Revert "x86/bug: Macrofy the BUG table section handling, to work around GCC inlining bugs"

This reverts commit f81f8ad56f.

See this commit for details about the revert:

  e769742d35 ("Revert "x86/jump-labels: Macrofy inline assembly code to work around GCC inlining bugs"")

Reported-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Borislav Petkov <bp@alien8.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Juergen Gross <jgross@suse.com>
Cc: Richard Biener <rguenther@suse.de>
Cc: Kees Cook <keescook@chromium.org>
Cc: Segher Boessenkool <segher@kernel.crashing.org>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Nadav Amit <namit@vmware.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>

arch/x86/include/asm/bug.h

@@ -4,8 +4,6 @@
 
 #include <linux/stringify.h>
 
-#ifndef __ASSEMBLY__
-
 /*
  * Despite that some emulators terminate on UD2, we use it for WARN().
  *
@@ -22,15 +20,53 @@
 
 #define LEN_UD2		2
 
+#ifdef CONFIG_GENERIC_BUG
+
+#ifdef CONFIG_X86_32
+# define __BUG_REL(val)	".long " __stringify(val)
+#else
+# define __BUG_REL(val)	".long " __stringify(val) " - 2b"
+#endif
+
+#ifdef CONFIG_DEBUG_BUGVERBOSE
+
 #define _BUG_FLAGS(ins, flags)						\
 do {									\
-	asm volatile("ASM_BUG ins=\"" ins "\" file=%c0 line=%c1 "	\
+	asm volatile("1:\t" ins "\n"					\
-		     "flags=%c2 size=%c3"				\
+		     ".pushsection __bug_table,\"aw\"\n"		\
-		     : : "i" (__FILE__), "i" (__LINE__),                \
+		     "2:\t" __BUG_REL(1b) "\t# bug_entry::bug_addr\n"	\
-			 "i" (flags),                                   \
+		     "\t"  __BUG_REL(%c0) "\t# bug_entry::file\n"	\
+		     "\t.word %c1"        "\t# bug_entry::line\n"	\
+		     "\t.word %c2"        "\t# bug_entry::flags\n"	\
+		     "\t.org 2b+%c3\n"					\
+		     ".popsection"					\
+		     : : "i" (__FILE__), "i" (__LINE__),		\
+			 "i" (flags),					\
 			 "i" (sizeof(struct bug_entry)));		\
 } while (0)
 
+#else /* !CONFIG_DEBUG_BUGVERBOSE */
+
+#define _BUG_FLAGS(ins, flags)						\
+do {									\
+	asm volatile("1:\t" ins "\n"					\
+		     ".pushsection __bug_table,\"aw\"\n"		\
+		     "2:\t" __BUG_REL(1b) "\t# bug_entry::bug_addr\n"	\
+		     "\t.word %c0"        "\t# bug_entry::flags\n"	\
+		     "\t.org 2b+%c1\n"					\
+		     ".popsection"					\
+		     : : "i" (flags),					\
+			 "i" (sizeof(struct bug_entry)));		\
+} while (0)
+
+#endif /* CONFIG_DEBUG_BUGVERBOSE */
+
+#else
+
+#define _BUG_FLAGS(ins, flags)  asm volatile(ins)
+
+#endif /* CONFIG_GENERIC_BUG */
+
 #define HAVE_ARCH_BUG
 #define BUG()							\
 do {								\
@@ -46,54 +82,4 @@ do {								\
 
 #include <asm-generic/bug.h>
 
-#else /* __ASSEMBLY__ */
-
-#ifdef CONFIG_GENERIC_BUG
-
-#ifdef CONFIG_X86_32
-.macro __BUG_REL val:req
-	.long \val
-.endm
-#else
-.macro __BUG_REL val:req
-	.long \val - 2b
-.endm
-#endif
-
-#ifdef CONFIG_DEBUG_BUGVERBOSE
-
-.macro ASM_BUG ins:req file:req line:req flags:req size:req
-1:	\ins
-	.pushsection __bug_table,"aw"
-2:	__BUG_REL val=1b	# bug_entry::bug_addr
-	__BUG_REL val=\file	# bug_entry::file
-	.word \line		# bug_entry::line
-	.word \flags		# bug_entry::flags
-	.org 2b+\size
-	.popsection
-.endm
-
-#else /* !CONFIG_DEBUG_BUGVERBOSE */
-
-.macro ASM_BUG ins:req file:req line:req flags:req size:req
-1:	\ins
-	.pushsection __bug_table,"aw"
-2:	__BUG_REL val=1b	# bug_entry::bug_addr
-	.word \flags		# bug_entry::flags
-	.org 2b+\size
-	.popsection
-.endm
-
-#endif /* CONFIG_DEBUG_BUGVERBOSE */
-
-#else /* CONFIG_GENERIC_BUG */
-
-.macro ASM_BUG ins:req file:req line:req flags:req size:req
-	\ins
-.endm
-
-#endif /* CONFIG_GENERIC_BUG */
-
-#endif /* __ASSEMBLY__ */
-
 #endif /* _ASM_X86_BUG_H */

arch/x86/kernel/macros.S

@@ -9,4 +9,3 @@
 #include <linux/compiler.h>
 #include <asm/refcount.h>
 #include <asm/alternative-asm.h>
-#include <asm/bug.h>

include/asm-generic/bug.h

@@ -17,8 +17,10 @@
 #ifndef __ASSEMBLY__
 #include <linux/kernel.h>
 
-struct bug_entry {
+#ifdef CONFIG_BUG
+
 #ifdef CONFIG_GENERIC_BUG
+struct bug_entry {
 #ifndef CONFIG_GENERIC_BUG_RELATIVE_POINTERS
 	unsigned long	bug_addr;
 #else
@@ -33,10 +35,8 @@ struct bug_entry {
 	unsigned short	line;
 #endif
 	unsigned short	flags;
-#endif	/* CONFIG_GENERIC_BUG */
 };
-
+#endif	/* CONFIG_GENERIC_BUG */
-#ifdef CONFIG_BUG
 
 /*
  * Don't use BUG() or BUG_ON() unless there's really no way out; one