iw_cxgb4: fix srqidx leak during connection abort

When an application aborts the connection by moving QP from RTS to ERROR,
then iw_cxgb4's modify_rc_qp() RTS->ERROR logic sets the
*srqidxp to 0 via t4_set_wq_in_error(&qhp->wq, 0), and aborts the
connection by calling c4iw_ep_disconnect().

c4iw_ep_disconnect() does the following:
 1. sends up a close_complete_upcall(ep, -ECONNRESET) to libcxgb4.
 2. sends abort request CPL to hw.

But, since the close_complete_upcall() is sent before sending the
ABORT_REQ to hw, libcxgb4 would fail to release the srqidx if the
connection holds one. Because, the srqidx is passed up to libcxgb4 only
after corresponding ABORT_RPL is processed by kernel in abort_rpl().

This patch handle the corner-case by moving the call to
close_complete_upcall() from c4iw_ep_disconnect() to abort_rpl().  So that
libcxgb4 is notified about the -ECONNRESET only after abort_rpl(), and
libcxgb4 can relinquish the srqidx properly.

Signed-off-by: Raju Rangoju <rajur@chelsio.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

1 files changed, 3 insertions, 2 deletions

diff --git a/drivers/infiniband/hw/cxgb4/cm.c b/drivers/infiniband/hw/cxgb4/cm.c
index b188d89674f1..ae90b2932bd2 100644
--- a/drivers/infiniband/hw/cxgb4/cm.c
+++ b/drivers/infiniband/hw/cxgb4/cm.c
@@ -1941,8 +1941,10 @@ static int abort_rpl(struct c4iw_dev *dev, struct sk_buff *skb)
         }
         mutex_unlock(&ep->com.mutex);
 
-        if (release)
+        if (release) {
+                close_complete_upcall(ep, -ECONNRESET);
                 release_ep_resources(ep);
+        }
         c4iw_put_ep(&ep->com);
         return 0;
 }
@@ -3684,7 +3686,6 @@ int c4iw_ep_disconnect(struct c4iw_ep *ep, int abrupt, gfp_t gfp)
         if (close) {
                 if (abrupt) {
                         set_bit(EP_DISC_ABORT, &ep->com.history);
-                        close_complete_upcall(ep, -ECONNRESET);
                         ret = send_abort(ep);
                 } else {
                         set_bit(EP_DISC_CLOSE, &ep->com.history);