1 files changed, 43 insertions, 11 deletions

diff --git a/tools/objtool/check.c b/tools/objtool/check.c
index e128d1c71c30..5422543faff8 100644
--- a/tools/objtool/check.c
+++ b/tools/objtool/check.c
@@ -28,6 +28,8 @@
 #include <linux/hashtable.h>
 #include <linux/kernel.h>
 
+#define FAKE_JUMP_OFFSET -1
+
 struct alternative {
 	struct list_head list;
 	struct instruction *insn;
@@ -163,6 +165,8 @@ static int __dead_end_function(struct objtool_file *file, struct symbol *func,
 		"__reiserfs_panic",
 		"lbug_with_loc",
 		"fortify_panic",
+		"machine_real_restart",
+		"rewind_stack_do_exit",
 	};
 
 	if (func->bind == STB_WEAK)
@@ -498,7 +502,7 @@ static int add_jump_destinations(struct objtool_file *file)
 		    insn->type != INSN_JUMP_UNCONDITIONAL)
 			continue;
 
-		if (insn->ignore)
+		if (insn->ignore || insn->offset == FAKE_JUMP_OFFSET)
 			continue;
 
 		rela = find_rela_by_dest_range(insn->sec, insn->offset,
@@ -645,10 +649,10 @@ static int handle_group_alt(struct objtool_file *file,
 		clear_insn_state(&fake_jump->state);
 
 		fake_jump->sec = special_alt->new_sec;
-		fake_jump->offset = -1;
+		fake_jump->offset = FAKE_JUMP_OFFSET;
 		fake_jump->type = INSN_JUMP_UNCONDITIONAL;
 		fake_jump->jump_dest = list_next_entry(last_orig_insn, list);
-		fake_jump->ignore = true;
+		fake_jump->func = orig_insn->func;
 	}
 
 	if (!special_alt->new_len) {
@@ -812,7 +816,7 @@ static int add_switch_table(struct objtool_file *file, struct instruction *insn,
 	struct symbol *pfunc = insn->func->pfunc;
 	unsigned int prev_offset = 0;
 
-	list_for_each_entry_from(rela, &file->rodata->rela->rela_list, list) {
+	list_for_each_entry_from(rela, &table->rela_sec->rela_list, list) {
 		if (rela == next_table)
 			break;
 
@@ -902,6 +906,7 @@ static struct rela *find_switch_table(struct objtool_file *file,
 {
 	struct rela *text_rela, *rodata_rela;
 	struct instruction *orig_insn = insn;
+	struct section *rodata_sec;
 	unsigned long table_offset;
 
 	/*
@@ -929,10 +934,13 @@ static struct rela *find_switch_table(struct objtool_file *file,
 		/* look for a relocation which references .rodata */
 		text_rela = find_rela_by_dest_range(insn->sec, insn->offset,
 						    insn->len);
-		if (!text_rela || text_rela->sym != file->rodata->sym)
+		if (!text_rela || text_rela->sym->type != STT_SECTION ||
+		    !text_rela->sym->sec->rodata)
 			continue;
 
 		table_offset = text_rela->addend;
+		rodata_sec = text_rela->sym->sec;
+
 		if (text_rela->type == R_X86_64_PC32)
 			table_offset += 4;
 
@@ -940,10 +948,10 @@ static struct rela *find_switch_table(struct objtool_file *file,
 		 * Make sure the .rodata address isn't associated with a
 		 * symbol.  gcc jump tables are anonymous data.
 		 */
-		if (find_symbol_containing(file->rodata, table_offset))
+		if (find_symbol_containing(rodata_sec, table_offset))
 			continue;
 
-		rodata_rela = find_rela_by_dest(file->rodata, table_offset);
+		rodata_rela = find_rela_by_dest(rodata_sec, table_offset);
 		if (rodata_rela) {
 			/*
 			 * Use of RIP-relative switch jumps is quite rare, and
@@ -1028,7 +1036,7 @@ static int add_switch_table_alts(struct objtool_file *file)
 	struct symbol *func;
 	int ret;
 
-	if (!file->rodata || !file->rodata->rela)
+	if (!file->rodata)
 		return 0;
 
 	for_each_sec(file, sec) {
@@ -1173,10 +1181,33 @@ static int read_retpoline_hints(struct objtool_file *file)
 	return 0;
 }
 
+static void mark_rodata(struct objtool_file *file)
+{
+	struct section *sec;
+	bool found = false;
+
+	/*
+	 * This searches for the .rodata section or multiple .rodata.func_name
+	 * sections if -fdata-sections is being used. The .str.1.1 and .str.1.8
+	 * rodata sections are ignored as they don't contain jump tables.
+	 */
+	for_each_sec(file, sec) {
+		if (!strncmp(sec->name, ".rodata", 7) &&
+		    !strstr(sec->name, ".str1.")) {
+			sec->rodata = true;
+			found = true;
+		}
+	}
+
+	file->rodata = found;
+}
+
 static int decode_sections(struct objtool_file *file)
 {
 	int ret;
 
+	mark_rodata(file);
+
 	ret = decode_instructions(file);
 	if (ret)
 		return ret;
@@ -1779,7 +1810,8 @@ static int validate_branch(struct objtool_file *file, struct instruction *first,
 			return 1;
 		}
 
-		func = insn->func ? insn->func->pfunc : NULL;
+		if (insn->func)
+			func = insn->func->pfunc;
 
 		if (func && insn->ignore) {
 			WARN_FUNC("BUG: why am I validating an ignored function?",
@@ -2132,9 +2164,10 @@ static void cleanup(struct objtool_file *file)
 	elf_close(file->elf);
 }
 
+static struct objtool_file file;
+
 int check(const char *_objname, bool orc)
 {
-	struct objtool_file file;
 	int ret, warnings = 0;
 
 	objname = _objname;
@@ -2146,7 +2179,6 @@ int check(const char *_objname, bool orc)
 	INIT_LIST_HEAD(&file.insn_list);
 	hash_init(file.insn_hash);
 	file.whitelist = find_section_by_name(file.elf, ".discard.func_stack_frame_non_standard");
-	file.rodata = find_section_by_name(file.elf, ".rodata");
 	file.c_file = find_section_by_name(file.elf, ".comment");
 	file.ignore_unreachables = no_unreachable;
 	file.hints = false;