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 13E28E810A2 for ; Wed, 27 Sep 2023 08:00:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230078AbjI0IAK (ORCPT ); Wed, 27 Sep 2023 04:00:10 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54692 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230081AbjI0IAF (ORCPT ); Wed, 27 Sep 2023 04:00:05 -0400 Received: from smtp-out2.suse.de (smtp-out2.suse.de [195.135.220.29]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9EC87199; Wed, 27 Sep 2023 01:00:01 -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 3188A1F8C4; Wed, 27 Sep 2023 08:00:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_rsa; t=1695801600; 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=YVNRHsJW7fxIPxX1otv++5oBWUMe5xuAPdK1iJf8KC8=; b=yqQ+sWh7IiBbT93CC8DmJVICOWpZ5i8ZWR5rGk8VAo1Fepqay+lF2t2glLXe4nueaSkgt4 u9RA1ctmgqroHgROpZ6fBEzHM2XbtvsEwOrdg5FDO7FNecGJuOs0aUAs6BkMwf2vZT0naU 57BE1ZZKPePUfFJLiMiM8XNOauiuIgI= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_ed25519; t=1695801600; 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=YVNRHsJW7fxIPxX1otv++5oBWUMe5xuAPdK1iJf8KC8=; b=LGr2tbFw1b9AVN9EsdnzZruuKyWWnGmNugeXOKBFn/zwqczS0pjkbzoOfcQCrC7VBM4IPg zdbDG0rlm7e44mBw== 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 9BE4713479; Wed, 27 Sep 2023 07:59:59 +0000 (UTC) Received: from dovecot-director2.suse.de ([192.168.254.65]) by imap2.suse-dmz.suse.de with ESMTPSA id jzEYI//gE2UvWQAAMHmgww (envelope-from ); Wed, 27 Sep 2023 07:59:59 +0000 Message-ID: Date: Wed, 27 Sep 2023 09:59:58 +0200 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [RFC PATCH v2 00/18] scsi: scsi_error: Introduce new error handle mechanism Content-Language: en-US To: Wenchao Hao , Mike Christie , Christoph Hellwig Cc: "James E . J . Bottomley" , "Martin K . Petersen" , linux-scsi@vger.kernel.org, linux-kernel@vger.kernel.org, louhongxiang@huawei.com, lixiaokeng@huawei.com References: <20230901094127.2010873-1-haowenchao2@huawei.com> <47bed3cb-f307-ec55-5c28-051687dab1ea@huawei.com> <06268327-cfed-f266-34a7-fda69411ef2a@huawei.com> From: Hannes Reinecke In-Reply-To: <06268327-cfed-f266-34a7-fda69411ef2a@huawei.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 9/26/23 14:57, Wenchao Hao wrote: > On 2023/9/26 1:54, Mike Christie wrote: >> On 9/25/23 10:07 AM, Wenchao Hao wrote: >>> On 2023/9/25 22:55, Christoph Hellwig wrote: >>>> Before we add another new error handling mechanism we need to fix the >>>> old one first.  Hannes' work on not passing the scsi_cmnd to the >>>> various >>>> reset handlers hasn't made a lot of progress in the last five years and >>>> we'll need to urgently fix that first before adding even more >>>> complexity. >>>> >>> I observed Hannes's patches posted about one year ago, it has not been >>> applied yet. I don't know if he is still working on it. >>> >>> My patches do not depend much on that work, I think the conflict can be >>> solved fast between two changes. >> >> I think we want to figure out Hannes's patches first. >> >> For a new EH design we will want to be able to do multiple TMFs in >> parallel >> on the same host/target right? >> > > It's not necessary to do multiple TMFs in parallel, it's ok to make sure > each TMFs do not affect each other. > > For example, we have two devices: 0:0:0:0 and 0:0:0:1 > > Both of them request device reset, they do not happened in parallel, but > would in serial. If 0:0:0:0 is performing device reset in progress, 0:0:0:1 > just wait 0:0:0:0 to finish. > Well, not quite. Any higher-order TMFs are serialized by virtue of SCSI-EH, but command aborts (which also devolve down to TMFs on certain drivers) do run in parallel, and there we will be requiring multiple TMFs. Cheers, Hannes -- Dr. Hannes Reinecke Kernel Storage Architect hare@suse.de +49 911 74053 688 SUSE Software Solutions GmbH, Maxfeldstr. 5, 90409 Nürnberg HRB 36809 (AG Nürnberg), Geschäftsführer: Ivo Totev, Andrew Myers, Andrew McDonald, Martje Boudien Moerman