[tip:x86/pti] objtool: Don't print '.tmp_' prefix for .o files when CONFIG_MODVERSIONS=y

[tip-bot for Josh Poimboeuf]

Commit-ID:  dfcb8dae5d28b7cf259b367ed9ccbc1296284e0d
Gitweb:     https://git.kernel.org/tip/dfcb8dae5d28b7cf259b367ed9ccbc1296284e0d
Author:     Josh Poimboeuf <jpoimboe@xxxxxxxxxx>
AuthorDate: Mon, 29 Jan 2018 22:00:42 -0600
Committer:  Ingo Molnar <mingo@xxxxxxxxxx>
CommitDate: Tue, 30 Jan 2018 07:55:05 +0100

objtool: Don't print '.tmp_' prefix for .o files when CONFIG_MODVERSIONS=y

With the following commit:

  2a0098d70640 ("objtool: Fix seg fault with gold linker")

... objtool warnings started showing the modversions '.tmp_' prefix in
the .o file name, like:

  arch/x86/mm/.tmp_mem_encrypt_boot.o: warning: objtool: sme_encrypt_execute()+0x48: indirect call found in RETPOLINE build

The prefix is confusing.  Remove it from the printed 'objname' variable.

Signed-off-by: Josh Poimboeuf <jpoimboe@xxxxxxxxxx>
Cc: Andy Lutomirski <luto@xxxxxxxxxx>
Cc: Borislav Petkov <bp@xxxxxxxxx>
Cc: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx>
Cc: David Woodhouse <dwmw2@xxxxxxxxxxxxx>
Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Cc: Guenter Roeck <linux@xxxxxxxxxxxx>
Cc: H. Peter Anvin <hpa@xxxxxxxxx>
Cc: Juergen Gross <jgross@xxxxxxxx>
Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Fixes: 2a0098d70640 ("objtool: Fix seg fault with gold linker")
Link: http://lkml.kernel.org/r/3788b5aec1c279184b78cdbd8b520903c0fb8a80.1517284349.git.jpoimboe@xxxxxxxxxx
Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
---
 tools/objtool/check.c | 21 +++++++++++++++++++++
 1 file changed, 21 insertions(+)

diff --git a/tools/objtool/check.c b/tools/objtool/check.c
index 9cd028a..d45ab4d 100644
--- a/tools/objtool/check.c
+++ b/tools/objtool/check.c
@@ -1978,6 +1978,25 @@ static void cleanup(struct objtool_file *file)
 	elf_close(file->elf);
 }
 
+/*
+ * With CONFIG_MODVERSIONS=y, the object name has '.tmp_' prepended to it.
+ * After the file has been opened, remove the prefix so warnings will look
+ * sensible.
+ */
+static void fix_objname(void)
+{
+	char *s;
+
+	s = strstr(objname, ".tmp_");
+	if (!s)
+		return;
+
+	for (; s[5]; s++)
+		s[0] = s[5];
+
+	s[0] = 0;
+}
+
 int check(const char *_objname, bool _no_fp, bool no_unreachable, bool orc)
 {
 	struct objtool_file file;
@@ -1990,6 +2009,8 @@ int check(const char *_objname, bool _no_fp, bool no_unreachable, bool orc)
 	if (!file.elf)
 		return 1;
 
+	fix_objname();
+
 	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");