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 X-Spam-Level: X-Spam-Status: No, score=-15.2 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_2 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7D1F8C4338F for ; Mon, 26 Jul 2021 07:58:34 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 59A1A60F57 for ; Mon, 26 Jul 2021 07:58:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232316AbhGZHSE convert rfc822-to-8bit (ORCPT ); Mon, 26 Jul 2021 03:18:04 -0400 Received: from relay5-d.mail.gandi.net ([217.70.183.197]:38457 "EHLO relay5-d.mail.gandi.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232068AbhGZHSE (ORCPT ); Mon, 26 Jul 2021 03:18:04 -0400 Received: (Authenticated sender: miquel.raynal@bootlin.com) by relay5-d.mail.gandi.net (Postfix) with ESMTPSA id 3F4401C0003; Mon, 26 Jul 2021 07:58:30 +0000 (UTC) Date: Mon, 26 Jul 2021 09:58:29 +0200 From: Miquel Raynal To: Manivannan Sadhasivam Cc: Martin Kaiser , Dan Carpenter , Richard Weinberger , Vignesh Raghavendra , Boris Brezillon , Tudor Ambarus , linux-mtd@lists.infradead.org, kernel-janitors@vger.kernel.org Subject: Re: [PATCH] mtd: rawnand: Add a check in of_get_nand_secure_regions() Message-ID: <20210726095829.63af18b2@xps13> In-Reply-To: <20210724160308.GA62321@thinkpad> References: <20210715225045.66185-1-miquel.raynal@bootlin.com> <20210724142712.GA24036@martin-debian-1.paytec.ch> <20210724160308.GA62321@thinkpad> Organization: Bootlin X-Mailer: Claws Mail 3.17.7 (GTK+ 2.24.32; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8BIT Precedence: bulk List-ID: X-Mailing-List: kernel-janitors@vger.kernel.org Hi Mani, Manivannan Sadhasivam wrote on Sat, 24 Jul 2021 21:33:08 +0530: > On Sat, Jul 24, 2021 at 04:27:30PM +0200, Martin Kaiser wrote: > > Hi all, > > > > Thus wrote Miquel Raynal (miquel.raynal@bootlin.com): > > > > > On Thu, 2021-06-17 at 13:37:25 UTC, Dan Carpenter wrote: > > > > Check for whether of_property_count_elems_of_size() returns a negative > > > > error code. > > > > > > Fixes: 13b89768275d ("mtd: rawnand: Add support for secure regions in NAND memory") > > > > Signed-off-by: Dan Carpenter > > > > Reviewed-by: Manivannan Sadhasivam > > > > > Applied to https://git.kernel.org/pub/scm/linux/kernel/git/mtd/linux.git mtd/fixes, thanks. > > > > I'm running linux-next on an imx25 system with the following flash chip > > > > [ 1.997539] nand: device found, Manufacturer ID: 0x98, Chip ID: 0xaa > > [ 2.004134] nand: Toshiba NAND 256MiB 1,8V 8-bit > > [ 2.008917] nand: 256 MiB, SLC, erase size: 128 KiB, page size: 2048, OOB size: 128 > > > > The system is using the drivers/mtd/nand/raw/mxc_nand.c driver. > > > > Since this commit appeared in linux-next, mxc_nand's probe function fails > > with -EINVAL, taking this path > > > > mxcnd_probe > > nand_scan > > nand_scan_with_ids > > nand_scan_tail > > of_get_nand_secure_regions > > > > nr_elem = of_property_count_elems_of_size(dn, "secure-regions", sizeof(u64)); > > returns -EINVAL as there's no secure-regions property in my device tree. > > > > Doh! Sorry for missing this. > > > We should certainly handle negative error codes before we calculate > > chip->nr_secure_regions = nr_elem / 2 > > but a missing secure-regions property is a valid case and should not make > > the probe fail. > > > > Absolutely! > > > If the property exists, but the device-tree entry is incorrect > > and of_property_count_elems_of_size returns -ENODATA, we might print a > > warning and ignore the entry. > > > > Hmm, I think it is best to error out in this case as the user has got DT wrong. > > > What do you think? > > > > Since of_property_count_elems_of_size() returns -EINVAL if the length is not > a multiple of sizeof(u64), we can't just ignore -EINVAL. > > So I think we can just check for the existence of the property before invoking > of_get_nand_secure_regions(). Miquel, what do you think? Yes please add this check and we should be good. Thanks, Miquèl