diff options
author | Konstantin Khlebnikov <khlebnikov@openvz.org> | 2012-06-20 21:53:01 +0200 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2012-06-20 23:39:36 +0200 |
commit | 4fe7efdbdfb1c7e7a7f31decfd831c0f31d37091 (patch) | |
tree | 5d8fdf353ba3791ef10031ade2d93aa87aa179d3 /kernel/exit.c | |
parent | mm, thp: print useful information when mmap_sem is unlocked in zap_pmd_range (diff) | |
download | linux-4fe7efdbdfb1c7e7a7f31decfd831c0f31d37091.tar.xz linux-4fe7efdbdfb1c7e7a7f31decfd831c0f31d37091.zip |
mm: correctly synchronize rss-counters at exit/exec
do_exit() and exec_mmap() call sync_mm_rss() before mm_release() does
put_user(clear_child_tid) which can update task->rss_stat and thus make
mm->rss_stat inconsistent. This triggers the "BUG:" printk in check_mm().
Let's fix this bug in the safest way, and optimize/cleanup this later.
Reported-by: Markus Trippelsdorf <markus@trippelsdorf.de>
Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'kernel/exit.c')
-rw-r--r-- | kernel/exit.c | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/kernel/exit.c b/kernel/exit.c index 34867cc5b42a..c0277d3f1aaa 100644 --- a/kernel/exit.c +++ b/kernel/exit.c @@ -643,6 +643,7 @@ static void exit_mm(struct task_struct * tsk) mm_release(tsk, mm); if (!mm) return; + sync_mm_rss(mm); /* * Serialize with any possible pending coredump. * We must hold mmap_sem around checking core_state |