Merge tag 'objtool-core-2021-04-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull objtool updates from Ingo Molnar:

 - Standardize the crypto asm code so that it looks like compiler-
   generated code to objtool - so that it can understand it. This
   enables unwinding from crypto asm code - and also fixes the last
   known remaining objtool warnings for LTO and more.

 - x86 decoder fixes: clean up and fix the decoder, and also extend it a
   bit

 - Misc fixes and cleanups

* tag 'objtool-core-2021-04-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (24 commits)
  x86/crypto: Enable objtool in crypto code
  x86/crypto/sha512-ssse3: Standardize stack alignment prologue
  x86/crypto/sha512-avx2: Standardize stack alignment prologue
  x86/crypto/sha512-avx: Standardize stack alignment prologue
  x86/crypto/sha256-avx2: Standardize stack alignment prologue
  x86/crypto/sha1_avx2: Standardize stack alignment prologue
  x86/crypto/sha_ni: Standardize stack alignment prologue
  x86/crypto/crc32c-pcl-intel: Standardize jump table
  x86/crypto/camellia-aesni-avx2: Unconditionally allocate stack buffer
  x86/crypto/aesni-intel_avx: Standardize stack alignment prologue
  x86/crypto/aesni-intel_avx: Fix register usage comments
  x86/crypto/aesni-intel_avx: Remove unused macros
  objtool: Support asm jump tables
  objtool: Parse options from OBJTOOL_ARGS
  objtool: Collate parse_options() users
  objtool: Add --backup
  objtool,x86: More ModRM sugar
  objtool,x86: Rewrite ADD/SUB/AND
  objtool,x86: Support %riz encodings
  objtool,x86: Simplify register decode
  ...

8 files changed, 299 insertions, 166 deletions

diff --git a/tools/objtool/arch/x86/decode.c b/tools/objtool/arch/x86/decode.c
index 7e8b5bedd946..cedf3ede7545 100644
--- a/tools/objtool/arch/x86/decode.c
+++ b/tools/objtool/arch/x86/decode.c
@@ -21,17 +21,6 @@
 #include <objtool/warn.h>
 #include <arch/elf.h>
 
-static unsigned char op_to_cfi_reg[][2] = {
-	{CFI_AX, CFI_R8},
-	{CFI_CX, CFI_R9},
-	{CFI_DX, CFI_R10},
-	{CFI_BX, CFI_R11},
-	{CFI_SP, CFI_R12},
-	{CFI_BP, CFI_R13},
-	{CFI_SI, CFI_R14},
-	{CFI_DI, CFI_R15},
-};
-
 static int is_x86_64(const struct elf *elf)
 {
 	switch (elf->ehdr.e_machine) {
@@ -87,6 +76,31 @@ unsigned long arch_jump_destination(struct instruction *insn)
 		return -1; \
 	else for (list_add_tail(&op->list, ops_list); op; op = NULL)
 
+/*
+ * Helpers to decode ModRM/SIB:
+ *
+ * r/m| AX  CX  DX  BX |  SP |  BP |  SI  DI |
+ *    | R8  R9 R10 R11 | R12 | R13 | R14 R15 |
+ * Mod+----------------+-----+-----+---------+
+ * 00 |    [r/m]       |[SIB]|[IP+]|  [r/m]  |
+ * 01 |  [r/m + d8]    |[S+d]|   [r/m + d8]  |
+ * 10 |  [r/m + d32]   |[S+D]|   [r/m + d32] |
+ * 11 |                   r/ m               |
+ */
+
+#define mod_is_mem()	(modrm_mod != 3)
+#define mod_is_reg()	(modrm_mod == 3)
+
+#define is_RIP()   ((modrm_rm & 7) == CFI_BP && modrm_mod == 0)
+#define have_SIB() ((modrm_rm & 7) == CFI_SP && mod_is_mem())
+
+#define rm_is(reg) (have_SIB() ? \
+		    sib_base == (reg) && sib_index == CFI_SP : \
+		    modrm_rm == (reg))
+
+#define rm_is_mem(reg)	(mod_is_mem() && !is_RIP() && rm_is(reg))
+#define rm_is_reg(reg)	(mod_is_reg() && modrm_rm == (reg))
+
 int arch_decode_instruction(const struct elf *elf, const struct section *sec,
 			    unsigned long offset, unsigned int maxlen,
 			    unsigned int *len, enum insn_type *type,
@@ -94,12 +108,14 @@ int arch_decode_instruction(const struct elf *elf, const struct section *sec,
 			    struct list_head *ops_list)
 {
 	struct insn insn;
-	int x86_64, sign, ret;
-	unsigned char op1, op2, rex = 0, rex_b = 0, rex_r = 0, rex_w = 0,
-		      rex_x = 0, modrm = 0, modrm_mod = 0, modrm_rm = 0,
-		      modrm_reg = 0, sib = 0;
+	int x86_64, ret;
+	unsigned char op1, op2,
+		      rex = 0, rex_b = 0, rex_r = 0, rex_w = 0, rex_x = 0,
+		      modrm = 0, modrm_mod = 0, modrm_rm = 0, modrm_reg = 0,
+		      sib = 0, /* sib_scale = 0, */ sib_index = 0, sib_base = 0;
 	struct stack_op *op = NULL;
 	struct symbol *sym;
+	u64 imm;
 
