[PATCH v6 16/39] kmsan: Expose KMSAN_WARN_ON()

Ilya Leoshkevich
2024-06-21T00:27:08Z

KMSAN_WARN_ON() is required for implementing s390-specific KMSAN
functions, but right now it's available only to the KMSAN internal
functions. Expose it to subsystems through <linux/kmsan.h>.

Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
---
include/linux/kmsan.h | 25 +++++++++++++++++++++++++
mm/kmsan/kmsan.h | 24 +-----------------------
2 files changed, 26 insertions(+), 23 deletions(-)

diff --git a/include/linux/kmsan.h b/include/linux/kmsan.h
index 7109644f4c19..2b1432cc16d5 100644
--- a/include/linux/kmsan.h
+++ b/include/linux/kmsan.h
@@ -268,6 +268,29 @@ static inline void *memset_no_sanitize_memory(void *s, int c, size_t n)
return __memset(s, c, n);
}

+extern bool kmsan_enabled;
+extern int panic_on_kmsan;
+
+/*
+ * KMSAN performs a lot of consistency checks that are currently enabled by
+ * default. BUG_ON is normally discouraged in the kernel, unless used for
+ * debugging, but KMSAN itself is a debugging tool, so it makes little sense to
+ * recover if something goes wrong.
+ */
+#define KMSAN_WARN_ON(cond) \
+ ({ \
+ const bool __cond = WARN_ON(cond); \
+ if (unlikely(__cond)) { \
+ WRITE_ONCE(kmsan_enabled, false); \
+ if (panic_on_kmsan) { \
+ /* Can't call panic() here because */ \
+ /* of uaccess checks. */ \
+ BUG(); \
+ } \
+ } \
+ __cond; \
+ })
+
#else

static inline void kmsan_init_shadow(void)
@@ -380,6 +403,8 @@ static inline void *memset_no_sanitize_memory(void *s, int c, size_t n)
return memset(s, c, n);
}

+#define KMSAN_WARN_ON WARN_ON
+
#endif

#endif /* _LINUX_KMSAN_H */
diff --git a/mm/kmsan/kmsan.h b/mm/kmsan/kmsan.h
index 34b83c301d57..91a360a31e85 100644
--- a/mm/kmsan/kmsan.h
+++ b/mm/kmsan/kmsan.h
@@ -11,6 +11,7 @@
#define __MM_KMSAN_KMSAN_H

#include <linux/irqflags.h>
+#include <linux/kmsan.h>
#include <linux/mm.h>
#include <linux/nmi.h>
#include <linux/pgtable.h>
@@ -34,29 +35,6 @@
#define KMSAN_META_SHADOW (false)
#define KMSAN_META_ORIGIN (true)

-extern bool kmsan_enabled;
-extern int panic_on_kmsan;
-
-/*
- * KMSAN performs a lot of consistency checks that are currently enabled by
- * default. BUG_ON is normally discouraged in the kernel, unless used for
- * debugging, but KMSAN itself is a debugging tool, so it makes little sense to
- * recover if something goes wrong.
- */
-#define KMSAN_WARN_ON(cond) \
- ({ \
- const bool __cond = WARN_ON(cond); \
- if (unlikely(__cond)) { \
- WRITE_ONCE(kmsan_enabled, false); \
- if (panic_on_kmsan) { \
- /* Can't call panic() here because */ \
- /* of uaccess checks. */ \
- BUG(); \
- } \
- } \
- __cond; \
- })
-
/*
* A pair of metadata pointers to be returned by the instrumentation functions.
*/
--
2.45.1