Merge tag 'v4.17-rc3' into apparmor-next

Linux v4.17-rc3

Merge in v4.17 for LSM updates

Signed-off-by: John Johansen <john.johansen@canonical.com>

1 files changed, 26 insertions, 12 deletions

diff --git a/include/linux/compiler-gcc.h b/include/linux/compiler-gcc.h
index 631354acfa72..b4bf73f5e38f 100644
--- a/include/linux/compiler-gcc.h
+++ b/include/linux/compiler-gcc.h
@@ -93,6 +93,10 @@
 #define __weak		__attribute__((weak))
 #define __alias(symbol)	__attribute__((alias(#symbol)))
 
+#ifdef RETPOLINE
+#define __noretpoline __attribute__((indirect_branch("keep")))
+#endif
+
 /*
  * it doesn't make sense on ARM (currently the only user of __naked)
  * to trace naked functions because then mcount is called without
@@ -167,8 +171,6 @@
 
 #if GCC_VERSION >= 40100
 # define __compiletime_object_size(obj) __builtin_object_size(obj, 0)
-
-#define __nostackprotector	__attribute__((__optimize__("no-stack-protector")))
 #endif
 
 #if GCC_VERSION >= 40300
@@ -196,6 +198,11 @@
 #endif /* __CHECKER__ */
 #endif /* GCC_VERSION >= 40300 */
 
+#if GCC_VERSION >= 40400
+#define __optimize(level)	__attribute__((__optimize__(level)))
+#define __nostackprotector	__optimize("no-stack-protector")
+#endif /* GCC_VERSION >= 40400 */
+
 #if GCC_VERSION >= 40500
 
 #ifndef __CHECKER__
@@ -205,6 +212,15 @@
 #endif
 
 /*
+ * calling noreturn functions, __builtin_unreachable() and __builtin_trap()
+ * confuse the stack allocation in gcc, leading to overly large stack
+ * frames, see https://gcc.gnu.org/bugzilla/show_bug.cgi?id=82365
+ *
+ * Adding an empty inline assembly before it works around the problem
+ */
+#define barrier_before_unreachable() asm volatile("")
+
+/*
  * Mark a position in code as unreachable.  This can be used to
  * suppress control flow warnings after asm blocks that transfer
  * control elsewhere.
@@ -214,7 +230,11 @@
  * unreleased.  Really, we need to have autoconf for the kernel.
  */
 #define unreachable() \
-	do { annotate_unreachable(); __builtin_unreachable(); } while (0)
+	do {					\
+		annotate_unreachable();		\
+		barrier_before_unreachable();	\
+		__builtin_unreachable();	\
+	} while (0)
 
 /* Mark a function definition as prohibited from being cloned. */
 #define __noclone	__attribute__((__noclone__, __optimize__("no-tracer")))
@@ -222,6 +242,9 @@
 #if defined(RANDSTRUCT_PLUGIN) && !defined(__CHECKER__)
 #define __randomize_layout __attribute__((randomize_layout))
 #define __no_randomize_layout __attribute__((no_randomize_layout))
+/* This anon struct can add padding, so only enable it under randstruct. */
+#define randomized_struct_fields_start	struct {
+#define randomized_struct_fields_end	} __randomize_layout;
 #endif
 
 #endif /* GCC_VERSION >= 40500 */
@@ -236,15 +259,6 @@
  */
 #define __visible	__attribute__((externally_visible))
 
-/*
- * RANDSTRUCT_PLUGIN wants to use an anonymous struct, but it is only
- * possible since GCC 4.6. To provide as much build testing coverage
- * as possible, this is used for all GCC 4.6+ builds, and not just on
- * RANDSTRUCT_PLUGIN builds.
- */
-#define randomized_struct_fields_start	struct {
-#define randomized_struct_fields_end	} __randomize_layout;
-
 #endif /* GCC_VERSION >= 40600 */