 	x86_64 = is_x86_64(elf);
 	if (x86_64 == -1)
@@ -132,23 +148,27 @@ int arch_decode_instruction(const struct elf *elf, const struct section *sec,
 	if (insn.modrm.nbytes) {
 		modrm = insn.modrm.bytes[0];
 		modrm_mod = X86_MODRM_MOD(modrm);
-		modrm_reg = X86_MODRM_REG(modrm);
-		modrm_rm = X86_MODRM_RM(modrm);
+		modrm_reg = X86_MODRM_REG(modrm) + 8*rex_r;
+		modrm_rm  = X86_MODRM_RM(modrm)  + 8*rex_b;
 	}
 
-	if (insn.sib.nbytes)
+	if (insn.sib.nbytes) {
 		sib = insn.sib.bytes[0];
+		/* sib_scale = X86_SIB_SCALE(sib); */
+		sib_index = X86_SIB_INDEX(sib) + 8*rex_x;
+		sib_base  = X86_SIB_BASE(sib)  + 8*rex_b;
+	}
 
 	switch (op1) {
 
 	case 0x1:
 	case 0x29:
-		if (rex_w && !rex_b && modrm_mod == 3 && modrm_rm == 4) {
+		if (rex_w && rm_is_reg(CFI_SP)) {
 
 			/* add/sub reg, %rsp */
 			ADD_OP(op) {
 				op->src.type = OP_SRC_ADD;
-				op->src.reg = op_to_cfi_reg[modrm_reg][rex_r];
+				op->src.reg = modrm_reg;
 				op->dest.type = OP_DEST_REG;
 				op->dest.reg = CFI_SP;
 			}
@@ -160,7 +180,7 @@ int arch_decode_instruction(const struct elf *elf, const struct section *sec,
 		/* push reg */
 		ADD_OP(op) {
 			op->src.type = OP_SRC_REG;
-			op->src.reg = op_to_cfi_reg[op1 & 0x7][rex_b];
+			op->src.reg = (op1 & 0x7) + 8*rex_b;
 			op->dest.type = OP_DEST_PUSH;
 		}
 
@@ -172,7 +192,7 @@ int arch_decode_instruction(const struct elf *elf, const struct section *sec,
 		ADD_OP(op) {
 			op->src.type = OP_SRC_POP;
 			op->dest.type = OP_DEST_REG;
-			op->dest.reg = op_to_cfi_reg[op1 & 0x7][rex_b];
+			op->dest.reg = (op1 & 0x7) + 8*rex_b;
 		}
 
 		break;
@@ -190,12 +210,54 @@ int arch_decode_instruction(const struct elf *elf, const struct section *sec,
 		*type = INSN_JUMP_CONDITIONAL;
 		break;
 
