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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id C1F04C4332F for ; Mon, 18 Oct 2021 12:39:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A988D60EE9 for ; Mon, 18 Oct 2021 12:39:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231217AbhJRMlK (ORCPT ); Mon, 18 Oct 2021 08:41:10 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51002 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231803AbhJRMlE (ORCPT ); Mon, 18 Oct 2021 08:41:04 -0400 Received: from mail-il1-x12d.google.com (mail-il1-x12d.google.com [IPv6:2607:f8b0:4864:20::12d]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 93AF5C06176D for ; Mon, 18 Oct 2021 05:38:53 -0700 (PDT) Received: by mail-il1-x12d.google.com with SMTP id k3so14712526ilu.2 for ; Mon, 18 Oct 2021 05:38:53 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel-dk.20210112.gappssmtp.com; s=20210112; h=subject:to:cc:references:from:message-id:date:user-agent :mime-version:in-reply-to:content-language:content-transfer-encoding; bh=BcvXSYMKkxOdDPvUtRzou8KqQzfYeQv0RToRcKEVNAg=; b=btv+qo0CHuKzzErInGsQ65G06PcsWmsYaNtpYrofOdTvjw7QV8IRQV5i5mSRvG54Mi APy/xWafBG+suitucirc09YUL3kLNJ+JPmgiZzsigcDf+B2aoVILRnhCZ6IAsILxi9vt eSShdO+ySnGSmn4a/AI5t2cdbRFBDB0pS641bmqPOmXD7VkgfB3d9opYzoBEEsl4oEg8 LOTevcB3g3WlIbNqgmd2HdnsSXvN2JGvW79DBY+ErDphGsI+zADy5alEKkZRCdgwR4uq cxPmusTS3/Z70gytou6JjktWz1dWNk96uVZvKj70V073broLkNBgW3zLo/trd7ZS7Oid nnHA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; 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=BcvXSYMKkxOdDPvUtRzou8KqQzfYeQv0RToRcKEVNAg=; b=iOniFZLe3EvkAFs3L/UINnKeWxREG31l8fJCdd9PndbAQWnsGIixzN+0iaUHKX88rl AC6U8hcgMC72o5c6+uAQKIxs2EVEXodT/1siAAwzzbV3qICTAUZoGsqmcFl9NzFfEU8I wWMgikyxa9XXWZN2Gzix8KzpUVQaqwhlE7TxEnM2vuya50X2It4/i9kqkI0QtBMD8HBe zK9wTGSTCdWHT1GDjHcjjp2WN37n5qyKGXHegT0LgQfHsHzszAafH5WunwyBlrazrxeR xoduieeubzbtyFDEyUIYoXIgvQXbdQPjWapueyL1htFm9Rz6FAwV73iQnlXq6SyyZ5Ce HD0w== X-Gm-Message-State: AOAM533wRaihOSR/HO/LiCEsqnxhamoY+Kohmp78vJmQyHHaMU9BbguY tUxgx/itoKPRn+54X1ZKbSHsdQ== X-Google-Smtp-Source: ABdhPJyuTjdqdlTi1vGe3/gXFjBQ2qMMfEdb1Nmoo0MdFvLDvYbM17wlnmNOHqUXJjZQvwv9pPvX0A== X-Received: by 2002:a05:6e02:20c3:: with SMTP id 3mr13115359ilq.206.1634560733032; Mon, 18 Oct 2021 05:38:53 -0700 (PDT) Received: from [192.168.1.116] ([66.219.217.159]) by smtp.gmail.com with ESMTPSA id u12sm6742945ioc.33.2021.10.18.05.38.52 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Mon, 18 Oct 2021 05:38:52 -0700 (PDT) Subject: Re: [PATCH] nvme: don't memset() the normal read/write command To: Christoph Hellwig Cc: "linux-block@vger.kernel.org" , Keith Busch References: <20211013045822.GA24761@lst.de> <843b8695-9af7-ec33-da83-e711850223b1@kernel.dk> <20211018123750.GA17785@lst.de> From: Jens Axboe Message-ID: <4a5715e6-af4a-341c-906a-e5b5aa4e9d9a@kernel.dk> Date: Mon, 18 Oct 2021 06:38:51 -0600 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.10.0 MIME-Version: 1.0 In-Reply-To: <20211018123750.GA17785@lst.de> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org On 10/18/21 6:37 AM, Christoph Hellwig wrote: > On Mon, Oct 18, 2021 at 06:33:51AM -0600, Jens Axboe wrote: >>>> cmnd->rw.nsid = cpu_to_le32(ns->head->ns_id); >>>> + cmnd->rw.rsvd2 = 0; >>> >>> There should be no need to clear this reserved space. >> >> Actually wasn't sure, sometimes hardware specs required reserved fields >> to get cleared. nvme does not? I'd be happy to drop it if not the case. > > It only requires bits in otherwise unused fields to be the zeroed. > > That being said, yes we're probably on the safe side by clearing > everything. I'll keep the reserved clearing. -- Jens Axboe