staging: lustre: avoid race during lnet acceptor thread termination

This patch will avoid potential race, around socket sleepers
wait list, during acceptor thread termination and using
sk_callback_lock RW-Lock protection.

Signed-off-by: Bruno Faccini <bruno.faccini@intel.com>
Intel-bug-id: https://jira.hpdd.intel.com/browse/LU-6476
Reviewed-on: http://review.whamcloud.com/14503
Reviewed-by: Amir Shehata <amir.shehata@intel.com>
Reviewed-by: John L. Hammond <john.hammond@intel.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/staging/lustre/lnet/lnet/acceptor.c b/drivers/staging/lustre/lnet/lnet/acceptor.c
index 8f9876bfb69237cab9129bba555dcb985217bab9..34684335e30c11db6d4146e37631a21e9f7c828c 100644 (file)
--- a/drivers/staging/lustre/lnet/lnet/acceptor.c
+++ b/drivers/staging/lustre/lnet/lnet/acceptor.c
@@ -488,11 +488,17 @@ lnet_acceptor_start(void)
 void
 lnet_acceptor_stop(void)
 {
+       struct sock *sk;
+
        if (lnet_acceptor_state.pta_shutdown) /* not running */
                return;
 
        lnet_acceptor_state.pta_shutdown = 1;
-       wake_up_all(sk_sleep(lnet_acceptor_state.pta_sock->sk));
+
+       sk = lnet_acceptor_state.pta_sock->sk;
+
+       /* awake any sleepers using safe method */
+       sk->sk_state_change(sk);
 
        /* block until acceptor signals exit */
        wait_for_completion(&lnet_acceptor_state.pta_signal);