From owner-freebsd-current@FreeBSD.ORG Tue Jan 6 14:55:27 2015 Return-Path: Delivered-To: freebsd-current@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 87946E99; Tue, 6 Jan 2015 14:55:27 +0000 (UTC) Received: from bigwig.baldwin.cx (bigwig.baldwin.cx [IPv6:2001:470:1f11:75::1]) (using TLSv1 with cipher DHE-RSA-CAMELLIA256-SHA (256/256 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id 5D70B1A92; Tue, 6 Jan 2015 14:55:27 +0000 (UTC) Received: from new-host.home (pool-173-70-85-31.nwrknj.fios.verizon.net [173.70.85.31]) by bigwig.baldwin.cx (Postfix) with ESMTPSA id 6A82EB94F; Tue, 6 Jan 2015 09:55:26 -0500 (EST) Message-ID: <54ABF75D.5060302@FreeBSD.org> Date: Tue, 06 Jan 2015 09:55:25 -0500 From: John Baldwin User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.9; rv:31.0) Gecko/20100101 Thunderbird/31.3.0 MIME-Version: 1.0 To: Craig Rodrigues , Luigi Rizzo Subject: Re: any primer on running bhyve guests sharing disk with host ? References: <20150103161511.GA94237@onelab2.iet.unipi.it> In-Reply-To: Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit X-Greylist: Sender succeeded SMTP AUTH, not delayed by milter-greylist-4.2.7 (bigwig.baldwin.cx); Tue, 06 Jan 2015 09:55:26 -0500 (EST) Cc: freebsd-current Current , Neel Natu X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.18-1 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 06 Jan 2015 14:55:27 -0000 On 1/3/15 1:43 PM, Craig Rodrigues wrote: > On Sat, Jan 3, 2015 at 8:15 AM, Luigi Rizzo wrote: > >> Hi, >> in order to do some kernel testing, I would like to run bhyve guests >> using (through NFS, probably) the host's file system. >> diskless(8) is probably one way to go, i was wondering if >> someone has instructions for that. >> Specifically: >> - how to "bhyveload" a kernel (rather than the full disk image); >> as an alternative, given a kernel, something to build an image >> that can be passed to bhyveload >> >> - how to pass the necessary config (rootpath) to the client >> without having to rely on a specialized dhcp server >> >> I used to be familiar with diskless configs, so i can probably sort >> out the server side myself. >> < Neel already covered -h with bhyveload which you can also use with -H to vmrun.sh, though the other way I do this is to NFS export my work tree from the host to the guest so I can run kgdb on the host but do the build / install in the guest itself. > > I don't think there is a way to do exactly what you want. > I would recommend doing the following: > > (1) Enable bvmdebug in your kernel config: > https://wiki.freebsd.org/BHyVe/gdb > This allows you to do kgdb remote debugging into a bhyve VM. At this point it is probably simpler to use the serial port instead. I have hacked up vmrun.sh locally to always create a /dev/nmdm2B device hooked up to com2 and to add 0x80 to the flags for uart1 in device.hints in all my VMs. You can then use kgdb from the host and 'target remote /dev/nmdm2A'. --- /usr/share/examples/bhyve/vmrun.sh 2014-11-20 18:38:34.000000000 -0500 +++ /home/john/bhyve/vmrun.sh 2015-01-06 09:54:47.000000000 -0500 @@ -230,6 +230,9 @@ nextslot=$(($nextslot + 1)) i=$(($i + 1)) done + if kldstat -qm nmdm; then + devargs="$devargs -l com2,/dev/nmdm${vmname}2B" + fi ${FBSDRUN} -c ${cpus} -m ${memsize} ${apic_opt} -A -H -P \ -g ${gdbport} \ -- John Baldwin