objtool/arm64: Port klp-build to arm64

index b3801f532b10..b63887a1b823 100644
@@ -24,6 +24,7 @@
 #include <linux/nospec.h>
 #include <linux/prctl.h>
 #include <linux/sched/task_stack.h>
+#include <linux/annotate.h>
 
 #include <asm/debug-monitors.h>
 #include <asm/insn.h>

@@ -245,11 +246,12 @@ static noinstr void qcom_link_stack_sanitisation(void)
 {
 	u64 tmp;
 
-	asm volatile("mov	%0, x30		\n"
-		     ".rept	16		\n"
-		     "bl	. + 4		\n"
-		     ".endr			\n"
-		     "mov	x30, %0		\n"
+	asm volatile("mov	%0, x30			\n"
+		     ".rept	16			\n"
+		     ANNOTATE_INTRA_FUNCTION_CALL "	\n"
+		     "bl	. + 4			\n"
+		     ".endr				\n"
+		     "mov	x30, %0			\n"
 		     : "=&r" (tmp));
 }
 

index 1e1580febe4b..f82f170a97eb 100644
@@ -663,7 +663,7 @@
 		__static_call_text_end = .;
 
 /* Section used for early init (in .S files) */
-#define HEAD_TEXT  KEEP(*(.head.text))
+#define HEAD_TEXT  KEEP(*(.head.data .head.text))
 
 #define HEAD_TEXT_SECTION							\
 	.head.text : AT(ADDR(.head.text) - LOAD_OFFSET) {		\

index 40331923b9f4..91e16f3205e2 100644
@@ -90,6 +90,7 @@
 
 /* For assembly routines */
 #define __HEAD		.section	".head.text","ax"
+#define __HEADDATA	.section	".head.data","aw"
 #define __INIT		.section	".init.text","ax"
 #define __FINIT		.previous
 

index 2301fb7ff3c8..d428d63b29c6 100644
@@ -2633,8 +2633,7 @@ static bool validate_branch_enabled(void)
 {
 	return opts.stackval ||
 	       opts.orc ||
-	       opts.uaccess ||
-	       opts.checksum;
+	       opts.uaccess;
 }
 
 static int decode_sections(struct objtool_file *file)

@@ -3663,6 +3662,7 @@ static bool skip_alt_group(struct instruction *insn)
 	return alt_insn->type == INSN_CLAC || alt_insn->type == INSN_STAC;
 }
 
+#ifdef BUILD_KLP
 static int checksum_debug_init(struct objtool_file *file)
 {
 	char *dup, *s;

@@ -3705,9 +3705,30 @@ static void checksum_update_insn(struct objtool_file *file, struct symbol *func,
 				 struct instruction *insn)
 {
 	struct reloc *reloc = insn_reloc(file, insn);
+	struct alternative *alt;
 	unsigned long offset;
 	struct symbol *sym;
 
+	for (alt = insn->alts; alt; alt = alt->next) {
+		struct alt_group *alt_group = alt->insn->alt_group;
+
+		checksum_update(func, insn, &alt->type, sizeof(alt->type));
+
+		if (alt_group && alt_group->orig_group) {
+			struct instruction *alt_insn;
+
+			checksum_update(func, insn, &alt_group->feature, sizeof(alt_group->feature));
+
+			for (alt_insn = alt->insn; alt_insn; alt_insn = next_insn_same_sec(file, alt_insn)) {
+				checksum_update_insn(file, func, alt_insn);
+				if (alt_insn == alt_group->last_insn)
+					break;
+			}
+		} else {
+			checksum_update(func, insn, &alt->insn->offset, sizeof(alt->insn->offset));
+		}
+	}
+
 	if (insn->fake)
 		return;
 

@@ -3716,9 +3737,11 @@ static void checksum_update_insn(struct objtool_file *file, struct symbol *func,
 	if (!reloc) {
 		struct symbol *call_dest = insn_call_dest(insn);
 
-		if (call_dest)
+		if (call_dest) {
+			/* intra-TU call without reloc */
 			checksum_update(func, insn, call_dest->demangled_name,
 					strlen(call_dest->demangled_name));
+		}
 		return;
 	}
 

@@ -3745,6 +3768,29 @@ static void checksum_update_insn(struct objtool_file *file, struct symbol *func,
 	checksum_update(func, insn, &offset, sizeof(offset));
 }
 