-	case 0x81:
-	case 0x83:
-		if (rex != 0x48)
+	case 0x80 ... 0x83:
+		/*
+		 * 1000 00sw : mod OP r/m : immediate
+		 *
+		 * s - sign extend immediate
+		 * w - imm8 / imm32
+		 *
+		 * OP: 000 ADD    100 AND
+		 *     001 OR     101 SUB
+		 *     010 ADC    110 XOR
+		 *     011 SBB    111 CMP
+		 */
+
+		/* 64bit only */
+		if (!rex_w)
+			break;
+
+		/* %rsp target only */
+		if (!rm_is_reg(CFI_SP))
 			break;
 
-		if (modrm == 0xe4) {
+		imm = insn.immediate.value;
+		if (op1 & 2) { /* sign extend */
+			if (op1 & 1) { /* imm32 */
+				imm <<= 32;
+				imm = (s64)imm >> 32;
+			} else { /* imm8 */
+				imm <<= 56;
+				imm = (s64)imm >> 56;
+			}
+		}
+
+		switch (modrm_reg & 7) {
+		case 5:
+			imm = -imm;
+			/* fallthrough */
+		case 0:
+			/* add/sub imm, %rsp */
+			ADD_OP(op) {
+				op->src.type = OP_SRC_ADD;
+				op->src.reg = CFI_SP;
+				op->src.offset = imm;
+				op->dest.type = OP_DEST_REG;
+				op->dest.reg = CFI_SP;
+			}
+			break;
+
+		case 4:
 			/* and imm, %rsp */
 			ADD_OP(op) {
 				op->src.type = OP_SRC_AND;
@@ -205,53 +267,48 @@ int arch_decode_instruction(const struct elf *elf, const struct section *sec,
 				op->dest.reg = CFI_SP;
 			}
 			break;
-		}
 
-		if (modrm == 0xc4)
-			sign = 1;
-		else if (modrm == 0xec)
-			sign = -1;
-		else
+		default:
+			/* WARN ? */
 			break;
-
-		/* add/sub imm, %rsp */
-		ADD_OP(op) {
-			op->src.type = OP_SRC_ADD;
-			op->src.reg = CFI_SP;
-			op->src.offset = insn.immediate.value * sign;
-			op->dest.type = OP_DEST_REG;
-			op->dest.reg = CFI_SP;
 		}
+
 		break;
 
 	case 0x89:
-		if (rex_w && !rex_r && modrm_reg == 4) {
+		if (!rex_w)
+			break;
+
+		if (modrm_reg == CFI_SP) {
 
-			if (modrm_mod == 3) {
+			if (mod_is_reg()) {
 				/* mov %rsp, reg */
 				ADD_OP(op) {
 					op->src.type = OP_SRC_REG;
 					op->src.reg = CFI_SP;
 					op->dest.type = OP_DEST_REG;
-					op->dest.reg = op_to_cfi_reg[modrm_rm][rex_b];
+					op->dest.reg = modrm_rm;
 				}
 				break;
 
 			} else {
-				/* skip nontrivial SIB */
-				if (modrm_rm == 4 && !(sib == 0x24 && rex_b == rex_x))
-					break;
-
 				/* skip RIP relative displacement */
-				if (modrm_rm == 5 && modrm_mod == 0)
+				if (is_RIP())
 					break;
 
+				/* skip nontrivial SIB */
+				if (have_SIB()) {
+					modrm_rm = sib_base;
+					if (sib_index != CFI_SP)
+						break;
+				}
+
 				/* mov %rsp, disp(%reg) */
 				ADD_OP(op) {
 					op->src.type = OP_SRC_REG;
 					op->src.reg = CFI_SP;
 					op->dest.type = OP_DEST_REG_INDIRECT;
-					op->dest.reg = op_to_cfi_reg[modrm_rm][rex_b];
+					op->dest.reg = modrm_rm;
 					op->dest.offset = insn.displacement.value;
 				}
 				break;
@@ -260,12 +317,12 @@ int arch_decode_instruction(const struct elf *elf, const struct section *sec,
 			break;
 		}
 
-		if (rex_w && !rex_b && modrm_mod == 3 && modrm_rm == 4) {
+		if (rm_is_reg(CFI_SP)) {
 
 			/* mov reg, %rsp */
 			ADD_OP(op) {
 				op->src.type = OP_SRC_REG;
-				op->src.reg = op_to_cfi_reg[modrm_reg][rex_r];
+				op->src.reg = modrm_reg;
 				op->dest.type = OP_DEST_REG;
 				op->dest.reg = CFI_SP;
 			}
@@ -274,13 +331,15 @@ int arch_decode_instruction(const struct elf *elf, const struct section *sec,
 
