[MIPS] Make get_frame_info() more robust

Now get_frame_info() wants to detect move sp instruction first. It
assumes that the save ra in the stack instruction can't happen
before allocating frame size space into the stack.

Signed-off-by: Franck Bui-Huu <vagabon.xyz@gmail.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

diff --git a/arch/mips/kernel/process.c b/arch/mips/kernel/process.c
index da332d707ce54b106cc462c6660193da09e7b502..309bfa4a1520bc95166b2350d5860565e42b838a 100644 (file)
--- a/arch/mips/kernel/process.c
+++ b/arch/mips/kernel/process.c
@@ -321,17 +321,15 @@ static int get_frame_info(struct mips_frame_info *info)
 
                if (is_jal_jalr_jr_ins(ip))
                        break;
-               if (is_sp_move_ins(ip)) {
-                       if (info->frame_size)
-                               continue;
-                       info->frame_size = - ip->i_format.simmediate;
+               if (!info->frame_size) {
+                       if (is_sp_move_ins(ip))
+                               info->frame_size = - ip->i_format.simmediate;
+                       continue;
                }
-
-               if (is_ra_save_ins(ip)) {
-                       if (info->pc_offset != -1)
-                               continue;
+               if (info->pc_offset == -1 && is_ra_save_ins(ip)) {
                        info->pc_offset =
                                ip->i_format.simmediate / sizeof(long);
+                       break;
                }
        }
        if (info->frame_size && info->pc_offset >= 0) /* nested */