From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pf0-f171.google.com (mail-pf0-f171.google.com [209.85.192.171]) by dpdk.org (Postfix) with ESMTP id 52A24ADA2 for ; Tue, 16 Feb 2016 02:32:42 +0100 (CET) Received: by mail-pf0-f171.google.com with SMTP id q63so95477797pfb.0 for ; Mon, 15 Feb 2016 17:32:42 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=igel-co-jp.20150623.gappssmtp.com; s=20150623; h=from:subject:to:references:cc:message-id:date:user-agent :mime-version:in-reply-to:content-type:content-transfer-encoding; bh=tFWqnvY7rZDqlMRAj2YYrt6Q8y7nLY6YXZpwmxwasx4=; b=NkaHnlm0Wviov2hAlyB6IsAm1ygAF4aDH1XfpL/ihfccU270Tpwo1hPbSfIKloJfDD WS/PBR8KqCyjppl181smAYH9QkxjiEQBIYLEuVo4/NnZ8i4zMk2EpGYmFy93mpUFjpOp EYv5BDkzgxF1FrKX6D8Bf51Ddg6upiBNUUAa6yhHcPjrEaz49QJOSJpVMSRYX4DZYpLF egh70RgkJi1cRkyc3rKU/p6UybAHWe09Zg3FT0V6b6egnwrVmFY835i7k+hkJsZw7V5P GEAaQuqq7sWxhWNLe3S+tvhPvAtD4INnXM156uYCcZpgRz26DbdSQHA1dNT/W9zi3ENj K2dw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:from:subject:to:references:cc:message-id:date :user-agent:mime-version:in-reply-to:content-type :content-transfer-encoding; bh=tFWqnvY7rZDqlMRAj2YYrt6Q8y7nLY6YXZpwmxwasx4=; b=cHAmauAgzIRMIp4OLmzgfYhdfq6TyzOxzr+9FL3fVlkgcQZieANo3Ga2mYpH9pqr4i WZY/Z13k/6Jvmvo9H8iuh+4RCVNLCHyJHW6jbpQQ5uFhGa1iv76zcbzK3m9RuNaoBUMg 1EdCPKo1jHhlJcpoLUFFLrbMk84nYQYFB9SVcLFlEhtkkCUzkfCD/BRh9iPubpJtzt73 meS4jKgL6/wvZ9BC28FWHpd5J2/2hNzSBC2/cdpixxSB+X0adHyIVlMOXixQUzeos06o x2tJxOB5+8wcNYfZfunKTQbhTzjfaZ5JUm1NyTCF5Efu7Z1V5Jp+G5BV+brU71LcI0uK pJZA== X-Gm-Message-State: AG10YORhB1dlrUmIYiQ4Lnx6oG6l/84vTo8mOIceiyxKB5TD3qNFJAFWBYBA4cbQsUVvsg== X-Received: by 10.98.93.205 with SMTP id n74mr3198286pfj.99.1455586361548; Mon, 15 Feb 2016 17:32:41 -0800 (PST) Received: from [10.16.129.101] (napt.igel.co.jp. [219.106.231.132]) by smtp.googlemail.com with ESMTPSA id 6sm41188359pfo.58.2016.02.15.17.32.39 (version=TLSv1/SSLv3 cipher=OTHER); Mon, 15 Feb 2016 17:32:40 -0800 (PST) From: Tetsuya Mukawa To: "Tan, Jianfeng" , dev@dpdk.org References: <1453374478-30996-6-git-send-email-mukawa@igel.co.jp> <1455075613-3605-3-git-send-email-mukawa@igel.co.jp> <56C183C4.4090105@intel.com> X-Enigmail-Draft-Status: N1110 Message-ID: <56C27C37.6020807@igel.co.jp> Date: Tue, 16 Feb 2016 10:32:39 +0900 User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:38.0) Gecko/20100101 Thunderbird/38.5.1 MIME-Version: 1.0 In-Reply-To: <56C183C4.4090105@intel.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Subject: Re: [dpdk-dev] [PATCH v2 2/5] EAL: Add new EAL "--qtest-virtio" option X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: patches and discussions about DPDK List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 16 Feb 2016 01:32:42 -0000 On 2016/02/15 16:52, Tan, Jianfeng wrote: > Hi Tetsuya, > > On 2/10/2016 11:40 AM, Tetsuya Mukawa wrote: >> To work with qtest virtio-net PMD, virtual address that maps hugepages >> should be between (1 << 31) to (1 << 44). This patch adds one more >> option > > Is there any reference about this limitation? And is it also true for > 32 bit machine? > Hi Jianfeng, 44bit limitation is come from virtio legacy device spec. The queue address register of virtio device is 32bit width. And we should set page number to this register. As a result, EAL memory should be under 44 bits. I only support virtio modern device with this patch series. So we can relax this limitation a bit. (Next limitation may be 47 bits. It seems it is come from QEMU implementation.) But I guess 44bit limitation is still not so hard, also we can leave a possibility to support legacy device. 31bits limitation is come from current memory mapping of QTest QEMU guest. Here is. * ------------------------------------------------------------ * Memory mapping of qtest quest * ------------------------------------------------------------ * 0x00000000_00000000 - 0x00000000_3fffffff : not used * 0x00000000_40000000 - 0x00000000_40000fff : virtio-net(BAR1) * 0x00000000_40001000 - 0x00000000_40ffffff : not used * 0x00000000_41000000 - 0x00000000_417fffff : virtio-net(BAR4) * 0x00000000_41800000 - 0x00000000_41ffffff : not used * 0x00000000_42000000 - 0x00000000_420000ff : ivshmem(BAR0) * 0x00000000_42000100 - 0x00000000_42ffffff : not used * 0x00000000_80000000 - 0xffffffff_ffffffff : ivshmem(BAR2) Thanks, Tetsuya > Thanks, > Jianfeng