 		/* fallthrough */
 	case 0x88:
-		if (!rex_b &&
-		    (modrm_mod == 1 || modrm_mod == 2) && modrm_rm == 5) {
+		if (!rex_w)
+			break;
+
+		if (rm_is_mem(CFI_BP)) {
 
 			/* mov reg, disp(%rbp) */
 			ADD_OP(op) {
 				op->src.type = OP_SRC_REG;
-				op->src.reg = op_to_cfi_reg[modrm_reg][rex_r];
+				op->src.reg = modrm_reg;
 				op->dest.type = OP_DEST_REG_INDIRECT;
 				op->dest.reg = CFI_BP;
 				op->dest.offset = insn.displacement.value;
@@ -288,12 +347,12 @@ int arch_decode_instruction(const struct elf *elf, const struct section *sec,
 			break;
 		}
 
-		if (rex_w && !rex_b && modrm_rm == 4 && sib == 0x24) {
+		if (rm_is_mem(CFI_SP)) {
 
 			/* mov reg, disp(%rsp) */
 			ADD_OP(op) {
 				op->src.type = OP_SRC_REG;
-				op->src.reg = op_to_cfi_reg[modrm_reg][rex_r];
+				op->src.reg = modrm_reg;
 				op->dest.type = OP_DEST_REG_INDIRECT;
 				op->dest.reg = CFI_SP;
 				op->dest.offset = insn.displacement.value;
@@ -304,7 +363,10 @@ int arch_decode_instruction(const struct elf *elf, const struct section *sec,
 		break;
 
 	case 0x8b:
-		if (rex_w && !rex_b && modrm_mod == 1 && modrm_rm == 5) {
+		if (!rex_w)
+			break;
+
+		if (rm_is_mem(CFI_BP)) {
 
 			/* mov disp(%rbp), reg */
 			ADD_OP(op) {
@@ -312,11 +374,12 @@ int arch_decode_instruction(const struct elf *elf, const struct section *sec,
 				op->src.reg = CFI_BP;
 				op->src.offset = insn.displacement.value;
 				op->dest.type = OP_DEST_REG;
-				op->dest.reg = op_to_cfi_reg[modrm_reg][rex_r];
+				op->dest.reg = modrm_reg;
 			}
+			break;
+		}
 
-		} else if (rex_w && !rex_b && sib == 0x24 &&
-			   modrm_mod != 3 && modrm_rm == 4) {
+		if (rm_is_mem(CFI_SP)) {
 
 			/* mov disp(%rsp), reg */
 			ADD_OP(op) {
@@ -324,75 +387,48 @@ int arch_decode_instruction(const struct elf *elf, const struct section *sec,
 				op->src.reg = CFI_SP;
 				op->src.offset = insn.displacement.value;
 				op->dest.type = OP_DEST_REG;
-				op->dest.reg = op_to_cfi_reg[modrm_reg][rex_r];
+				op->dest.reg = modrm_reg;
 			}
+			break;
 		}
 
 		break;
 
 	case 0x8d:
-		if (sib == 0x24 && rex_w && !rex_b && !rex_x) {
-
-			ADD_OP(op) {
-				if (!insn.displacement.value) {
-					/* lea (%rsp), reg */
-					op->src.type = OP_SRC_REG;
-				} else {
-					/* lea disp(%rsp), reg */
-					op->src.type = OP_SRC_ADD;
-					op->src.offset = insn.displacement.value;
-				}
-				op->src.reg = CFI_SP;
-				op->dest.type = OP_DEST_REG;
-				op->dest.reg = op_to_cfi_reg[modrm_reg][rex_r];
-			}
-
-		} else if (rex == 0x48 && modrm == 0x65) {
-
-			/* lea disp(%rbp), %rsp */
-			ADD_OP(op) {
-				op->src.type = OP_SRC_ADD;
-				op->src.reg = CFI_BP;
-				op->src.offset = insn.displacement.value;
-				op->dest.type = OP_DEST_REG;
-				op->dest.reg = CFI_SP;
-			}
+		if (mod_is_reg()) {
+			WARN("invalid LEA encoding at %s:0x%lx", sec->name, offset);
+			break;
+		}
 
