Merge branch 'x86/debug' into core/urgent

Pick up the two pending objtool patches as the next round of objtool fixes
depend on them.

1 files changed, 20 insertions, 7 deletions

diff --git a/tools/objtool/check.c b/tools/objtool/check.c
index de8f40730b37..2f8ba0368231 100644
--- a/tools/objtool/check.c
+++ b/tools/objtool/check.c
@@ -18,6 +18,8 @@
 
 #define FAKE_JUMP_OFFSET -1
 
+#define C_JUMP_TABLE_SECTION ".rodata..c_jump_table"
+
 struct alternative {
 	struct list_head list;
 	struct instruction *insn;
@@ -1035,9 +1037,15 @@ 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.
+		 * symbol.  GCC jump tables are anonymous data.
+		 *
+		 * Also support C jump tables which are in the same format as
+		 * switch jump tables.  For objtool to recognize them, they
+		 * need to be placed in the C_JUMP_TABLE_SECTION section.  They
+		 * have symbols associated with them.
 		 */
-		if (find_symbol_containing(rodata_sec, table_offset))
+		if (find_symbol_containing(rodata_sec, table_offset) &&
+		    strcmp(rodata_sec->name, C_JUMP_TABLE_SECTION))
 			continue;
 
 		rodata_rela = find_rela_by_dest(rodata_sec, table_offset);
@@ -1277,13 +1285,18 @@ static void mark_rodata(struct objtool_file *file)
 	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.
+	 * Search for the following rodata sections, each of which can
+	 * potentially contain jump tables:
+	 *
+	 * - .rodata: can contain GCC switch tables
+	 * - .rodata.<func>: same, if -fdata-sections is being used
+	 * - .rodata..c_jump_table: contains C annotated jump tables
+	 *
+	 * .rodata.str1.* sections are ignored; they don't contain jump tables.
 	 */
 	for_each_sec(file, sec) {
-		if (!strncmp(sec->name, ".rodata", 7) &&
-		    !strstr(sec->name, ".str1.")) {
+		if ((!strncmp(sec->name, ".rodata", 7) && !strstr(sec->name, ".str1.")) ||
+		    !strcmp(sec->name, C_JUMP_TABLE_SECTION)) {
 			sec->rodata = true;
 			found = true;
 		}