Commit 6fa3c577 authored by Liang Zhen's avatar Liang Zhen Committed by Greg Kroah-Hartman
Browse files

staging/lustre/o2iblnd: connection refcount fix for kiblnd_post_rx 



kiblnd_post_rx() can't refer to rx::rx_conn anymore after
ib_post_recv() because this rx can be polled out by another thread
which may drop this rx and destroy rx::rx_conn.

This patch fixes this issue by taking an extra refcount on connection
before calling ib_post_recv().

Signed-off-by: default avatarLiang Zhen <liang.zhen@intel.com>
Reviewed-on: http://review.whamcloud.com/12852
Intel-bug-id: https://jira.hpdd.intel.com/browse/LU-5678


Reviewed-by: default avatarIsaac Huang <he.huang@intel.com>
Reviewed-by: default avatarAmir Shehata <amir.shehata@intel.com>
Signed-off-by: default avatarOleg Drokin <oleg.drokin@intel.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent bbaa9c10

drivers/staging/lustre/lnet/klnds/o2iblnd/o2iblnd_cb.c

+12 −6
Original line number Diff line number Diff line
@@ -178,24 +178,28 @@ kiblnd_post_rx(kib_rx_t *rx, int credit) 


	rx->rx_nob = -1;			/* flag posted */



	/* NB: need an extra reference after ib_post_recv because we don't

	 * own this rx (and rx::rx_conn) anymore, LU-5678.

	 */

	kiblnd_conn_addref(conn);

	rc = ib_post_recv(conn->ibc_cmid->qp, &rx->rx_wrq, &bad_wrq);

	if (rc != 0) {

	if (unlikely(rc != 0)) {

		CERROR("Can't post rx for %s: %d, bad_wrq: %p\n",

		       libcfs_nid2str(conn->ibc_peer->ibp_nid), rc, bad_wrq);

		rx->rx_nob = 0;

	}



	if (conn->ibc_state < IBLND_CONN_ESTABLISHED) /* Initial post */

		return rc;

		goto out;



	if (rc != 0) {

	if (unlikely(rc != 0)) {

		kiblnd_close_conn(conn, rc);

		kiblnd_drop_rx(rx);	     /* No more posts for this rx */

		return rc;

		goto out;

	}



	if (credit == IBLND_POSTRX_NO_CREDIT)

		return 0;

		goto out;



	spin_lock(&conn->ibc_lock);

	if (credit == IBLND_POSTRX_PEER_CREDIT)
@@ -205,7 +209,9 @@ kiblnd_post_rx(kib_rx_t *rx, int credit) 
	spin_unlock(&conn->ibc_lock);



	kiblnd_check_sends(conn);

	return 0;

out:

	kiblnd_conn_decref(conn);

	return rc;

}



static kib_tx_t *