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 3AECAC001DE for ; Thu, 10 Aug 2023 19:54:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235314AbjHJTy5 convert rfc822-to-8bit (ORCPT ); Thu, 10 Aug 2023 15:54:57 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38442 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233618AbjHJTy4 (ORCPT ); Thu, 10 Aug 2023 15:54:56 -0400 Received: from lithops.sigma-star.at (lithops.sigma-star.at [195.201.40.130]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2C682273E; Thu, 10 Aug 2023 12:54:50 -0700 (PDT) Received: from localhost (localhost [127.0.0.1]) by lithops.sigma-star.at (Postfix) with ESMTP id 9F9A7622F562; Thu, 10 Aug 2023 21:54:47 +0200 (CEST) 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 Zau3YReFNhfe; Thu, 10 Aug 2023 21:54:47 +0200 (CEST) Received: from localhost (localhost [127.0.0.1]) by lithops.sigma-star.at (Postfix) with ESMTP id 02602622F56E; Thu, 10 Aug 2023 21:54:47 +0200 (CEST) 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 LCroLhpcM-fu; Thu, 10 Aug 2023 21:54:46 +0200 (CEST) Received: from lithops.sigma-star.at (lithops.sigma-star.at [195.201.40.130]) by lithops.sigma-star.at (Postfix) with ESMTP id CA9C5622F562; Thu, 10 Aug 2023 21:54:46 +0200 (CEST) Date: Thu, 10 Aug 2023 21:54:46 +0200 (CEST) From: Richard Weinberger To: Christoph Hellwig Cc: linux-mtd , Stephan Wurm , stable , Miquel Raynal , Vignesh Raghavendra , Oliver Neukum , Ali Akcaagac , Jamie Lenehan , James Bottomley , "Martin K. Petersen" , Ezequiel Garcia , linux-kernel , linux-scsi Message-ID: <164102534.5258032.1691697286622.JavaMail.zimbra@nod.at> In-Reply-To: References: <20230810160019.16977-1-richard@nod.at> <20230810160019.16977-2-richard@nod.at> <298860961.5257332.1691684136772.JavaMail.zimbra@nod.at> Subject: Re: [PATCH 1/7] ubi: block: Refactor sg list processing for highmem 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: block: Refactor sg list processing for highmem Thread-Index: 1KQDP1L0ZIhn5gNyfCrsrXqi59LrWA== Precedence: bulk List-ID: X-Mailing-List: linux-scsi@vger.kernel.org ----- Ursprüngliche Mail ----- > Von: "Christoph Hellwig" > An: "richard" > On Thu, Aug 10, 2023 at 06:15:36PM +0200, Richard Weinberger wrote: >> >> The followup patches in this series will switch to kmap_sg() >> >> and we can remove our own helper and the bounce buffer. >> > >> > Please just use kmap_local and avoid the bounce buffering. >> >> Patch 6 does this. > > But why add the bounce buffering first if you can avoid it from the > very beginning by just using kmap_local instead of adding a new > caller for the deprecate kmap_atomic? Because I want this fix also in all stable trees. kmap_local() is rather new. When back porting patch 1/7, bounce buffers and kmap_atomic() are needed anyway. By doing this in patch 1/7 I avoid backport troubles and keep the delta between upstream and stable trees minimal. Thanks, //richard