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Date:   Mon, 24 Oct 2022 14:16:14 -0300
From:   Jason Gunthorpe <jgg@nvidia.com>
To:     Li Zhijian <lizhijian@fujitsu.com>
Cc:     zyjzyj2000@gmail.com, leon@kernel.org, linux-rdma@vger.kernel.org,
        linux-kernel@vger.kernel.org, Bob Pearson <rpearsonhpe@gmail.com>
Subject: Re: [PATCH for-next v3 1/2] RDMA/rxe: Remove unnecessary mr testing
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On Mon, Oct 24, 2022 at 03:31:54AM +0000, Li Zhijian wrote:
> Before the testing, we already passed it to rxe_mr_copy() where mr could
> be dereferenced. so this checking is not needed.
> 
> The only way that mr is NULL is when it reaches below line 780 with
>  'qp->resp.mr = NULL', which is not possible in Bob's explanation[1].
> 
>  778         if (res->state == rdatm_res_state_new) {
>  779                 if (!res->replay) {
>  780                         mr = qp->resp.mr;
>  781                         qp->resp.mr = NULL;
>  782                 } else {
> 
> [1] https://lore.kernel.org/lkml/30ff25c4-ce66-eac4-eaa2-64c0db203a19@gmail.com/
> 
> CC: Bob Pearson <rpearsonhpe@gmail.com>
> Signed-off-by: Li Zhijian <lizhijian@fujitsu.com>
> Reviewed-by: Bob Pearson <rpearsonhpe@gmail.com>
> ---
> V3: remove WARN_ON # Yanjun and Bob
> ---
>  drivers/infiniband/sw/rxe/rxe_resp.c | 3 +--
>  1 file changed, 1 insertion(+), 2 deletions(-)

Applied to for-next

Thanks,
Jason