[PATCH 4.9 10/30] objtool: Move objtool_file struct off the stack

[Greg Kroah-Hartman]

4.9-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Josh Poimboeuf <jpoimboe@xxxxxxxxxx>

commit 0c671812f152b628bd87c0af49da032cc2a2c319 upstream.

Objtool uses over 512k of stack, thanks to the hash table embedded in
the objtool_file struct.  This causes an unnecessarily large stack
allocation and breaks users with low stack limits.

Move the struct off the stack.

Fixes: 042ba73fe7eb ("objtool: Add several performance improvements")
Reported-by: Vassili Karpov <moosotc@xxxxxxxxx>
Signed-off-by: Josh Poimboeuf <jpoimboe@xxxxxxxxxx>
Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
Link: https://lkml.kernel.org/r/df92dcbc4b84b02ffa252f46876df125fb56e2d7.1552954176.git.jpoimboe@xxxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 tools/objtool/check.c |    3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

--- a/tools/objtool/check.c
+++ b/tools/objtool/check.c
@@ -2132,9 +2132,10 @@ static void cleanup(struct objtool_file
 	elf_close(file->elf);
 }
 
+static struct objtool_file file;
+
 int check(const char *_objname, bool orc)
 {
-	struct objtool_file file;
 	int ret, warnings = 0;
 
 	objname = _objname;