[PATCH 1/2] scripts/recordmcount.pl: support data in text section on powerpc

Michael Ellerman mpe at ellerman.id.au
Tue Jan 12 23:14:22 AEDT 2016

From: Ulrich Weigand <ulrich.weigand at de.ibm.com>

If a text section starts out with a data blob before the first
function start label, disassembly parsing doing in recordmcount.pl
gets confused on powerpc, leading to creation of corrupted module

This was not a problem so far since the compiler would never create
such text sections.  However, this has changed with a recent change
in GCC 6 to support distances of > 2GB between a function and its
assoicated TOC in the ELFv2 ABI, exposing this problem.

There is already code in recordmcount.pl to handle such data blobs
on the sparc64 platform.  This patch uses the same method to handle
those on powerpc as well.

Cc: stable at vger.kernel.org
Signed-off-by: Ulrich Weigand <ulrich.weigand at de.ibm.com>
Signed-off-by: Michael Ellerman <mpe at ellerman.id.au>
 scripts/recordmcount.pl | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

Steve can we get an ack for this one, to go via powerpc? cheers

diff --git a/scripts/recordmcount.pl b/scripts/recordmcount.pl
index 826470d7f000..96e2486a6fc4 100755
--- a/scripts/recordmcount.pl
+++ b/scripts/recordmcount.pl
@@ -263,7 +263,8 @@ if ($arch eq "x86_64") {
 } elsif ($arch eq "powerpc") {
     $local_regex = "^[0-9a-fA-F]+\\s+t\\s+(\\.?\\S+)";
-    $function_regex = "^([0-9a-fA-F]+)\\s+<(\\.?.*?)>:";
+    # See comment in the sparc64 section for why we use '\w'.
+    $function_regex = "^([0-9a-fA-F]+)\\s+<(\\.?\\w*?)>:";
     $mcount_regex = "^\\s*([0-9a-fA-F]+):.*\\s\\.?_mcount\$";
     if ($bits == 64) {

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