kbuild: filter away debug symbols from kernel symbols

Andi Kleen <andi@firstfloor.org>
reported that he saw a lot of symbols like this:

0000000000000b24 N DW.aio.h.903a6d92.2
0000000000000bce N DW.task_io_accounting.h.8d8de327.0
0000000000000bec N DW.hrtimer.h.c23659c6.0

in his System.map / kallsyms output.

Simple solution is to skip all debugging
symbols (they are marked 'N').

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Cc: Paulo Marques <pmarques@grupopie.com>

2 files changed, 5 insertions, 1 deletions

diff --git a/scripts/kallsyms.c b/scripts/kallsyms.c
index 5d20a2e24cd..ad2434b2697 100644
--- a/scripts/kallsyms.c
+++ b/scripts/kallsyms.c
@@ -108,6 +108,9 @@ static int read_symbol(FILE *in, struct sym_entry *s)
         /* exclude also MIPS ELF local symbols ($L123 instead of .L123) */
         else if (str[0] == '$')
                 return -1;
+        /* exclude debugging symbols */
+        else if (stype == 'N')
+                return -1;
 
         /* include the type field in the symbol name, so that it gets
          * compressed together */
diff --git a/scripts/mksysmap b/scripts/mksysmap
index 4390fab9f5b..6e133a0bae7 100644
--- a/scripts/mksysmap
+++ b/scripts/mksysmap
@@ -32,6 +32,7 @@
 # For System.map filter away:
 #   a - local absolute symbols
 #   U - undefined global symbols
+#   N - debugging symbols
 #   w - local weak symbols
 
 # readprofile starts reading symbols when _stext is found, and
@@ -40,5 +41,5 @@
 # so we just ignore them to let readprofile continue to work.
 # (At least sparc64 has __crc_ in the middle).
 
-$NM -n $1 | grep -v '\( [aUw] \)\|\(__crc_\)\|\( \$[adt]\)' > $2
+$NM -n $1 | grep -v '\( [aNUw] \)\|\(__crc_\)\|\( \$[adt]\)' > $2