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=-1.0 required=3.0 tests=DKIMWL_WL_MED,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS 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 5FF75C282CE for ; Fri, 5 Apr 2019 17:59:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 18E8D2146F for ; Fri, 5 Apr 2019 17:59:43 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=kernel-dk.20150623.gappssmtp.com header.i=@kernel-dk.20150623.gappssmtp.com header.b="HPQAw1kn" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731183AbfDER7m (ORCPT ); Fri, 5 Apr 2019 13:59:42 -0400 Received: from mail-it1-f194.google.com ([209.85.166.194]:54051 "EHLO mail-it1-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728683AbfDER7m (ORCPT ); Fri, 5 Apr 2019 13:59:42 -0400 Received: by mail-it1-f194.google.com with SMTP id y204so10835380itf.3 for ; Fri, 05 Apr 2019 10:59:41 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel-dk.20150623.gappssmtp.com; s=20150623; h=subject:to:cc:references:from:message-id:date:user-agent :mime-version:in-reply-to:content-language:content-transfer-encoding; bh=XDfJotbVMoiW5ope76ksKwkqSMr67TpKxT+aX1WjESw=; b=HPQAw1knA7FTaW7tFZNg7Visr0mVxGy+a/YM2Lta9ut9xYSAdAEk4y1QBYe1ywlB6c 3nMGhSHjGLRyUR9rTiGG69/n6QkC5bIM6FNgifvmgvNeeR8SmHpe98lDKwGRRgbyR3Ah jV/SeAvwA05jdeKdHFIoSgM+sqwju1mQ4/X6JXfOqFxPiEUKhvh8l3Ld40yWozkPofM7 MN9jVWzjM6brHHlzeGeJY3pl4cpXrAAdw1PVQY/dfWrMv/ia1RNKosATEYQs9WXOH7ef 9otVLizOZ9glWtfLIrrrO85+Pex/oC5aVO+MkA40d+cOBlURFvWapbdL1WcUbQAdTrJL lePw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:cc:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=XDfJotbVMoiW5ope76ksKwkqSMr67TpKxT+aX1WjESw=; b=R4nsd+cMwe0bm+A+VF+779cj3isPeTIuSoo+FgMDos1hnbrNBIGEex1tW+goorDisr xNiQUf0GTpWx6zj8utOCdkAmmIJyXfPu4yke3YvBHy98towl468kt14AN+OazGmoni7x hb6L17zrn4K0Oo6pAAJcWsBFlj2NzmJxUYR3RZzDIV1mEGgFyvIout0dyx92FcFAbq08 bkHMPeqoeUW75I61oUURJzMuMq735NTTaZiWCvqLvkCUaoUu6xsUBw2laSbMErrjwKim lT+YsLtbilIMjd5/gxHZERGjEURKqbgPdRR56h/Kp61KfSYxOKkIFSu8PrrFCG4lit1T BWNQ== X-Gm-Message-State: APjAAAVQ7zSNZLxiSAfYoVUL4QkPHx2MZG2aMwaJAE++g6FvjW5LGGa7 yZYLGWZQNt4c2nCcF42GBQcEXQ== X-Google-Smtp-Source: APXvYqw+icLdC7W6Gv/TCUBYCFaxSHMoBehkuM5omDrEad3PxF/yMUjvQ1/fqudmipRgY3seEAOhPA== X-Received: by 2002:a02:8c59:: with SMTP id j25mr10666919jal.4.1554487181571; Fri, 05 Apr 2019 10:59:41 -0700 (PDT) Received: from [192.168.1.158] ([216.160.245.98]) by smtp.gmail.com with ESMTPSA id l8sm1455959itl.26.2019.04.05.10.59.39 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Fri, 05 Apr 2019 10:59:39 -0700 (PDT) Subject: Re: [PATCH] block: Revert v5.0 blk_mq_request_issue_directly() changes To: Bart Van Assche , Christoph Hellwig Cc: linux-block@vger.kernel.org, Christoph Hellwig , Ming Lei , Jianchao Wang , Hannes Reinecke , Johannes Thumshirn , James Smart , Dongli Zhang , Laurence Oberman , stable@vger.kernel.org References: <20190404170843.83517-1-bvanassche@acm.org> <20190405060612.GA32144@lst.de> From: Jens Axboe Message-ID: <58149bc4-1ece-dd50-4bfb-4e55306bf870@kernel.dk> Date: Fri, 5 Apr 2019 11:59:38 -0600 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.6.1 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-block-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org On 4/5/19 8:00 AM, Bart Van Assche wrote: > On 4/4/19 11:06 PM, Christoph Hellwig wrote: >> On Thu, Apr 04, 2019 at 10:08:43AM -0700, Bart Van Assche wrote: >>> blk_mq_try_issue_directly() can return BLK_STS*_RESOURCE for requests that >>> have been queued. If that happens when blk_mq_try_issue_directly() is called >>> by the dm-mpath driver then dm-mpath will try to resubmit a request that is >>> already queued and a kernel crash follows. Since it is nontrivial to fix >>> blk_mq_request_issue_directly(), revert the blk_mq_request_issue_directly() >>> changes that went into kernel v5.0. >> >> And what are we going to do about 5.1+? > > Hi Christoph, > > This patch was developed and tested on my setup against Jens' for-next > branch. So this patch should apply fine on kernel v5.1-rc3. I'm inclined to apply the bundled up version. It applies with a bit of help and merges cleanly between the 5.1 and 5.2 branches. -- Jens Axboe