signals: move cred_guard_mutex from task_struct to signal_struct
authorKOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Wed, 27 Oct 2010 22:34:08 +0000 (15:34 -0700)
committerLinus Torvalds <torvalds@linux-foundation.org>
Thu, 28 Oct 2010 01:03:12 +0000 (18:03 -0700)
commit9b1bf12d5d51bca178dea21b04a0805e29d60cf1
tree902a2c0e5882a2152da59a589958d6426dc84643
parentb84011508360d6885a9d95a235ec77d56f133377
signals: move cred_guard_mutex from task_struct to signal_struct

Oleg Nesterov pointed out we have to prevent multiple-threads-inside-exec
itself and we can reuse ->cred_guard_mutex for it.  Yes, concurrent
execve() has no worth.

Let's move ->cred_guard_mutex from task_struct to signal_struct.  It
naturally prevent multiple-threads-inside-exec.

Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Roland McGrath <roland@redhat.com>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
fs/exec.c
fs/proc/base.c
include/linux/init_task.h
include/linux/sched.h
include/linux/tracehook.h
kernel/cred.c
kernel/fork.c
kernel/ptrace.c