+static int calculate_checksums(struct objtool_file *file)
+{
+	struct instruction *insn;
+	struct symbol *func;
+
+	if (checksum_debug_init(file))
+		return -1;
+
+	for_each_sym(file->elf, func) {
+		if (!is_func_sym(func))
+			continue;
+
+		checksum_init(func);
+
+		func_for_each_insn(file, func, insn)
+			checksum_update_insn(file, func, insn);
+
+		checksum_finish(func);
+	}
+	return 0;
+}
+#endif /* BUILD_KLP */
+
 static int validate_branch(struct objtool_file *file, struct symbol *func,
 			   struct instruction *insn, struct insn_state state);
 static int do_validate_branch(struct objtool_file *file, struct symbol *func,

@@ -4026,9 +4072,6 @@ static int do_validate_branch(struct objtool_file *file, struct symbol *func,
 		insn->trace = 0;
 		next_insn = next_insn_to_validate(file, insn);
 
-		if (opts.checksum && func && insn->sec)
-			checksum_update_insn(file, func, insn);
-
 		if (func && insn_func(insn) && func != insn_func(insn)->pfunc) {
 			/* Ignore KCFI type preambles, which always fall through */
 			if (is_prefix_func(func))

@@ -4094,9 +4137,6 @@ static int validate_unwind_hint(struct objtool_file *file,
 		struct symbol *func = insn_func(insn);
 		int ret;
 
-		if (opts.checksum)
-			checksum_init(func);
-
 		ret = validate_branch(file, func, insn, *state);
 		if (ret)
 			BT_INSN(insn, "<=== (hint)");

@@ -4539,9 +4579,6 @@ static int validate_symbol(struct objtool_file *file, struct section *sec,
 
 	func = insn_func(insn);
 
-	if (opts.checksum)
-		checksum_init(func);
-
 	if (opts.trace && !fnmatch(opts.trace, sym->name, 0)) {
 		trace_enable();
 		TRACE("%s: validation begin\n", sym->name);

@@ -4554,9 +4591,6 @@ static int validate_symbol(struct objtool_file *file, struct section *sec,
 	TRACE("%s: validation %s\n\n", sym->name, ret ? "failed" : "end");
 	trace_disable();
 
-	if (opts.checksum)
-		checksum_finish(func);
-
 	return ret;
 }
 

@@ -5011,10 +5045,6 @@ int check(struct objtool_file *file)
 	cfi_hash_add(&init_cfi);
 	cfi_hash_add(&func_cfi);
 
-	ret = checksum_debug_init(file);
-	if (ret)
-		goto out;
-
 	ret = decode_sections(file);
 	if (ret)
 		goto out;

@@ -5105,6 +5135,9 @@ int check(struct objtool_file *file)
 		warnings += check_abs_references(file);
 
 	if (opts.checksum) {
+		ret = calculate_checksums(file);
+		if (ret)
+			goto out;
 		ret = create_sym_checksum_section(file);
 		if (ret)
 			goto out;

index 7fe21608722a..36a17688c716 100644
@@ -32,11 +32,7 @@ static inline void checksum_finish(struct symbol *func)
 
 #else /* !BUILD_KLP */
 
-static inline void checksum_init(struct symbol *func) {}
-static inline void checksum_update(struct symbol *func,
-				   struct instruction *insn,
-				   const void *data, size_t size) {}
-static inline void checksum_finish(struct symbol *func) {}
+static inline int calculate_checksums(struct objtool_file *file) { return -ENOSYS; }
 
 #endif /* !BUILD_KLP */
 

index b780df513715..f528a58aca74 100644
@@ -145,11 +145,6 @@ int cmd_parse_options(int argc, const char **argv, const char * const usage[])
 
 static bool opts_valid(void)
 {
-	if (opts.mnop && !opts.mcount) {
-		ERROR("--mnop requires --mcount");
-		return false;
-	}
-
 	if (opts.noinstr && !opts.link) {
 		ERROR("--noinstr requires --link");
 		return false;

index d428d63b29c6..6e33a29bd3ed 100644
@@ -1630,10 +1630,12 @@ static int add_jump_destinations(struct objtool_file *file)
 			/*
 			 * GCOV/KCOV dead code can jump to the end of
 			 * the function/section.
+			 *
+			 * Clang on arm64 also does this sometimes for
+			 * undefined behavior.
 			 */
-			if (file->ignore_unreachables && func &&
-			    dest_sec == insn->sec &&
-			    dest_off == func->offset + func->len)
+			if ((file->ignore_unreachables || (!opts.stackval && !opts.orc)) &&
+			    func && dest_sec == insn->sec && dest_off == func->offset + func->len)
 				continue;
 
