[PATCH 4.4 070/193] arm64: define BUG() instruction without CONFIG_BUG

From: Greg Kroah-Hartman
Date: Fri Feb 23 2018 - 13:36:04 EST


4.4-stable review patch. If anyone has any objections, please let me know.

------------------

From: Arnd Bergmann <arnd@xxxxxxxx>

commit f13d52cb3fad03c237572be2ee691e1fe2d1d7bb upstream.

This mirrors commit e9c38ceba8d9 ("ARM: 8455/1: define __BUG as
asm(BUG_INSTR) without CONFIG_BUG") to make the behavior of
arm64 consistent with arm and x86, and avoids lots of warnings in
randconfig builds, such as:

kernel/seccomp.c: In function '__seccomp_filter':
kernel/seccomp.c:666:1: error: no return statement in function returning non-void [-Werror=return-type]

Acked-by: Will Deacon <will.deacon@xxxxxxx>
Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
Signed-off-by: Catalin Marinas <catalin.marinas@xxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
arch/arm64/include/asm/bug.h | 35 ++++++++++++++++++++---------------
1 file changed, 20 insertions(+), 15 deletions(-)

--- a/arch/arm64/include/asm/bug.h
+++ b/arch/arm64/include/asm/bug.h
@@ -20,9 +20,6 @@

#include <asm/debug-monitors.h>

-#ifdef CONFIG_GENERIC_BUG
-#define HAVE_ARCH_BUG
-
#ifdef CONFIG_DEBUG_BUGVERBOSE
#define _BUGVERBOSE_LOCATION(file, line) __BUGVERBOSE_LOCATION(file, line)
#define __BUGVERBOSE_LOCATION(file, line) \
@@ -36,28 +33,36 @@
#define _BUGVERBOSE_LOCATION(file, line)
#endif

-#define _BUG_FLAGS(flags) __BUG_FLAGS(flags)
+#ifdef CONFIG_GENERIC_BUG

-#define __BUG_FLAGS(flags) asm volatile ( \
+#define __BUG_ENTRY(flags) \
".pushsection __bug_table,\"a\"\n\t" \
".align 2\n\t" \
"0: .long 1f - 0b\n\t" \
_BUGVERBOSE_LOCATION(__FILE__, __LINE__) \
".short " #flags "\n\t" \
".popsection\n" \
- \
- "1: brk %[imm]" \
- :: [imm] "i" (BUG_BRK_IMM) \
-)
-
-#define BUG() do { \
- _BUG_FLAGS(0); \
- unreachable(); \
+ "1: "
+#else
+#define __BUG_ENTRY(flags) ""
+#endif
+
+#define __BUG_FLAGS(flags) \
+ asm volatile ( \
+ __BUG_ENTRY(flags) \
+ "brk %[imm]" :: [imm] "i" (BUG_BRK_IMM) \
+ );
+
+
+#define BUG() do { \
+ __BUG_FLAGS(0); \
+ unreachable(); \
} while (0)

-#define __WARN_TAINT(taint) _BUG_FLAGS(BUGFLAG_TAINT(taint))
+#define __WARN_TAINT(taint) \
+ __BUG_FLAGS(BUGFLAG_TAINT(taint))

-#endif /* ! CONFIG_GENERIC_BUG */
+#define HAVE_ARCH_BUG

#include <asm-generic/bug.h>