From owner-freebsd-virtualization@FreeBSD.ORG Wed Jun 10 20:54:25 2015 Return-Path: Delivered-To: freebsd-virtualization@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [8.8.178.115]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTPS id 34D26A33; Wed, 10 Jun 2015 20:54:25 +0000 (UTC) (envelope-from stefan.andritoiu@gmail.com) Received: from mail-ob0-x242.google.com (mail-ob0-x242.google.com [IPv6:2607:f8b0:4003:c01::242]) (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 F130E1E7A; Wed, 10 Jun 2015 20:54:24 +0000 (UTC) (envelope-from stefan.andritoiu@gmail.com) Received: by obcwm4 with SMTP id wm4so6145857obc.3; Wed, 10 Jun 2015 13:54:24 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :content-type; bh=T08klaNeBVKiGJnMwoeA+MxMQUXCEEVovrF8+b80o5o=; b=pmBl0WYB8TFoNe/LrPD35MnQw3xw+f2eDSn1KRAZdzrWUq6oGnLH1Z/Nb68vRLREhW B66npZ1kA+ceJczYZgzyUTWDacuUBgZhdlYzYQ0BFnWnt78bu8fcD2hG/+yDjxnXA6C8 Lw6O9Zcgsy9CPaTv52I8+O4oZ3XzLz89mYzMTmCpng7Y5MzIgw8rZHgqQju60qPLv+dL YA5EJHFGMTHqwBok5cb+Mg3tuZIFslmgWCxqL/YzNPjrbC8sC2SnmXFDvmPFGP7ltwqi /nPnPcxcPwhfkAFM/uQpgrtfitvlluYoE48XypIkDPHj4ogVeiovEFR9K/auMEl2qfRm XNXg== MIME-Version: 1.0 X-Received: by 10.202.50.198 with SMTP id y189mr4257205oiy.21.1433969664389; Wed, 10 Jun 2015 13:54:24 -0700 (PDT) Received: by 10.60.82.168 with HTTP; Wed, 10 Jun 2015 13:54:24 -0700 (PDT) In-Reply-To: <5578A0D7.1080505@freebsd.org> References: <5578A0D7.1080505@freebsd.org> Date: Wed, 10 Jun 2015 23:54:24 +0300 Message-ID: Subject: Re: Gang scheduling implementation in the ULE scheduler From: Stefan Andritoiu To: Peter Grehan , freebsd-virtualization@freebsd.org Content-Type: text/plain; charset=UTF-8 X-BeenThere: freebsd-virtualization@freebsd.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: "Discussion of various virtualization techniques FreeBSD supports." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 10 Jun 2015 20:54:25 -0000 Hi Peter, Yes, I think it is lightly loaded. I am trying to run a FreeBSD guest with 2 VCPUs on a 4 CPU host, with no other program running. But I am having the same problem even when I start a 1 VCPU guest. later, Stefan On Wed, Jun 10, 2015 at 11:40 PM, Peter Grehan wrote: > Hi Stefan, > >> When I start a Virtual Machine, during the guest's boot, IPIs are sent >> and received correctly between CPUs, but after a few seconds I get: >> spin lock 0xffffffff8164c290 (smp rendezvous) held by >> 0xfffff8000296c000 (tid 100009) too long >> panic: spin lock held too long > > > Is this on a lightly loaded machine ? I've not looked at your diff in > detail but it's possibly a code path where a spinlock wasn't unlocked, > leaving another CPU spinning. > > later, > > Peter. >