[GIT pull] core updates for 4.13

From: Thomas Gleixner
Date: Sun Jul 09 2017 - 04:45:07 EST


Linus,

please pull the latest core-urgent-for-linus git tree from:

git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git core-urgent-for-linus

A fix to the objtool sibling call detection logic to distinguish normal
jumps inside a function from a real sibling call.

Thanks,

tglx

------------------>
Josh Poimboeuf (1):
objtool: Fix sibling call detection logic


tools/objtool/check.c | 13 +++++++++++--
1 file changed, 11 insertions(+), 2 deletions(-)

diff --git a/tools/objtool/check.c b/tools/objtool/check.c
index fea222192c57..2c6d74880403 100644
--- a/tools/objtool/check.c
+++ b/tools/objtool/check.c
@@ -1371,6 +1371,12 @@ static int validate_branch(struct objtool_file *file, struct instruction *first,

func = insn->func;

+ if (func && insn->ignore) {
+ WARN_FUNC("BUG: why am I validating an ignored function?",
+ sec, insn->offset);
+ return -1;
+ }
+
if (insn->visited) {
if (!!insn_state_match(insn, &state))
return 1;
@@ -1426,16 +1432,19 @@ static int validate_branch(struct objtool_file *file, struct instruction *first,

case INSN_JUMP_CONDITIONAL:
case INSN_JUMP_UNCONDITIONAL:
- if (insn->jump_dest) {
+ if (insn->jump_dest &&
+ (!func || !insn->jump_dest->func ||
+ func == insn->jump_dest->func)) {
ret = validate_branch(file, insn->jump_dest,
state);
if (ret)
return 1;
+
} else if (func && has_modified_stack_frame(&state)) {
WARN_FUNC("sibling call from callable instruction with modified stack frame",
sec, insn->offset);
return 1;
- } /* else it's a sibling call */
+ }

if (insn->type == INSN_JUMP_UNCONDITIONAL)
return 0;