Re: [PATCH rdma-rc] RDMA/cm: Fix missing RDMA_CM_EVENT_REJECTED event after receiving REJ message

[Leon Romanovsky <leon@kernel.org>]

On Mon, Apr 06, 2020 at 02:45:56PM -0300, Jason Gunthorpe wrote:
> On Mon, Apr 06, 2020 at 08:32:42PM +0300, Leon Romanovsky wrote:
> > From: Leon Romanovsky <leonro@mellanox.com>
> >
> > The cm_reset_to_idle() call before formatting event changed the CM_ID
> > state from IB_CM_REQ_RCVD to be IB_CM_IDLE. It caused to wrong value
> > of CM_REJ_MESSAGE_REJECTED field.
> >
> > The result of that was that rdma_reject() calls in the passive side
> > didn't generate RDMA_CM_EVENT_REJECTED event in the active side.
> >
> > Fixes: 81ddb41f876d ("RDMA/cm: Allow ib_send_cm_rej() to be done under lock")
> > Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
> >  drivers/infiniband/core/cm.c | 24 +++++++++++++-----------
> >  1 file changed, 13 insertions(+), 11 deletions(-)
> >
> > diff --git a/drivers/infiniband/core/cm.c b/drivers/infiniband/core/cm.c
> > index bbbfa77dbce7..06f8eeba423a 100644
> > +++ b/drivers/infiniband/core/cm.c
> > @@ -1843,11 +1843,9 @@ static void cm_format_mra(struct cm_mra_msg *mra_msg,
> >
> >  static void cm_format_rej(struct cm_rej_msg *rej_msg,
> >  			  struct cm_id_private *cm_id_priv,
> > -			  enum ib_cm_rej_reason reason,
> > -			  void *ari,
> > -			  u8 ari_length,
> > -			  const void *private_data,
> > -			  u8 private_data_len)
> > +			  enum ib_cm_rej_reason reason, void *ari,
> > +			  u8 ari_length, const void *private_data,
> > +			  u8 private_data_len, enum ib_cm_state state)
> >  {
> >  	lockdep_assert_held(&cm_id_priv->lock);
> >
> > @@ -1855,7 +1853,7 @@ static void cm_format_rej(struct cm_rej_msg *rej_msg,
> >  	IBA_SET(CM_REJ_REMOTE_COMM_ID, rej_msg,
> >  		be32_to_cpu(cm_id_priv->id.remote_id));
> >
> > -	switch(cm_id_priv->id.state) {
> > +	switch (state) {
> >  	case IB_CM_REQ_RCVD:
> >  		IBA_SET(CM_REJ_LOCAL_COMM_ID, rej_msg, be32_to_cpu(0));
> >  		IBA_SET(CM_REJ_MESSAGE_REJECTED, rej_msg, CM_MSG_RESPONSE_REQ);
> > @@ -1920,8 +1918,9 @@ static void cm_dup_req_handler(struct cm_work *work,
> >  			      cm_id_priv->private_data_len);
> >  		break;
> >  	case IB_CM_TIMEWAIT:
> > -		cm_format_rej((struct cm_rej_msg *) msg->mad, cm_id_priv,
> > -			      IB_CM_REJ_STALE_CONN, NULL, 0, NULL, 0);
> > +		cm_format_rej((struct cm_rej_msg *)msg->mad, cm_id_priv,
> > +			      IB_CM_REJ_STALE_CONN, NULL, 0, NULL, 0,
> > +			      cm_id_priv->id.state);
>
> This can just be IB_CM_TIMEWAIT instead of cm_id_priv->id.state

It can, do you want me to resend it? Or maybe you can change it while
applying?

Thanks

>
> Jason