[PATCH] fix compilation of 64-bit kernel with 32-bit compiler

From: Mikulas Patocka
Date: Thu Mar 08 2018 - 01:11:35 EST


The patch b5bc2231b8ad4387c9641f235ca0ad8cd300b6df ("objtool: Add
retpoline validation") broke compiling 64-bit kernel with 32-bit compiler.

This patch fixes the following error and a large number of "can't find
rela for retpoline_safe" errors that occur when using x32 or i386 gcc.

You shouldn't use the type 'unsigned long' in objtool at all - because its
size depends on the compiler and not on the kernel you are compiling.

In file included from check.c:26:0:
check.c: In function 'read_retpoline_hints':
warn.h:57:3: error: format '%ld' expects argument of type 'long int', but argument 5 has type 'unsigned int' [-Werror=format=]
"%s: warning: objtool: " format "\n", \
^
check.c:1135:3: note: in expansion of macro 'WARN'
WARN("retpoline_safe size mismatch: %d %ld", sec->len, sizeof(unsigned long));
^~~~
check.c:1135:44: note: format string is defined here
WARN("retpoline_safe size mismatch: %d %ld", sec->len, sizeof(unsigned long));
~~^
%d

Signed-off-by: Mikulas Patocka <mpatocka@xxxxxxxxxx>
Fixes: b5bc2231b8ad ("objtool: Add retpoline validation")

---
tools/objtool/check.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)

Index: linux-2.6/tools/objtool/check.c
===================================================================
--- linux-2.6.orig/tools/objtool/check.c 2018-03-08 06:53:03.535471000 +0100
+++ linux-2.6/tools/objtool/check.c 2018-03-08 06:56:32.975471000 +0100
@@ -1131,13 +1131,13 @@ static int read_retpoline_hints(struct o
return -1;
}

- if (sec->len % sizeof(unsigned long)) {
- WARN("retpoline_safe size mismatch: %d %ld", sec->len, sizeof(unsigned long));
+ if (sec->len % sizeof(uint64_t)) {
+ WARN("retpoline_safe size mismatch: %d %d", sec->len, (int)sizeof(uint64_t));
return -1;
}

- for (i = 0; i < sec->len / sizeof(unsigned long); i++) {
- rela = find_rela_by_dest(sec, i * sizeof(unsigned long));
+ for (i = 0; i < sec->len / sizeof(uint64_t); i++) {
+ rela = find_rela_by_dest(sec, i * sizeof(uint64_t));
if (!rela) {
WARN("can't find rela for retpoline_safe[%d]", i);
return -1;