-		} else if (rex == 0x49 && modrm == 0x62 &&
-			   insn.displacement.value == -8) {
+		/* skip non 64bit ops */
+		if (!rex_w)
+			break;
 
-			/*
-			 * lea -0x8(%r10), %rsp
-			 *
-			 * Restoring rsp back to its original value after a
-			 * stack realignment.
-			 */
-			ADD_OP(op) {
-				op->src.type = OP_SRC_ADD;
-				op->src.reg = CFI_R10;
-				op->src.offset = -8;
-				op->dest.type = OP_DEST_REG;
-				op->dest.reg = CFI_SP;
-			}
+		/* skip RIP relative displacement */
+		if (is_RIP())
+			break;
 
-		} else if (rex == 0x49 && modrm == 0x65 &&
-			   insn.displacement.value == -16) {
+		/* skip nontrivial SIB */
+		if (have_SIB()) {
+			modrm_rm = sib_base;
+			if (sib_index != CFI_SP)
+				break;
+		}
 
-			/*
-			 * lea -0x10(%r13), %rsp
-			 *
-			 * Restoring rsp back to its original value after a
-			 * stack realignment.
-			 */
-			ADD_OP(op) {
+		/* lea disp(%src), %dst */
+		ADD_OP(op) {
+			op->src.offset = insn.displacement.value;
+			if (!op->src.offset) {
+				/* lea (%src), %dst */
+				op->src.type = OP_SRC_REG;
+			} else {
+				/* lea disp(%src), %dst */
 				op->src.type = OP_SRC_ADD;
-				op->src.reg = CFI_R13;
-				op->src.offset = -16;
-				op->dest.type = OP_DEST_REG;
-				op->dest.reg = CFI_SP;
 			}
+			op->src.reg = modrm_rm;
+			op->dest.type = OP_DEST_REG;
+			op->dest.reg = modrm_reg;
 		}
-
 		break;
 
 	case 0x8f:
@@ -479,9 +515,17 @@ int arch_decode_instruction(const struct elf *elf, const struct section *sec,
 		 * mov bp, sp
 		 * pop bp
 		 */
-		ADD_OP(op)
-			op->dest.type = OP_DEST_LEAVE;
-
+		ADD_OP(op) {
+			op->src.type = OP_SRC_REG;
+			op->src.reg = CFI_BP;
+			op->dest.type = OP_DEST_REG;
+			op->dest.reg = CFI_SP;
+		}
+		ADD_OP(op) {
+			op->src.type = OP_SRC_POP;
+			op->dest.type = OP_DEST_REG;
+			op->dest.reg = CFI_BP;
+		}
 		break;
 
 	case 0xe3:
diff --git a/tools/objtool/arch/x86/include/arch/cfi_regs.h b/tools/objtool/arch/x86/include/arch/cfi_regs.h
index 79bc517efba8..0579d22c433c 100644
--- a/tools/objtool/arch/x86/include/arch/cfi_regs.h
+++ b/tools/objtool/arch/x86/include/arch/cfi_regs.h
@@ -4,13 +4,13 @@
 #define _OBJTOOL_CFI_REGS_H
 
 #define CFI_AX			0
-#define CFI_DX			1
-#define CFI_CX			2
+#define CFI_CX			1
+#define CFI_DX			2
 #define CFI_BX			3
-#define CFI_SI			4
-#define CFI_DI			5
-#define CFI_BP			6
-#define CFI_SP			7
+#define CFI_SP			4
+#define CFI_BP			5
+#define CFI_SI			6
+#define CFI_DI			7
 #define CFI_R8			8
 #define CFI_R9			9
 #define CFI_R10			10
diff --git a/tools/objtool/builtin-check.c b/tools/objtool/builtin-check.c
index c3a85d8f6c5c..8b38b5d6fec7 100644
--- a/tools/objtool/builtin-check.c
+++ b/tools/objtool/builtin-check.c
@@ -15,16 +15,23 @@
 
