From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 98F84C433FE for ; Mon, 31 Jan 2022 13:55:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1377880AbiAaNzJ (ORCPT ); Mon, 31 Jan 2022 08:55:09 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57230 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S243076AbiAaNzI (ORCPT ); Mon, 31 Jan 2022 08:55:08 -0500 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4C47AC061714; Mon, 31 Jan 2022 05:55:08 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id E15C7612C8; Mon, 31 Jan 2022 13:55:07 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id AA89BC340EE; Mon, 31 Jan 2022 13:55:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1643637307; bh=Mux+ePrY92AdNvLzvqVcgpb98PfbvNDN5o5jwmjyfww=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=bCGy+cUsKVh1qxUrE4zCpjye+OJAvX7e3cTfdxgTndfpBEZz+UwzMFXmJvXr5aiQy SuIxQWsSjykVcYiw59O41KScLb862vSFn98HsWXbJXsJ/ANaVb5/xO5xHN70SQkTBO DKPJmvLCJYfzgJOi58r2C58pLlptCOs8LolavgwUS+Lvkoclal/EzQKfPzIy+1ZYMz UzypcFTal4H9gH0YHh+Ha4n01PS8Gf3RLbj4GXhKIk8WyzROpPaxwWvdXeUA22zaQX 0km23LsI4JZX/OwphBxMAORiU4Y4RIHo2AUr0X1xiguTWQdycyIlkm/tlbHck8F6TY 0JRZ0yiXxWyDg== Date: Mon, 31 Jan 2022 13:55:00 +0000 From: Mark Brown To: Pratyush Yadav Cc: Tudor Ambarus , Michael Walle , Miquel Raynal , Takahiro Kuwano , linux-spi@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] spi: spi-mem: check if data buffers are on stack Message-ID: References: <20220131114508.1028306-1-p.yadav@ti.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="dgw4aAEj6xocjt/W" Content-Disposition: inline In-Reply-To: <20220131114508.1028306-1-p.yadav@ti.com> X-Cookie: I will never lie to you. Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --dgw4aAEj6xocjt/W Content-Type: text/plain; charset=us-ascii Content-Disposition: inline On Mon, Jan 31, 2022 at 05:15:08PM +0530, Pratyush Yadav wrote: > The buffers passed in the data phase must be DMA-able. Programmers often > don't realise this requirement and pass in buffers that reside on the > stack. This can be hard to spot when reviewing code. Reject ops if their > data buffer is on the stack to avoid this. Acked-by: Mark Brown > + /* Buffers must be DMA-able. */ > + if (op->data.dir == SPI_MEM_DATA_IN && > + object_is_on_stack(op->data.buf.in)) Might be worth a WARN_ON_ONCE() for debuggability? --dgw4aAEj6xocjt/W Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQEzBAABCgAdFiEEreZoqmdXGLWf4p/qJNaLcl1Uh9AFAmH36jMACgkQJNaLcl1U h9Do6Af+PYxmL6o8QTkbuSMNCf4zLsOLWsjug+Pzqn02yk4lNTbwV29h3+FEqewh trvMCVQgaMabgUOf/9hZhlYOJHod52b77dQI7iBolONua4wUPqHsNtO+p9FP7V46 gjUkTp54ArBKRRI8rlP/IpJy9ZAlzEEZEeXzGn/FZtw+Sdh8RDsFPSiB2X265XQG dYLDlWfbrKc/2rSAoi46iZY9J9lcm86V44LAdJ1GoLXUf/esHiOtLftGUA+9xGb+ MoOIrMhQ1+AtnAx6fdg0DwD6aKNBFT7gCVqUOvteLnFGGCYKTMSF1OAuywY+4CSj n1ri3jkVecHB15q9WpPtuVniim+7fA== =ywN3 -----END PGP SIGNATURE----- --dgw4aAEj6xocjt/W--