From mboxrd@z Thu Jan 1 00:00:00 1970 From: Konrad Rzeszutek Wilk Subject: Re: [PATCH RFC v1 00/13] Introduce HMV without dm and new boot ABI Date: Mon, 22 Jun 2015 14:05:44 -0400 Message-ID: <20150622180544.GA9175@l.oracle.com> References: <1434989487-74940-1-git-send-email-roger.pau@citrix.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from mail6.bemta5.messagelabs.com ([195.245.231.135]) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1Z767F-0001g3-Dz for xen-devel@lists.xenproject.org; Mon, 22 Jun 2015 18:06:41 +0000 Content-Disposition: inline In-Reply-To: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: Stefano Stabellini Cc: elena.ufimtseva@oracle.com, wei.liu2@citrix.com, Ian Campbell , andrew.cooper3@citrix.com, ian.jackson@eu.citrix.com, xen-devel@lists.xenproject.org, boris.ostrovsky@oracle.com, Roger Pau Monne List-Id: xen-devel@lists.xenproject.org On Mon, Jun 22, 2015 at 06:55:12PM +0100, Stefano Stabellini wrote: > Hi Roger, > > given that this patch series is actually using the Xen "hvm" builder, I > take that all the PVH code paths in Xen or the guest kernel are not > actually used, correct? This is more like PV on HVM without QEMU, right? Are you saying it should be called now 'HVM-diet' ? Or 'HVMlite' instead of PVH since it is looking at this from the HVM perspective instead of PVH? > > Do you think think this can work for Dom0 too? > > Would that make all the PVH stuff in Xen and Linux effectively useless? No. The AP bootup is still the same. So would all the hypercalls I think. > > Thanks, > > Stefano > > On Mon, 22 Jun 2015, Roger Pau Monne wrote: > > Before reading any further, keep in mind this is a VERY inital RFC > > prototype series. Many things are not finished, and those that are done > > make heavy use of duck tape in order to keep things into place. > > > > Now that you are warned, this series is split in the following order: > > > > - Patches from 1 to 7 switch HVM domain contruction to use the xc_dom_* > > family of functions, like they are used to build PV domains. > > - Patches from 8 to 13 introduce the creation of HVM domains without > > firmware, which is replaced by directly loading a kernel like it's done > > for PV guests. A new boot ABI based on the discussion in the thread "RFC: > > making the PVH 64bit ABI as stable" is also introduced, although it's not > > finished. > > > > Some things that are missing from the new boot ABI: > > > > - Although it supports loading a ramdisk, there's still now defined way > > into how to pass this ramdisk to the guest. I'm thinking of using a > > HVMPARAM or simply setting a GP register to contain the address of the > > ramdisk. Ideally I would like to support loading more than one ramdisk. > > > > Some patches contain comments after the SoB, which in general describe the > > shortcommings of the implementation. The aim of those is to initiate > > discussion about whether the aproach taken is TRTTD. > > > > I've only tested this on Intel hw, but I see no reason why it shouldn't work > > on AMD. I've managed to boot FreeBSD up to the point were it should > > jump into user-space (I just didn't have a VBD attached to the VM so it just > > sits waiting for a valid disk). I have not tried to boot it any further > > since I think that's fine for the purpose of this series. > > > > The series can also be found in the following git repo: > > > > git://xenbits.xen.org/people/royger/xen.git branch hvm_without_dm_v1 > > > > And for the FreeBSD part: > > > > git://xenbits.xen.org/people/royger/freebsd.git branch new_entry_point_v1 > > > > In case someone wants to give it a try, I've uploaded a FreeBSD kernel that > > should work when booted into this mode: > > > > https://people.freebsd.org/~royger/kernel_no_dm > > > > The config file that I've used is: > > > > > > kernel="/path/to/kernel_no_dm" > > > > builder="hvm" > > device_model_version="none" > > > > memory=128 > > vcpus=1 > > name = "freebsd" > > > > > > Thanks, Roger. > > > > _______________________________________________ > > Xen-devel mailing list > > Xen-devel@lists.xen.org > > http://lists.xen.org/xen-devel > >