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=-17.5 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,NICE_REPLY_A, SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 AEDEBC47082 for ; Mon, 7 Jun 2021 05:46:33 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8386A610A2 for ; Mon, 7 Jun 2021 05:46:33 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230127AbhFGFsW (ORCPT ); Mon, 7 Jun 2021 01:48:22 -0400 Received: from fllv0015.ext.ti.com ([198.47.19.141]:49986 "EHLO fllv0015.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229436AbhFGFsV (ORCPT ); Mon, 7 Jun 2021 01:48:21 -0400 Received: from lelv0265.itg.ti.com ([10.180.67.224]) by fllv0015.ext.ti.com (8.15.2/8.15.2) with ESMTP id 1575kBLg005472; Mon, 7 Jun 2021 00:46:11 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ti.com; s=ti-com-17Q1; t=1623044771; bh=b3YribPsLsUNBcVX/uBU0uUtAjN0H/Dr6M1HW8UYZKg=; h=Subject:To:CC:References:From:Date:In-Reply-To; b=Rmu6KxldSL3T4RDaoN0NsYS+xvbdRRySK3B9EF9dwUXuFSLe7Wao3hpmkudAxDvXj QIj8bhXEUlL4q6ELOVBbrrGxsMOedRR/kGI60ALuLsqfqKD3KUUmGctEipKKN4UK2N q1QIJoKWuy56VwePeBFtsXY+0lIvl3U8TGepuEOA= Received: from DFLE105.ent.ti.com (dfle105.ent.ti.com [10.64.6.26]) by lelv0265.itg.ti.com (8.15.2/8.15.2) with ESMTPS id 1575kB1H106501 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=FAIL); Mon, 7 Jun 2021 00:46:11 -0500 Received: from DFLE110.ent.ti.com (10.64.6.31) by DFLE105.ent.ti.com (10.64.6.26) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.2176.2; Mon, 7 Jun 2021 00:46:11 -0500 Received: from fllv0039.itg.ti.com (10.64.41.19) by DFLE110.ent.ti.com (10.64.6.31) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.2176.2 via Frontend Transport; Mon, 7 Jun 2021 00:46:11 -0500 Received: from [10.250.234.148] (ileax41-snat.itg.ti.com [10.172.224.153]) by fllv0039.itg.ti.com (8.15.2/8.15.2) with ESMTP id 1575k8o2089338; Mon, 7 Jun 2021 00:46:09 -0500 Subject: Re: [PATCH v5 3/5] mtd: spi-nor: otp: return -EROFS if region is read-only To: Michael Walle , CC: , , , , References: <20210604100252.9975-1-michael@walle.cc> <20210604100252.9975-4-michael@walle.cc> From: Vignesh Raghavendra Message-ID: <1549db61-500a-e5df-9303-823b41457861@ti.com> Date: Mon, 7 Jun 2021 11:16:07 +0530 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.8.1 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset="utf-8" Content-Language: en-US Content-Transfer-Encoding: 8bit X-EXCLAIMER-MD-CONFIG: e1e8a2fd-e40a-4ac6-ac9b-f7e9cc9ee180 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 6/4/21 6:45 PM, Michael Walle wrote: > Am 2021-06-04 15:07, schrieb Tudor.Ambarus@microchip.com: >> On 6/4/21 1:02 PM, Michael Walle wrote: >>> EXTERNAL EMAIL: Do not click links or open attachments unless you >>> know the content is safe >>> >>> SPI NOR flashes will just ignore program commands if the OTP region is >>> locked. Thus, a user might not notice that the intended write didn't end >>> up in the flash. Return -EROFS to the user in this case. From what I can >>> tell, chips/cfi_cmdset_0001.c also return this error code. >>> >>> One could optimize spi_nor_mtd_otp_range_is_locked() to read the status >>> register only once and not for every OTP region, but for that we would >>> need some more invasive changes. Given that this is >>> one-time-programmable memory and the normal access mode is reading, we >>> just live with the small overhead. >>> >>> Fixes: 069089acf88b ("mtd: spi-nor: add OTP support") >>> Signed-off-by: Michael Walle >>> Reviewed-by: Pratyush Yadav >>> --- >>>  drivers/mtd/spi-nor/otp.c | 36 ++++++++++++++++++++++++++++++++++++ >>>  1 file changed, 36 insertions(+) >>> >>> diff --git a/drivers/mtd/spi-nor/otp.c b/drivers/mtd/spi-nor/otp.c >>> index 3898ed67ba1c..063f8fb68649 100644 >>> --- a/drivers/mtd/spi-nor/otp.c >>> +++ b/drivers/mtd/spi-nor/otp.c >>> @@ -249,6 +249,32 @@ static int spi_nor_mtd_otp_info(struct mtd_info >>> *mtd, size_t len, >>>         return ret; >>>  } >>> >>> +static int spi_nor_mtd_otp_range_is_locked(struct spi_nor *nor, >>> loff_t ofs, >>> +                                          size_t len) >>> +{ >>> +       const struct spi_nor_otp_ops *ops = nor->params->otp.ops; >>> +       unsigned int region; >>> +       int locked; >>> + >>> +       if (!len) >>> +               return 0; >>> + >> >> You won't need this if you put patch 4/5 before this one. With this: > > This patch will get backported to the stable kernels. Patch 4 on the > other hand does not. > I don't see why 4/5 cannot be marked for backport too as it makes 3/5 much cleaner? Regards Vignesh