From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pg1-f196.google.com (mail-pg1-f196.google.com [209.85.215.196]) by dpdk.org (Postfix) with ESMTP id 0D8C01B122 for ; Wed, 5 Dec 2018 17:03:56 +0100 (CET) Received: by mail-pg1-f196.google.com with SMTP id 17so9232472pgg.1 for ; Wed, 05 Dec 2018 08:03:55 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=networkplumber-org.20150623.gappssmtp.com; s=20150623; h=date:from:to:cc:subject:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=cDg8kgzLmHHTzQDbvFwX285pGa3tentBRge8cxraQrQ=; b=tX2zyeg7+sqhEuWN+wg4R6m9+EN03Tv/7lSlZqSizUIKU7LwdhemS7hqr6f+Hi4pOz mhECSAO0DT3pIdZUpY9/C6ffhKIIO+VBKBd9t6zYTSAhVZT+pmegnmza4pQ2W+XfQpEM Gz7sZqq14AFanxDbp5ZElUq9tDaOCLxl9LqGIM00Kka9LVhuBZmlUDgQiAvzkqB1GmvA ExbzQXtSMo6xDF4wLJBXCjpT5LqI0c3CNFpwmGWFTT7rxOxvOioFlXWRrHTL/PO8u7j1 4Hgmj6mvte/5cgG+oxgdFix+imJXtPGvDBBhYC8I6JP8RwtVDKknbKHuB0OuSiCY2U0P 2J0g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=cDg8kgzLmHHTzQDbvFwX285pGa3tentBRge8cxraQrQ=; b=cdgLymiYR77J7XEsgdWzQF6MNh6VwW+ghX8HvhM6isrDzo8Kq5vjDFc7vaYhiJeN2q 9O9JSgNJ6I8O8SV8JKN6I+qaLlPWHNfN1BQowzSFL2AvE7jJ4rITI6UnpgkeQmhkj6Kq vWu4JxNBaEIAC4qOKJB/9g0t8XChcUBKJEMVp8ahjLNVEV16pfxNIuQvJCXSW/cq9iX0 d2+wUvxj8irs8bBLtSSFseFjDbWrDtJ4U7pDSKIjjEiu+ZdtplczccrQJUfNvLRQ6StR 4cJeJ+YfzsKB1h/3SjvJ1ithLsHSx104J2uqcEV4lmCXS2l0ywvFB1WH4164dnEYrzSi KGLQ== X-Gm-Message-State: AA+aEWaNjVu40rmMvpVT1Cgxyc01rg+W+Ni470PGBFkEcNz9ftoW8rx6 d+FCMM1RKrR5P4vmZMYpOGXYGUbWMds= X-Google-Smtp-Source: AFSGD/XZTHgVHTHvozuuMcImhg4/fH7ez3Vl1oCFBXI8b7CSJeyLT20yq6/dC7E/JaYorHVvttvLvw== X-Received: by 2002:a62:5dd1:: with SMTP id n78mr24482001pfj.58.1544025835078; Wed, 05 Dec 2018 08:03:55 -0800 (PST) Received: from xeon-e3 (204-195-22-127.wavecable.com. [204.195.22.127]) by smtp.gmail.com with ESMTPSA id f6sm30633106pfg.188.2018.12.05.08.03.54 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Wed, 05 Dec 2018 08:03:55 -0800 (PST) Date: Wed, 5 Dec 2018 08:03:51 -0800 From: Stephen Hemminger To: Gareth Bradshaw Cc: "users@dpdk.org" Message-ID: <20181205080351.10936ea4@xeon-e3> In-Reply-To: References: MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Subject: Re: [dpdk-users] Hyper-V multi-queue not working on Kernel v4.20 X-BeenThere: users@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: DPDK usage discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 05 Dec 2018 16:03:56 -0000 On Wed, 5 Dec 2018 11:05:58 +0000 Gareth Bradshaw wrote: > Hi, > > I'm developing a DPDK application for Hyper-V and would like to use Kernel v4.20 as it fixes a crash in previous kernels (per this pull request) but multi-queue support seems to have broken in that kernel. It works in kernels 4.17, 4.18 and 4.19. > > Using testpmd with parameters "--forward-mode=txonly --nb-cores=3 --txq=3 --rxq=3" I get the following error "vmbus_uio_get_subchan(): invalid subchannel id 0". > > Tracing the code a bit I find that it's trying to read /sys/bus/devices//channels/21/subchannel_id but when I try to cat the same file I get the error "Invalid argument". I've compared to previous kernel versions and see the following differences: > > * When the VM boots, the device is bound to the kernel driver and there are 4 channels on both kernel versions. It's a 4 core VM. > * When I bind the device to uio_hv_generic, kernel v.19.5 (and previous) has a single channel and it has a valid subchannel_id. On kernel 4.20 the 4 channel folders remain but they are all invalid. > * When I start testpmd with 3 queues, on kernel v4.19.5 two additional channels are created, they're valid and testpmd works as expected. On kernel 4.20 the 4 invalid channels remain invalid and testpmd gives the error I mentioned. > > Any help getting this working would be greatly appreciated. > > Thanks > Gareth > > > > > > There is a race that shows up in sub channel initialization, it is being worked on the development mailing list. No resolution yet.