Re: [bug report] RDMA/rxe: Protect QP state with qp->state_lock

[Leon Romanovsky <leon@kernel.org>]

On Thu, May 04, 2023 at 10:28:59AM +0300, Dan Carpenter wrote:
> Hello Bob Pearson,
> 
> The patch f605f26ea196: "RDMA/rxe: Protect QP state with
> qp->state_lock" from Apr 4, 2023, leads to the following Smatch
> static checker warning:
> 
> 	drivers/infiniband/sw/rxe/rxe_qp.c:716 rxe_qp_to_attr()
> 	error: double unlocked '&qp->state_lock' (orig line 713)
> 
> drivers/infiniband/sw/rxe/rxe_qp.c
>     705         rxe_av_to_attr(&qp->pri_av, &attr->ah_attr);
>     706         rxe_av_to_attr(&qp->alt_av, &attr->alt_ah_attr);
>     707 
>     708         /* Applications that get this state typically spin on it.
>     709          * Yield the processor
>     710          */
>     711         spin_lock_bh(&qp->state_lock);
>     712         if (qp->attr.sq_draining) {
>     713                 spin_unlock_bh(&qp->state_lock);
>                              ^^^^^^
> Unlock
> 
>     714                 cond_resched();
>     715         }

Arguably, lines 708-716 should be deleted.

Thanks

> --> 716         spin_unlock_bh(&qp->state_lock);
>                      ^^^^^^
> Double unlock
> 
>     717 
>     718         return 0;
>     719 }
> 
> regards,
> dan carpenter