From owner-freebsd-net@freebsd.org Fri Mar 30 06:51:58 2018 Return-Path: Delivered-To: freebsd-net@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id D5F7EF76CEC for ; Fri, 30 Mar 2018 06:51:57 +0000 (UTC) (envelope-from reshadpatuck1@gmail.com) Received: from mail-pg0-x22c.google.com (mail-pg0-x22c.google.com [IPv6:2607:f8b0:400e:c05::22c]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (Client CN "smtp.gmail.com", Issuer "Google Internet Authority G2" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 539DF79E4B for ; Fri, 30 Mar 2018 06:51:57 +0000 (UTC) (envelope-from reshadpatuck1@gmail.com) Received: by mail-pg0-x22c.google.com with SMTP id n11so4592181pgp.4 for ; Thu, 29 Mar 2018 23:51:57 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=date:user-agent:in-reply-to:references:mime-version :content-transfer-encoding:subject:to:cc:from:message-id; bh=DepBnULdPdJWoq92JrtKlWr3tmiC+vmgMD2AhhE4lNc=; b=r9juvM3OF4ZNGUYdSFVNWCv9SD65lWUZboPjUZ7lbgsmFmIiHZwAJwx/s6oyBRI8UM OjX6mMu3xdc1JmzGzaGcX8ZV3klQZqew3wPbc8rJRl9b5FhyGMdaaOXlPKXEmeVOhX4w HpKvgpAy3X6M06e+9E3qcdxOi4qU72fiaFnmqN8x1StqAaPITbWbhCd+WT0gW7XH767a S/rxT56imNRF3kK9XSeUl4xSkDSQwMS3gvYbYPcN/hLM1YhHnln7VXkxOVxTosb2mQpz 6AoXR7xrrwqY9npN2qqN5a2qlJtEUcAUToCVoXiiPDUjkyRg/uOGJPNcIgBkz33IURof FKvA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:user-agent:in-reply-to:references :mime-version:content-transfer-encoding:subject:to:cc:from :message-id; bh=DepBnULdPdJWoq92JrtKlWr3tmiC+vmgMD2AhhE4lNc=; b=fX9tatq3508HO3C3yswNET/i+bs3wCQryFfp4pyxAzdxZbfzCPGoCHPiEVVi1P6NG3 VoVAHAtvLzpqvcbKpzBKFCsgVRnUlR9BWpAol7lDQykWCVFy7u0uaZHnw+L3c/5bMgxX elt8z6QDevRZdN4tuZaKJiIT56k4NidMHu14F1u7gS/h4JPI33UB0w/IY7UrBtHE7MGM LhcauEiyTpgfBSJJq9IgnYNOUEZ6NrfqthgWbiuM/rQg9Xt9ZCqs9JH7rgvCQp3tvtw0 PDnv0nxYE01Ayyg1HNtSMjCEQC4A9LQJzw8QgP3BXm1YO30RAw3wgIC5QQ4Ossuds3sr CIHw== X-Gm-Message-State: AElRT7GjqaOMUHRJLIHwDDGK35AMulY05xivUQm/sIZAW1KgYIaZlS1s 1lzDReMilq+wLSfUz4jRlriJnFmkzoY= X-Google-Smtp-Source: AIpwx4/ouIIm89nskZl90lXCcNvicA41szonMuG07K8QIsoPmrigCte9kxj2JuIJHjfIJGhnoqhJPA== X-Received: by 2002:a17:902:7045:: with SMTP id h5-v6mr6296382plt.1.1522392716270; Thu, 29 Mar 2018 23:51:56 -0700 (PDT) Received: from ?IPv6:2402:3a80:654:6bfb:d0df:e42a:63a5:b4f1? ([2402:3a80:654:6bfb:d0df:e42a:63a5:b4f1]) by smtp.gmail.com with ESMTPSA id r9sm16165766pfg.128.2018.03.29.23.51.54 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 29 Mar 2018 23:51:55 -0700 (PDT) Date: Fri, 30 Mar 2018 12:21:50 +0530 User-Agent: K-9 Mail for Android In-Reply-To: <10647168-66DF-48CD-9121-9CC2B00848D4@sigsegv.be> References: <71B1A1BD-6FCF-47BB-9523-CCAAC03799A5@sigsegv.be> <1563563.7DUcjoHYMp@reshadlaptop.patuck.net> <1D6101CD-BCB4-4206-838B-1A75152ACCC4@sigsegv.be> <38C78C2B-87D2-4225-8F4B-A5EA48BA5D17@patuck.net> <5803CAA2-DC4A-4E49-B715-6DE472088DDD@sigsegv.be> <9CAB4522-0B0A-42BF-B9A4-BF36AFC60286@patuck.net> <7202AFF2-A314-41FE-BD13-C4C77A95E106@sigsegv.be> <2D15ABDE-0C25-4C97-AEA6-0098459A2795@lists.zabbadoz.net> <277350C5-3B1F-4105-AF0A-886B6133218E@sigsegv.be> <97945712-B53E-4CF6-B20E-6001CF40CDFC@gmail.com> <10647168-66DF-48CD-9121-9CC2B00848D4@sigsegv.be> MIME-Version: 1.0 Subject: Re: [vnet] [epair] epair interface stops working after some time To: Kristof Provost CC: freebsd-net@freebsd.org, "Bjoern A. Zeeb" , Reshad Patuck From: Reshad Patuck Message-ID: <6FF884DA-1AA9-4488-9798-7B16AAFED243@gmail.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable X-Content-Filtered-By: Mailman/MimeDel 2.1.25 X-BeenThere: freebsd-net@freebsd.org X-Mailman-Version: 2.1.25 Precedence: list List-Id: Networking and TCP/IP with FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 30 Mar 2018 06:51:58 -0000 Hi, I have filed a bug for this issue and cc'd both of you in it=2E https://bugs=2Efreebsd=2Eorg/bugzilla/show_bug=2Ecgi?id=3D227100 Best, Reshad On 29 March 2018 6:39:13 PM IST, Kristof Provost wr= ote: >On 29 Mar 2018, at 14:48, Reshad Patuck wrote: >> pulling the 'net=2Elink=2Eepair=2Enetisr_maxqlen' down does seem to mak= e=20 >> this occur faster=2E >> =E2=80=8B >Good, I think my hypothesis about where the issue lies is correct then=2E >You should be able to avoid (or at least reduce the frequency of) the=20 >issue by increasing the value on your system(s)=2E > >> When I dropped it to 2 like Kristof did and I have the same symptoms=20 >> on a box which was not exhibiting the problems manually began to have > >> the same symptoms=2E >> Bumping it back up to 2100 did not restore the functionality (I don't > >> know if it should)=2E >> =E2=80=8B >It=E2=80=99s good to know this=2E It doesn=E2=80=99t surprise me that it = doesn=E2=80=99t fix=20 >things=2E >Something=E2=80=99s wrong in the code which handle an overflow of the net= isr=20 >queue in the epair driver=2E Once that happens the IFF_DRV_OACTIVE flag= =20 >gets set, and we keep enqueuing outside the netisr queue=2E >Somehow we never end up back in epair_nh_drainedcpu(), so the flag >never=20 >gets cleared and the driver never recovers=2E > >> I will create a PR for this later today with all the information I=20 >> have gathered so that we can have it all in one place=2E >> >Thanks=2E Please cc me on it=2E I=E2=80=99ll see if I can figure out what= the=20 >problem is, but we might need someone smarter, so cc Bjoern too=2E > >Regards, >Kristof