Re: [PATCH] 9p/rdma: unmap receive dma buffer in rdma_request()

[Leon Romanovsky <leon@kernel.org>]

On Tue, Dec 20, 2022 at 11:12:23AM +0800, Zhengchao Shao wrote:
> When down_interruptible() failed in rdma_request(), receive dma buffer
> is not unmapped. Add unmap action to error path.
> 
> Fixes: fc79d4b104f0 ("9p: rdma: RDMA Transport Support for 9P")
> Signed-off-by: Zhengchao Shao <shaozhengchao@huawei.com>
> ---
>  net/9p/trans_rdma.c | 2 ++
>  1 file changed, 2 insertions(+)
> 
> diff --git a/net/9p/trans_rdma.c b/net/9p/trans_rdma.c
> index 83f9100d46bf..da83023fecbf 100644
> --- a/net/9p/trans_rdma.c
> +++ b/net/9p/trans_rdma.c
> @@ -499,6 +499,8 @@ static int rdma_request(struct p9_client *client, struct p9_req_t *req)
>  
>  	if (down_interruptible(&rdma->sq_sem)) {
>  		err = -EINTR;
> +		ib_dma_unmap_single(rdma->cm_id->device, c->busa,
> +				    c->req->tc.size, DMA_TO_DEVICE);
>  		goto send_error;
>  	}

It is not the only place where ib_dma_unmap_single() wasn't called.
Even at the same function if ib_post_send() fails, the unmap is not
called. Also post_recv() is missing call to ib_dma_unmap_single() too.

Thanks

>  
> -- 
> 2.34.1
>