diff options
| author | Tetsuo Handa | 2010-03-05 13:42:56 -0800 |
|---|---|---|
| committer | Linus Torvalds | 2010-03-06 11:26:33 -0800 |
| commit | 9728e5d6e6c432ee8487c63ce6e479e2474d9945 (patch) | |
| tree | 2cd7e9a9102649a36d52cbac918f045dcfaa08f2 /kernel/futex.c | |
| parent | 8aeee85a29e27e043db582bf2ae8e5f42767934f (diff) | |
kernel/pid.c: update comment on find_task_by_pid_ns
tasklist_lock does protect the task and its pid, it can't go away. The
problem is that find_pid_ns() itself is unsafe without rcu lock, it can
race with copy_process()->free_pid(any_pid).
Protecting copy_process()->free_pid(any_pid) with tasklist_lock would make
it possible to call find_task_by_pid_ns() under tasklist safely, but we
don't do so because we are trying to get rid of the read_lock sites of
tasklist_lock.
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: "Paul E. McKenney" <paulmck@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'kernel/futex.c')
0 files changed, 0 insertions, 0 deletions