 			ERROR_INSN(insn, "can't find jump dest instruction at %s",

index 6e33a29bd3ed..7297fb87f876 100644
@@ -1994,10 +1994,8 @@ static int add_special_section_alts(struct objtool_file *file)
 		}
 
 		if (special_alt->group) {
-			if (!special_alt->orig_len) {
-				ERROR_INSN(orig_insn, "empty alternative entry");
+			if (!special_alt->orig_len)
 				continue;
-			}
 
 			if (handle_group_alt(file, special_alt, orig_insn, &new_insn))
 				return -1;

index b911abe3a15e..5ccae2c937dc 100644
@@ -1374,6 +1374,8 @@ struct elf *elf_create_file(GElf_Ehdr *ehdr, const char *name)
 
 unsigned int elf_add_string(struct elf *elf, struct section *strtab, const char *str)
 {
+	static unsigned int last_off;
+	static const char *last_str;
 	unsigned int offset;
 
 	if (!strtab)

@@ -1382,17 +1384,22 @@ unsigned int elf_add_string(struct elf *elf, struct section *strtab, const char
 		ERROR("can't find .strtab section");
 		return -1;
 	}
-
 	if (!strtab->sh.sh_addralign) {
 		ERROR("'%s': invalid sh_addralign", strtab->name);
 		return -1;
 	}
 
+	if (last_str && !strcmp(last_str, str))
+		return last_off;
+
 	offset = ALIGN(sec_size(strtab), strtab->sh.sh_addralign);
 
 	if (!elf_add_data(elf, strtab, str, strlen(str) + 1))
 		return -1;
 
+	last_str = str;
+	last_off = offset;
+
 	return offset;
 }
 

116 lines not on this page · raw message

new file mode 100644
index 000000000000..49c81cbb6646
@@ -0,0 +1,11 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+#ifndef _OBJTOOL_ARCH_CFI_REGS_H
+#define _OBJTOOL_ARCH_CFI_REGS_H
+
+/* These aren't actually used for arm64 */
+#define CFI_BP 0
+#define CFI_SP 0
+#define CFI_RA 0
+#define CFI_NUM_REGS 2
+
+#endif /* _OBJTOOL_ARCH_CFI_REGS_H */

new file mode 100644
index 000000000000..80a1bc479930
@@ -0,0 +1,13 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+#ifndef _OBJTOOL_ARCH_ELF_H
+#define _OBJTOOL_ARCH_ELF_H
+
+#define R_NONE		R_AARCH64_NONE
+#define R_ABS64		R_AARCH64_ABS64
+#define R_ABS32		R_AARCH64_ABS32
+#define R_DATA32	R_AARCH64_PREL32
+#define R_DATA64	R_AARCH64_PREL64
+#define R_TEXT32	R_AARCH64_PREL32
+#define R_TEXT64	R_AARCH64_PREL64
+
+#endif /* _OBJTOOL_ARCH_ELF_H */

new file mode 100644
index 000000000000..8ae804a83ea4
@@ -0,0 +1,21 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+#ifndef _OBJTOOL_ARCH_SPECIAL_H
+#define _OBJTOOL_ARCH_SPECIAL_H
+
+#define EX_ENTRY_SIZE 12
+#define EX_ORIG_OFFSET 0
+#define EX_NEW_OFFSET 4
+
+#define JUMP_ENTRY_SIZE 16
+#define JUMP_ORIG_OFFSET 0
+#define JUMP_NEW_OFFSET 4
+#define JUMP_KEY_OFFSET 8
+
+#define ALT_ENTRY_SIZE 12
+#define ALT_ORIG_OFFSET 0
+#define ALT_NEW_OFFSET 4
+#define ALT_FEATURE_OFFSET 8
+#define ALT_ORIG_LEN_OFFSET 10
+#define ALT_NEW_LEN_OFFSET 11
+
+#endif /* _OBJTOOL_ARCH_SPECIAL_H */

new file mode 100644
index 000000000000..3c2b83d94939
@@ -0,0 +1,21 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+#include <objtool/special.h>
+
+bool arch_support_alt_relocation(struct special_alt *special_alt,
+				 struct instruction *insn,
+				 struct reloc *reloc)
+{
+	return false;
+}
+
+struct reloc *arch_find_switch_table(struct objtool_file *file,
+				     struct instruction *insn,
+				     unsigned long *table_size)
+{
+	return NULL;
+}
+
+const char *arch_cpu_feature_name(int feature_number)
+{
+	return NULL;
+}