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=-2.6 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,MAILING_LIST_MULTI,SPF_PASS,USER_AGENT_MUTT autolearn=unavailable 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 945BAC10F05 for ; Wed, 27 Mar 2019 02:32:46 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6380A20811 for ; Wed, 27 Mar 2019 02:32:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1553653966; bh=38CsVGEYGwjTvocJDUQvOsZSVyRYDE4Ydm1/Ydy5uaY=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=x4Tgpmb2sNOt/qyxISVEUcbxBSiO9DlAzfeqigmdbJMz+0Rj6ElM96p1qvsAQgCLU 2DysiOM3g1NIEmf2VNqKs9pqVvhTJir/0OzJB7QKlfuybfWswT8KL++5q7lMlp5own MukkooD+tJgtzPJ/bEA33TG+ZMniaGCYEzAGSvJY= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732559AbfC0Ccp (ORCPT ); Tue, 26 Mar 2019 22:32:45 -0400 Received: from mga04.intel.com ([192.55.52.120]:2191 "EHLO mga04.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730333AbfC0Cco (ORCPT ); Tue, 26 Mar 2019 22:32:44 -0400 X-Amp-Result: UNKNOWN X-Amp-Original-Verdict: FILE UNKNOWN X-Amp-File-Uploaded: False Received: from fmsmga008.fm.intel.com ([10.253.24.58]) by fmsmga104.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 26 Mar 2019 19:32:44 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.60,274,1549958400"; d="scan'208";a="135096858" Received: from unknown (HELO localhost.localdomain) ([10.232.112.69]) by fmsmga008.fm.intel.com with ESMTP; 26 Mar 2019 19:32:43 -0700 Date: Tue, 26 Mar 2019 20:33:54 -0600 From: Keith Busch To: "jianchao.wang" Cc: Jens Axboe , "Busch, Keith" , James Smart , Bart Van Assche , Ming Lei , Josef Bacik , linux-nvme , Linux Kernel Mailing List , linux-block , Hannes Reinecke , Johannes Thumshirn , Christoph Hellwig , Sagi Grimberg Subject: Re: [PATCH V2 7/8] nvme: use blk_mq_queue_tag_inflight_iter Message-ID: <20190327023354.GB7389@localhost.localdomain> References: <1553492318-1810-1-git-send-email-jianchao.w.wang@oracle.com> <1553492318-1810-8-git-send-email-jianchao.w.wang@oracle.com> <20190325134917.GA4328@localhost.localdomain> <70e14e12-2ffc-37db-dd8f-229bc580546e@oracle.com> <20190326235726.GC4328@localhost.localdomain> <20190327021521.GA7389@localhost.localdomain> <1bbe1b5c-3564-55e8-6824-f679b3c5dd3f@oracle.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1bbe1b5c-3564-55e8-6824-f679b3c5dd3f@oracle.com> User-Agent: Mutt/1.9.1 (2017-09-22) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Mar 27, 2019 at 10:27:57AM +0800, jianchao.wang wrote: > As the comment above, the stable request maybe something that has been freed due to following case, > 1. a hctx->fq.flush_rq of dead request_queue that shares the same tagset > 2. a removed io scheduler's sched request > and this freed request could be allocated by others which may change the field of request->state. You're not explaing how that request->state is changed. I understand the request can be reallocated, but what is changing its state?