From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tetsuya Mukawa Subject: Re: [PATCH v4 0/2] Add VHOST PMD Date: Thu, 19 Nov 2015 10:20:48 +0900 Message-ID: <564D23F0.1090100@igel.co.jp> References: <1447046221-20811-3-git-send-email-mukawa@igel.co.jp> <1447392031-24970-1-git-send-email-mukawa@igel.co.jp> <20151113053215.GN2326@yliu-dev.sh.intel.com> <56458828.7070009@igel.co.jp> <20151117132636.GU2326@yliu-dev.sh.intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Cc: dev@dpdk.org, ann.zhuangyanying@huawei.com To: Yuanhan Liu Return-path: Received: from mail-pa0-f47.google.com (mail-pa0-f47.google.com [209.85.220.47]) by dpdk.org (Postfix) with ESMTP id 8C6168D96 for ; Thu, 19 Nov 2015 02:20:52 +0100 (CET) Received: by padhx2 with SMTP id hx2so62387885pad.1 for ; Wed, 18 Nov 2015 17:20:52 -0800 (PST) In-Reply-To: <20151117132636.GU2326@yliu-dev.sh.intel.com> List-Id: patches and discussions about DPDK List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org Sender: "dev" On 2015/11/17 22:26, Yuanhan Liu wrote: > On Fri, Nov 13, 2015 at 03:50:16PM +0900, Tetsuya Mukawa wrote: >> On 2015/11/13 14:32, Yuanhan Liu wrote: >>> On Fri, Nov 13, 2015 at 02:20:29PM +0900, Tetsuya Mukawa wrote: >>>> The patch introduces a new PMD. This PMD is implemented as thin wrapper >>>> of librte_vhost. >>>> >>>> * Known issue. >>>> We may see issues while handling RESET_OWNER message. >>>> These handlings are done in vhost library, so not a part of vhost PMD. >>>> So far, we are waiting for QEMU fixing. >>> Fix patches have already been applied. Please help test :) >>> >>> --yliu >> Hi Yuanhan, >> >> It seems there might be an another issue related with "vq->callfd" in >> vhost library. >> We may miss something to handle the value correctly. >> >> Anyway, here are steps. >> 1. Apply vhost PMD patch. >> (I guess you don't need it to reproduce the issue, but to reproduce it, >> using the PMD may be easy) >> 2. Start testpmd on host with vhost-user PMD. >> 3. Start QEMU with virtio-net device. >> 4. Login QEMU. >> 5. Bind the virtio-net device to igb_uio. >> 6. Start testpmd in QEMU. >> 7. Quit testmd in QEMU. >> 8. Start testpmd again in QEMU. >> >> It seems when last command is executed, testpmd on host doesn't receive >> SET_VRING_CALL message from QEMU. >> Because of this, testpmd on host assumes virtio-net device is not ready. >> (I made sure virtio_is_ready() was failed on host). >> >> According to QEMU source code, SET_VRING_KICK will be called when >> virtqueue starts, but SET_VRING_CALL will be called when virtqueue is >> initialized. >> Not sure exactly, might be "vq->call" will be valid while connection is >> established? > Yes, it would be valid as far as we don't reset it from another > set_vring_call. So, we should not reset it on reset_device(). > > --yliu Hi Yuanhan, Thanks for checking. I will submit the patch for this today. Tetsuya >> Also I've found a workaround. >> Please execute after step7. >> >> 8. Bind the virtio-net device to virtio-pci kernel driver. >> 9. Bind the virtio-net device to igb_uio. >> 10. Start testpmd in QEMU. >> >> When step8 is executed, connection will be re-established, and testpmd >> on host will be able to receive SET_VRING_CALL. >> Then testpmd on host can start. >> >> Thanks, >> Tetsuya