 #include <subcmd/parse-options.h>
 #include <string.h>
+#include <stdlib.h>
 #include <objtool/builtin.h>
 #include <objtool/objtool.h>
 
-bool no_fp, no_unreachable, retpoline, module, backtrace, uaccess, stats, validate_dup, vmlinux, mcount, noinstr;
+bool no_fp, no_unreachable, retpoline, module, backtrace, uaccess, stats,
+     validate_dup, vmlinux, mcount, noinstr, backup;
 
 static const char * const check_usage[] = {
 	"objtool check [<options>] file.o",
 	NULL,
 };
 
+static const char * const env_usage[] = {
+	"OBJTOOL_ARGS=\"<options>\"",
+	NULL,
+};
+
 const struct option check_options[] = {
 	OPT_BOOLEAN('f', "no-fp", &no_fp, "Skip frame pointer validation"),
 	OPT_BOOLEAN('u', "no-unreachable", &no_unreachable, "Skip 'unreachable instruction' warnings"),
@@ -37,20 +44,44 @@ const struct option check_options[] = {
 	OPT_BOOLEAN('n', "noinstr", &noinstr, "noinstr validation for vmlinux.o"),
 	OPT_BOOLEAN('l', "vmlinux", &vmlinux, "vmlinux.o validation"),
 	OPT_BOOLEAN('M', "mcount", &mcount, "generate __mcount_loc"),
+	OPT_BOOLEAN('B', "backup", &backup, "create .orig files before modification"),
 	OPT_END(),
 };
 
+int cmd_parse_options(int argc, const char **argv, const char * const usage[])
+{
+	const char *envv[16] = { };
+	char *env;
+	int envc;
+
+	env = getenv("OBJTOOL_ARGS");
+	if (env) {
+		envv[0] = "OBJTOOL_ARGS";
+		for (envc = 1; envc < ARRAY_SIZE(envv); ) {
+			envv[envc++] = env;
+			env = strchr(env, ' ');
+			if (!env)
+				break;
+			*env = '\0';
+			env++;
+		}
+
+		parse_options(envc, envv, check_options, env_usage, 0);
+	}
+
+	argc = parse_options(argc, argv, check_options, usage, 0);
+	if (argc != 1)
+		usage_with_options(usage, check_options);
+	return argc;
+}
+
 int cmd_check(int argc, const char **argv)
 {
 	const char *objname;
 	struct objtool_file *file;
 	int ret;
 
-	argc = parse_options(argc, argv, check_options, check_usage, 0);
-
-	if (argc != 1)
-		usage_with_options(check_usage, check_options);
-
+	argc = cmd_parse_options(argc, argv, check_usage);
 	objname = argv[0];
 
 	file = objtool_open_read(objname);
diff --git a/tools/objtool/builtin-orc.c b/tools/objtool/builtin-orc.c
index 8273bbf7cebb..17f8b9307738 100644
--- a/tools/objtool/builtin-orc.c
+++ b/tools/objtool/builtin-orc.c
@@ -34,10 +34,7 @@ int cmd_orc(int argc, const char **argv)
 		struct objtool_file *file;
 		int ret;
 
-		argc = parse_options(argc, argv, check_options, orc_usage, 0);
-		if (argc != 1)
-			usage_with_options(orc_usage, check_options);
-
+		argc = cmd_parse_options(argc, argv, orc_usage);
 		objname = argv[0];
 
 		file = objtool_open_read(objname);
diff --git a/tools/objtool/check.c b/tools/objtool/check.c
index 1f4154f9b04b..9ed1a4cd00dc 100644
--- a/tools/objtool/check.c
+++ b/tools/objtool/check.c
@@ -108,6 +108,18 @@ static struct instruction *prev_insn_same_sym(struct objtool_file *file,
 	for (insn = next_insn_same_sec(file, insn); insn;		\
 	     insn = next_insn_same_sec(file, insn))
 
+static bool is_jump_table_jump(struct instruction *insn)
+{
+	struct alt_group *alt_group = insn->alt_group;
+
+	if (insn->jump_table)
+		return true;
+
+	/* Retpoline alternative for a jump table? */
+	return alt_group && alt_group->orig_group &&
+	       alt_group->orig_group->first_insn->jump_table;
+}
+
 static bool is_sibling_call(struct instruction *insn)
 {
 	/*
@@ -120,7 +132,7 @@ static bool is_sibling_call(struct instruction *insn)
 
