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=-1.1 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, 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 C457AC04AA7 for ; Mon, 13 May 2019 15:02:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 84F6820879 for ; Mon, 13 May 2019 15:02:04 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="p4xxK9Mt" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730837AbfEMPCD (ORCPT ); Mon, 13 May 2019 11:02:03 -0400 Received: from mail-pf1-f195.google.com ([209.85.210.195]:44689 "EHLO mail-pf1-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730098AbfEMPCD (ORCPT ); Mon, 13 May 2019 11:02:03 -0400 Received: by mail-pf1-f195.google.com with SMTP id g9so7343501pfo.11 for ; Mon, 13 May 2019 08:02:03 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc:content-transfer-encoding; bh=C7voGvIz1Mro50lqBnPKKj2CWBhaokOwzo7P+5YBsm8=; b=p4xxK9Mtx+xg5+k+hZu9ZBOfd0Sf1jrR3sIiWSG/lyTOQtD+Q8c/mSfXlpRX2UHFdx IWzvaZfGuFsrAnS7jAOduiso+wNQMqNnL1JHU9xHIHWl+r9+i3gq5FNFyD5lAtKkJ84J 6smJ66yf9FEYk0amnNLRgUH0DNsD1qapxtA3Uw6ONaMrJy3WvxAVUfOK5/Xu4fUsEgqC rB0bRzJeq+givqfupC5xMLgzkxhWs21s6FIvoDneGMyLyeDps0M8d6N40uUjanpgwFgo Kg6FTMpYwOEraKAnCnTzyh0Odeojfvqg0ytInx9P3zVTC8C5K8fvWWSAKnLyklmL5Hnq wuwg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc:content-transfer-encoding; bh=C7voGvIz1Mro50lqBnPKKj2CWBhaokOwzo7P+5YBsm8=; b=ZBvVS9Wb2L1xNeBTAZSVvm7ZS30d2YBOTR6lLiy+q31L8h6PeuFgXpWxfWABQFQ87/ jRp3mM+ad0xCL6pr6QjMfkqBODeY98+onfc9FeqoGVo6z12T8KQNh4O9MOkZlIgrVR1u bju/xWszAruvTFeHu+DuzBRU75bypxLCBktEB+k+aK8MUnk4ARD99UQf+Xew3O8QdHXh rpWs+tAj6y7JcAXVc8eXq7ms7bzOYh7Lr9QsHmTxF3cbkL23u9pUZiMkNaN6nhheVNo/ brN9yGhS37CzzvKj3ZLFj4+aHud8glvlboqlYv+oRhlFcvY1rhjPndgBxZHNTIfZ6S/O QXSg== X-Gm-Message-State: APjAAAXor1HDBQK9nJfTHSgQonQZOTMZd7XUmFaJbRDIGh9BX/B3T9qJ Fql+VJ2A56ZZcVOG6xUbQeg7B2ZQg+LWkpVdbfc= X-Google-Smtp-Source: APXvYqzp9FkkuUjdWmn0w1KnmfDMwzRBLLXx/D3EzBYNrlWhBjehcPBiILMqNMEjQjfhBB4PZXDGZJog/qYs8AhyIs4= X-Received: by 2002:a63:6988:: with SMTP id e130mr32026855pgc.150.1557759722780; Mon, 13 May 2019 08:02:02 -0700 (PDT) MIME-Version: 1.0 References: <1557676457-4195-1-git-send-email-akinobu.mita@gmail.com> <1557676457-4195-6-git-send-email-akinobu.mita@gmail.com> <20190513140246.GB24840@lst.de> In-Reply-To: <20190513140246.GB24840@lst.de> From: Akinobu Mita Date: Tue, 14 May 2019 00:01:51 +0900 Message-ID: Subject: Re: [PATCH v3 5/7] nvme-pci: add device coredump infrastructure To: Christoph Hellwig Cc: linux-nvme@lists.infradead.org, LKML , Johannes Berg , Keith Busch , Jens Axboe , Sagi Grimberg , Minwoo Im , Kenneth Heitke Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 2019=E5=B9=B45=E6=9C=8813=E6=97=A5(=E6=9C=88) 23:03 Christoph Hellwig : > > Usage of a scatterlist here is rather bogus as we never use > it for dma mapping. Why can't you store the various pages in a > large bio_vec and then just issue that to the device in one > get log page command? (or at least a few if MDTS kicks in?) OK. I'll try to use bio_vec and see how it goes.