objtool: Implement stack validation 2.0

This is a major rewrite of objtool.  Instead of only tracking frame
pointer changes, it now tracks all stack-related operations, including
all register saves/restores.

In addition to making stack validation more robust, this also paves the
way for undwarf generation.

Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: live-patching@vger.kernel.org
Link: http://lkml.kernel.org/r/678bd94c0566c6129bcc376cddb259c4c5633004.1498659915.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>

1 files changed, 51 insertions, 13 deletions

diff --git a/tools/objtool/arch.h b/tools/objtool/arch.h
index a59e061c0b4a..21aeca874edb 100644
--- a/tools/objtool/arch.h
+++ b/tools/objtool/arch.h
@@ -19,25 +19,63 @@
 #define _ARCH_H
 
 #include <stdbool.h>
+#include <linux/list.h>
 #include "elf.h"
+#include "cfi.h"
 
-#define INSN_FP_SAVE		1
-#define INSN_FP_SETUP		2
-#define INSN_FP_RESTORE		3
-#define INSN_JUMP_CONDITIONAL	4
-#define INSN_JUMP_UNCONDITIONAL	5
-#define INSN_JUMP_DYNAMIC	6
-#define INSN_CALL		7
-#define INSN_CALL_DYNAMIC	8
-#define INSN_RETURN		9
-#define INSN_CONTEXT_SWITCH	10
-#define INSN_NOP		11
-#define INSN_OTHER		12
+#define INSN_JUMP_CONDITIONAL	1
+#define INSN_JUMP_UNCONDITIONAL	2
+#define INSN_JUMP_DYNAMIC	3
+#define INSN_CALL		4
+#define INSN_CALL_DYNAMIC	5
+#define INSN_RETURN		6
+#define INSN_CONTEXT_SWITCH	7
+#define INSN_STACK		8
+#define INSN_NOP		9
+#define INSN_OTHER		10
 #define INSN_LAST		INSN_OTHER
 
+enum op_dest_type {
+	OP_DEST_REG,
+	OP_DEST_REG_INDIRECT,
+	OP_DEST_MEM,
+	OP_DEST_PUSH,
+	OP_DEST_LEAVE,
+};
+
+struct op_dest {
+	enum op_dest_type type;
+	unsigned char reg;
+	int offset;
+};
+
+enum op_src_type {
+	OP_SRC_REG,
+	OP_SRC_REG_INDIRECT,
+	OP_SRC_CONST,
+	OP_SRC_POP,
+	OP_SRC_ADD,
+	OP_SRC_AND,
+};
+
+struct op_src {
+	enum op_src_type type;
+	unsigned char reg;
+	int offset;
+};
+
+struct stack_op {
+	struct op_dest dest;
+	struct op_src src;
+};
+
+void arch_initial_func_cfi_state(struct cfi_state *state);
+
 int arch_decode_instruction(struct elf *elf, struct section *sec,
 			    unsigned long offset, unsigned int maxlen,
 			    unsigned int *len, unsigned char *type,
-			    unsigned long *displacement);
+			    unsigned long *immediate, struct stack_op *op);
+
+bool arch_callee_saved_reg(unsigned char reg);
 
 #endif /* _ARCH_H */