #define MAS_WR_BUG_ON(__mas, __x)	BUG_ON(__x)
-#define MT_WARN_ON(__tree, __x)		WARN_ON(__x)
-#define MAS_WARN_ON(__mas, __x)		WARN_ON(__x)
-#define MAS_WR_WARN_ON(__mas, __x)	WARN_ON(__x)
+#define MT_WARN_ON(__tree, __x)		WARN_ON_ONCE(__x)
+#define MAS_WARN_ON(__mas, __x)		WARN_ON_ONCE(__x)
+#define MAS_WR_WARN_ON(__mas, __x)	WARN_ON_ONCE(__x)
 #endif /* CONFIG_DEBUG_MAPLE_TREE */
 
 /**
-- 
2.47.3