 	/* An indirect jump is either a sibling call or a jump to a table. */
 	if (insn->type == INSN_JUMP_DYNAMIC)
-		return list_empty(&insn->alts);
+		return !is_jump_table_jump(insn);
 
 	/* add_jump_destinations() sets insn->call_dest for sibling calls. */
 	return (is_static_jump(insn) && insn->call_dest);
@@ -1969,8 +1981,9 @@ static void restore_reg(struct cfi_state *cfi, unsigned char reg)
  *   41 5d			pop    %r13
  *   c3				retq
  */
-static int update_cfi_state(struct instruction *insn, struct cfi_state *cfi,
-			     struct stack_op *op)
+static int update_cfi_state(struct instruction *insn,
+			    struct instruction *next_insn,
+			    struct cfi_state *cfi, struct stack_op *op)
 {
 	struct cfi_reg *cfa = &cfi->cfa;
 	struct cfi_reg *regs = cfi->regs;
@@ -2029,7 +2042,7 @@ static int update_cfi_state(struct instruction *insn, struct cfi_state *cfi,
 			}
 
 			else if (op->src.reg == CFI_BP && op->dest.reg == CFI_SP &&
-				 cfa->base == CFI_BP) {
+				 (cfa->base == CFI_BP || cfa->base == cfi->drap_reg)) {
 
 				/*
 				 * mov %rbp, %rsp
@@ -2171,7 +2184,7 @@ static int update_cfi_state(struct instruction *insn, struct cfi_state *cfi,
 				break;
 			}
 
-			if (op->dest.reg == cfi->cfa.base) {
+			if (op->dest.reg == cfi->cfa.base && !(next_insn && next_insn->hint)) {
 				WARN_FUNC("unsupported stack register modification",
 					  insn->sec, insn->offset);
 				return -1;
@@ -2226,7 +2239,7 @@ static int update_cfi_state(struct instruction *insn, struct cfi_state *cfi,
 				cfa->offset = 0;
 				cfi->drap_offset = -1;
 
-			} else if (regs[op->dest.reg].offset == -cfi->stack_size) {
+			} else if (cfi->stack_size == -regs[op->dest.reg].offset) {
 
 				/* pop %reg */
 				restore_reg(cfi, op->dest.reg);
@@ -2367,26 +2380,6 @@ static int update_cfi_state(struct instruction *insn, struct cfi_state *cfi,
 
 		break;
 
-	case OP_DEST_LEAVE:
-		if ((!cfi->drap && cfa->base != CFI_BP) ||
-		    (cfi->drap && cfa->base != cfi->drap_reg)) {
-			WARN_FUNC("leave instruction with modified stack frame",
-				  insn->sec, insn->offset);
-			return -1;
-		}
-
-		/* leave (mov %rbp, %rsp; pop %rbp) */
-
-		cfi->stack_size = -cfi->regs[CFI_BP].offset - 8;
-		restore_reg(cfi, CFI_BP);
-
-		if (!cfi->drap) {
-			cfa->base = CFI_SP;
-			cfa->offset -= 8;
-		}
-
-		break;
-
 	case OP_DEST_MEM:
 		if (op->src.type != OP_SRC_POP && op->src.type != OP_SRC_POPF) {
 			WARN_FUNC("unknown stack-related memory operation",
@@ -2443,13 +2436,15 @@ static int propagate_alt_cfi(struct objtool_file *file, struct instruction *insn
 	return 0;
 }
 
-static int handle_insn_ops(struct instruction *insn, struct insn_state *state)
+static int handle_insn_ops(struct instruction *insn,
+			   struct instruction *next_insn,
+			   struct insn_state *state)
 {
 	struct stack_op *op;
 
 	list_for_each_entry(op, &insn->stack_ops, list) {
 
-		if (update_cfi_state(insn, &state->cfi, op))
+		if (update_cfi_state(insn, next_insn, &state->cfi, op))
 			return 1;
 
 		if (!insn->alt_group)
@@ -2732,7 +2727,7 @@ static int validate_branch(struct objtool_file *file, struct symbol *func,
 				return 0;
 		}
 
