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 9DCF3C04E69 for ; Wed, 2 Aug 2023 11:03:54 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233962AbjHBLDx (ORCPT ); Wed, 2 Aug 2023 07:03:53 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39564 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232986AbjHBLDu (ORCPT ); Wed, 2 Aug 2023 07:03:50 -0400 Received: from smtp-out2.suse.de (smtp-out2.suse.de [195.135.220.29]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id EA8441FC3; Wed, 2 Aug 2023 04:03:48 -0700 (PDT) Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by smtp-out2.suse.de (Postfix) with ESMTPS id A28641F749; Wed, 2 Aug 2023 11:03:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_rsa; t=1690974227; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=7mCqh70c56B99LFYpEgpynueQhpFOzazSCA++MMtA2o=; b=tZ2ppa2kr4CLr5YWTwkasZluSsvIK4383Jj33YMEDmO0SUo3u4ch0Ukz7FvQbh3wD+up+x UlswJk23DOmx/uoEZlPcErxLVOMkcCvqUgDAYLganeTsb/3JHPv3K4Kl9dlgf1gOxjbX+2 bMsMYnFJ62qmI321xYoVufYY6g8lH+s= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_ed25519; t=1690974227; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=7mCqh70c56B99LFYpEgpynueQhpFOzazSCA++MMtA2o=; b=TbVUxGtNfbtW1NUuRUNAyJJI9DdYT7xovBxNQgz+b7Dffdw/Zz0QoouqI47kHIk/mLJwzy kQBNXfBz3Xv1jYBg== Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by imap2.suse-dmz.suse.de (Postfix) with ESMTPS id 8BB4D13919; Wed, 2 Aug 2023 11:03:47 +0000 (UTC) Received: from dovecot-director2.suse.de ([192.168.254.65]) by imap2.suse-dmz.suse.de with ESMTPSA id FMeuIRM4ymQfGwAAMHmgww (envelope-from ); Wed, 02 Aug 2023 11:03:47 +0000 Message-ID: <3f36882c-b429-3ece-989b-a6899c001cbd@suse.de> Date: Wed, 2 Aug 2023 13:03:47 +0200 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: XFS metadata CRC errors on zram block device on ppc64le architecture Content-Language: en-US To: wq@lst.de, Dusty Mabe Cc: Minchan Kim , Sergey Senozhatsky , Jens Axboe , linux-kernel@vger.kernel.org, linux-block@vger.kernel.org, Christoph Hellwig , Andrew Morton , marmijo@redhat.com References: <20230802094106.GA28187@lst.de> From: Hannes Reinecke In-Reply-To: <20230802094106.GA28187@lst.de> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 8/2/23 11:41, Christoph Hellwig wrote: > On Tue, Aug 01, 2023 at 11:31:37PM -0400, Dusty Mabe wrote: >> We ran a kernel bisect and narrowed it down to offending commit af8b04c6: >> >> ``` >> [root@ibm-p8-kvm-03-guest-02 linux]# git bisect good >> af8b04c63708fa730c0257084fab91fb2a9cecc4 is the first bad commit >> commit af8b04c63708fa730c0257084fab91fb2a9cecc4 >> Author: Christoph Hellwig >> Date: Tue Apr 11 19:14:46 2023 +0200 >> >> zram: simplify bvec iteration in __zram_make_request >> >> bio_for_each_segment synthetize bvecs that never cross page boundaries, so >> don't duplicate that work in an inner loop. > >> Any ideas on how to fix the problem? > > So the interesting cases are: > > - ppc64 usually uses 64k page sizes > - ppc64 is somewhat cache incoherent (compared to say x86) > > Let me think of this a bit more. Would need to be confirmed first that 64k pages really are in use (eg we compile ppc64le with 4k page sizes ...). Dusty? For which page size did you compile your kernel? Cheers, Hannes