From: Oleg Nesterov <oleg@redhat.com>
Date: Mon, 7 Apr 2014 22:38:30 +0000 (-0700)
Subject: exit: move check_stack_usage() to the end of do_exit()
X-Git-Tag: v4.9.8~6596^2~73
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=4bcb8232cf4eb061b086c10f56b6808adcdb5a93;p=platform%2Fkernel%2Flinux-rpi3.git

exit: move check_stack_usage() to the end of do_exit()

It is not clear why check_stack_usage() is called so early and thus it
never checks the stack usage in, say, exit_notify() or
flush_ptrace_hw_breakpoint() or other functions which are only called by
do_exit().

Move the callsite down to the last preempt_disable/schedule.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---

diff --git a/kernel/exit.c b/kernel/exit.c
index 11f9e39..171c9a9d7 100644
--- a/kernel/exit.c
+++ b/kernel/exit.c
@@ -788,7 +788,6 @@ void do_exit(long code)
 		disassociate_ctty(1);
 	exit_task_namespaces(tsk);
 	exit_task_work(tsk);
-	check_stack_usage();
 	exit_thread();
 
 	/*
@@ -842,6 +841,7 @@ void do_exit(long code)
 
 	validate_creds_for_do_exit(tsk);
 
+	check_stack_usage();
 	preempt_disable();
 	if (tsk->nr_dirtied)
 		__this_cpu_add(dirty_throttle_leaks, tsk->nr_dirtied);