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=-10.7 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_PASS,USER_AGENT_NEOMUTT,USER_IN_DEF_DKIM_WL 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 D6954C0044C for ; Fri, 2 Nov 2018 00:12:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7A24A2081B for ; Fri, 2 Nov 2018 00:12:09 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=cisco.com header.i=@cisco.com header.b="V3ZnMaVS" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 7A24A2081B Authentication-Results: mail.kernel.org; dmarc=fail (p=quarantine dis=none) header.from=cisco.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728256AbeKBJRN (ORCPT ); Fri, 2 Nov 2018 05:17:13 -0400 Received: from alln-iport-4.cisco.com ([173.37.142.91]:40685 "EHLO alln-iport-4.cisco.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728058AbeKBJRN (ORCPT ); Fri, 2 Nov 2018 05:17:13 -0400 X-Greylist: delayed 563 seconds by postgrey-1.27 at vger.kernel.org; Fri, 02 Nov 2018 05:17:13 EDT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=cisco.com; i=@cisco.com; l=966; q=dns/txt; s=iport; t=1541117524; x=1542327124; h=date:from:to:cc:subject:message-id:references: mime-version:in-reply-to; bh=y0h06bDjERW54u9e3GFfoFZ7LBzd7gGim9w0oCA7N6A=; b=V3ZnMaVSSStnmLG97Kad7LJf73Wbub0LTuqsuMdflvQgRMYUmAerCl1S ICOb8Fd6z3CKP73aDunLcYL/42Db5sRu2SwZZURV8eWUzzBweeQLiiaQf Rh7Wr3eTlYNVB7I1B6Xi8g1RCyBWxzmzzugKGAeiAfy3byK7ij2lV9kLS 0=; X-IronPort-AV: E=Sophos;i="5.54,454,1534809600"; d="scan'208";a="195135796" Received: from alln-core-8.cisco.com ([173.36.13.141]) by alln-iport-4.cisco.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 02 Nov 2018 00:02:42 +0000 Received: from zorba ([10.24.121.150]) by alln-core-8.cisco.com (8.15.2/8.15.2) with ESMTPS id wA202dcg023096 (version=TLSv1.2 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=NO); Fri, 2 Nov 2018 00:02:41 GMT Date: Thu, 1 Nov 2018 17:02:36 -0700 From: Daniel Walker To: Nikunj Kela Cc: David Woodhouse , xe-linux-external@cisco.com, Rod Whitby , linux-mtd@lists.infradead.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] Make JFFS2 endianness configurable Message-ID: <20181102000236.rqho7txtb7gv543t@zorba> References: <20181101225603.17806-1-nkela@cisco.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20181101225603.17806-1-nkela@cisco.com> User-Agent: NeoMutt/20170609 (1.8.3) X-Auto-Response-Suppress: DR, OOF, AutoReply X-Outbound-SMTP-Client: 10.24.121.150, [10.24.121.150] X-Outbound-Node: alln-core-8.cisco.com Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Nov 01, 2018 at 03:56:03PM -0700, Nikunj Kela wrote: > This patch allows the endianness of the JFSS2 filesystem to be > specified by config options. > > It defaults to native-endian (the previously hard-coded option). > > Some architectures benefit from having a single known endianness > of JFFS2 filesystem (for data, not executables) independent of the > endianness of the processor (ARM processors can be switched to either > endianness at run-time). > The description is pretty sad .. We have a product which we released that uses JFFS2, and that product was release with a kernel in one endianness. Then later on we decided to change the endianness and now we're stuck with a JFFS2 partition that has the wrong endiannes, in a released product. This patch allows us to set the endianness to something different from the architecture setting. So there a significant use case for the change, at least for Cisco. Daniel