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 886CEC4332F for ; Thu, 10 Nov 2022 20:12:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230405AbiKJUMm convert rfc822-to-8bit (ORCPT ); Thu, 10 Nov 2022 15:12:42 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56104 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229461AbiKJUMh (ORCPT ); Thu, 10 Nov 2022 15:12:37 -0500 Received: from lithops.sigma-star.at (lithops.sigma-star.at [195.201.40.130]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1A2CD2F382; Thu, 10 Nov 2022 12:12:37 -0800 (PST) Received: from localhost (localhost [127.0.0.1]) by lithops.sigma-star.at (Postfix) with ESMTP id C40F863CDC5B; Thu, 10 Nov 2022 21:12:35 +0100 (CET) Received: from lithops.sigma-star.at ([127.0.0.1]) by localhost (lithops.sigma-star.at [127.0.0.1]) (amavisd-new, port 10032) with ESMTP id 8t93NELvwpPx; Thu, 10 Nov 2022 21:12:35 +0100 (CET) Received: from localhost (localhost [127.0.0.1]) by lithops.sigma-star.at (Postfix) with ESMTP id 632B161B8B4D; Thu, 10 Nov 2022 21:12:35 +0100 (CET) Received: from lithops.sigma-star.at ([127.0.0.1]) by localhost (lithops.sigma-star.at [127.0.0.1]) (amavisd-new, port 10026) with ESMTP id drrJ2Br71Io2; Thu, 10 Nov 2022 21:12:35 +0100 (CET) Received: from lithops.sigma-star.at (lithops.sigma-star.at [195.201.40.130]) by lithops.sigma-star.at (Postfix) with ESMTP id 3BA6463CDC5B; Thu, 10 Nov 2022 21:12:35 +0100 (CET) Date: Thu, 10 Nov 2022 21:12:35 +0100 (CET) From: Richard Weinberger To: Daniel Golle Cc: Jens Axboe , Miquel Raynal , Vignesh Raghavendra , Davidlohr Bueso , Matthew Wilcox , "Martin K. Petersen" , Chaitanya Kulkarni , Ming Lei , linux-block , linux-kernel , linux-mtd , linux-efi Message-ID: <871124728.219224.1668111155161.JavaMail.zimbra@nod.at> In-Reply-To: References: <1691046252.219046.1668109493753.JavaMail.zimbra@nod.at> Subject: Re: [PATCH v4 4/5] mtd_blkdevs: add option to enable scanning for partitions MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8BIT X-Originating-IP: [195.201.40.130] X-Mailer: Zimbra 8.8.12_GA_3807 (ZimbraWebClient - FF97 (Linux)/8.8.12_GA_3809) Thread-Topic: mtd_blkdevs: add option to enable scanning for partitions Thread-Index: JXERWtnlcCWgydDBA6DChmOXmJ0hxw== Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org ----- Ursprüngliche Mail ----- > On Thu, Nov 10, 2022 at 08:44:53PM +0100, Richard Weinberger wrote: >> ----- Ursprüngliche Mail ----- >> > Von: "Daniel Golle" >> > + >> > + if (!IS_ENABLED(CONFIG_MTD_BLOCK_PARTITIONS) || mtd_type_is_nand(new->mtd)) >> > + gd->flags |= GENHD_FL_NO_PART; >> >> I know that NAND should not get used with mtdblock because lack of wearleveling >> and >> in general too many writes. But what exactly is the rationale to deny part >> scanning for NAND? > > As UBI should be used on NAND, partition scanning should be enabled for > ubiblock devices to have uImage.FIT filesystem subimages mapped by the > partition parser. > > If not skipping partition scanning on NAND-backed mtdblock devices the > scanning itself will already trigger multiple warnings which now happen > every time when a NAND-backed mtdblock device is being opened since > commit 96a3295c ("mtdblock: warn if opened on NAND"). I see, you want to promote UBI. Makes sense. In case you do a v5 series, please add a comment to the code. Thanks, //richard