Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
From:   David Laight <David.Laight@ACULAB.COM>
To:     'Arnd Bergmann' <arnd@kernel.org>,
        Bernard Metzler <bmt@zurich.ibm.com>,
        Jason Gunthorpe <jgg@ziepe.ca>,
        Leon Romanovsky <leon@kernel.org>,
        "Linus Walleij" <linus.walleij@linaro.org>
CC:     Arnd Bergmann <arnd@arndb.de>,
        "linux-rdma@vger.kernel.org" <linux-rdma@vger.kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: RE: [PATCH] RDMA/siw: fix pointer cast warning
Thread-Topic: [PATCH] RDMA/siw: fix pointer cast warning
Thread-Index: AQHZEKfEZmHYt+KmU0GxS8VCrAg8Pq5vhR6A
Date:   Thu, 15 Dec 2022 22:20:55 +0000
Message-ID: <1bba42a31e0a487bbbf67955b674583e@AcuMS.aculab.com>
References: <20221215170347.2612403-1-arnd@kernel.org>
In-Reply-To: <20221215170347.2612403-1-arnd@kernel.org>
Accept-Language: en-GB, en-US
MIME-Version: 1.0
Content-Language: en-US
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8BIT
Precedence: bulk

From: Arnd Bergmann
> Sent: 15 December 2022 17:04
> 
> From: Arnd Bergmann <arnd@arndb.de>
> 
> The previous build fix left a remaining issue in configurations
> with 64-bit dma_addr_t on 32-bit architectures:
> 
> drivers/infiniband/sw/siw/siw_qp_tx.c: In function 'siw_get_pblpage':
> drivers/infiniband/sw/siw/siw_qp_tx.c:32:37: error: cast to pointer from integer of different size [-
> Werror=int-to-pointer-cast]
>    32 |                 return virt_to_page((void *)paddr);
>       |                                     ^
> 
> Use the same double cast here that the driver uses elsewhere
> to convert between dma_addr_t and void*.
> 
> It took me a while to figure out why this driver does it
> like this, as there is no hardware access and it just stores
> kernel pointers in place of device addresses when communicating
> with the rdma core and with user space.

I hope that doesn't mean it is relying on user space only
giving it back valid values?

	David

-
Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK
Registration No: 1397386 (Wales)