-		if (handle_insn_ops(insn, &state))
+		if (handle_insn_ops(insn, next_insn, &state))
 			return 1;
 
 		switch (insn->type) {
diff --git a/tools/objtool/include/objtool/arch.h b/tools/objtool/include/objtool/arch.h
index 48b540a9d9e9..062bb6e9b865 100644
--- a/tools/objtool/include/objtool/arch.h
+++ b/tools/objtool/include/objtool/arch.h
@@ -35,7 +35,6 @@ enum op_dest_type {
 	OP_DEST_MEM,
 	OP_DEST_PUSH,
 	OP_DEST_PUSHF,
-	OP_DEST_LEAVE,
 };
 
 struct op_dest {
diff --git a/tools/objtool/include/objtool/builtin.h b/tools/objtool/include/objtool/builtin.h
index 2502bb27de17..15ac0b7d3d6a 100644
--- a/tools/objtool/include/objtool/builtin.h
+++ b/tools/objtool/include/objtool/builtin.h
@@ -8,7 +8,10 @@
 #include <subcmd/parse-options.h>
 
 extern const struct option check_options[];
-extern bool no_fp, no_unreachable, retpoline, module, backtrace, uaccess, stats, validate_dup, vmlinux, mcount, noinstr;
+extern bool no_fp, no_unreachable, retpoline, module, backtrace, uaccess, stats,
+            validate_dup, vmlinux, mcount, noinstr, backup;
+
+extern int cmd_parse_options(int argc, const char **argv, const char * const usage[]);
 
 extern int cmd_check(int argc, const char **argv);
 extern int cmd_orc(int argc, const char **argv);
diff --git a/tools/objtool/objtool.c b/tools/objtool/objtool.c
index 3a3ea1b4e4da..e21db8bce493 100644
--- a/tools/objtool/objtool.c
+++ b/tools/objtool/objtool.c
@@ -17,6 +17,7 @@
 #include <stdbool.h>
 #include <string.h>
 #include <stdlib.h>
+#include <unistd.h>
 #include <subcmd/exec-cmd.h>
 #include <subcmd/pager.h>
 #include <linux/kernel.h>
@@ -44,6 +45,64 @@ bool help;
 const char *objname;
 static struct objtool_file file;
 
+static bool objtool_create_backup(const char *_objname)
+{
+	int len = strlen(_objname);
+	char *buf, *base, *name = malloc(len+6);
+	int s, d, l, t;
+
+	if (!name) {
+		perror("failed backup name malloc");
+		return false;
+	}
+
+	strcpy(name, _objname);
+	strcpy(name + len, ".orig");
+
+	d = open(name, O_CREAT|O_WRONLY|O_TRUNC, 0644);
+	if (d < 0) {
+		perror("failed to create backup file");
+		return false;
+	}
+
+	s = open(_objname, O_RDONLY);
+	if (s < 0) {
+		perror("failed to open orig file");
+		return false;
+	}
+
+	buf = malloc(4096);
+	if (!buf) {
+		perror("failed backup data malloc");
+		return false;
+	}
+
+	while ((l = read(s, buf, 4096)) > 0) {
+		base = buf;
+		do {
+			t = write(d, base, l);
+			if (t < 0) {
+				perror("failed backup write");
+				return false;
+			}
+			base += t;
+			l -= t;
+		} while (l);
+	}
+
+	if (l < 0) {
+		perror("failed backup read");
+		return false;
+	}
+
+	free(name);
+	free(buf);
+	close(d);
+	close(s);
+
+	return true;
+}
+
 struct objtool_file *objtool_open_read(const char *_objname)
 {
 	if (objname) {
@@ -59,6 +118,11 @@ struct objtool_file *objtool_open_read(const char *_objname)
 	if (!file.elf)
 		return NULL;
 
+	if (backup && !objtool_create_backup(objname)) {
+		WARN("can't create backup file");
+		return NULL;
+	}
+
 	INIT_LIST_HEAD(&file.insn_list);
 	hash_init(file.insn_hash);
 	INIT_LIST_HEAD(&file.retpoline_call_list);