Re: [Qemu-devel] Question about xen disk unplug support for ahci missed in qemu

[Stefano Stabellini <stefano.stabellini@eu.citrix.com>]

On Fri, 16 Oct 2015, Fabio Fantoni wrote:
> Il 16/10/2015 12:13, Anthony PERARD ha scritto:
> > On Fri, Oct 16, 2015 at 10:32:44AM +0200, Fabio Fantoni wrote:
> > > Il 15/10/2015 20:02, Anthony PERARD ha scritto:
> > > > On Thu, Oct 15, 2015 at 06:27:17PM +0200, Fabio Fantoni wrote:
> > > > > Il 14/10/2015 13:06, Stefano Stabellini ha scritto:
> > > > > > I would suggest Fabio to avoid AHCI disks altogether and just use
> > > > > > OVMF
> > > > > > with PV disks only and Anthony's patch to libxl to avoid creating
> > > > > > any
> > > > > > IDE disks: http://marc.info/?l=xen-devel&m=144482080812353.
> > > > > > 
> > > > > > Would that work for you?
> > > > > Thanks for the advice, I tried it:
> > > > > https://github.com/Fantu/Xen/commits/rebase/m2r-testing-4.6
> > > > > 
> > > > > I installed W10 pro 64 bit with ide disk, installed the win pv drivers
> > > > > and
> > > > > after changed to xvdX instead hdX, is the only change needed, right?
> > > > > Initial boot is ok (ovmf part about pv disks seems ok) but windows
> > > > > boot
> > > > > fails with problem with pv drivers.
> > > > > In attachment full qemu log with xen_platform trace and domU's xl cfg.
> > > > > 
> > > > > Someone have windows domUs with ovmf and pv disks only working? If yes
> > > > > can
> > > > > tell me the difference to understand what can be the problem please?
> > > > When I worked on the PV disk implementation in OVMF, I was able to boot
> > > > a Windows 8 with pv disk only.
> > > > 
> > > > I don't have access to the guest configuration I was using, but I think
> > > > one
> > > > difference would be the viridian setting, I'm pretty sure I did not set
> > > > it.
> > > > 
> > > I tried with viridian disabled but did the same thing, looking cdrom as
> > > latest thing before xenbug trace in qemu log I tried also to remove it but
> > > also in this case don't boot correctly, full qemu log in attachment.
> > > I don't know if is a ovmf thing to improve (like what seems in Laszlo and
> > > Kevin mails) or xen winpv drivers unexpected case, have you tried also
> > > with
> > > latest winpv builds? (for exclude regression)
> > No, I did not tried the latest winpv drivers.
> > 
> > Sorry I can help much more that that. When I install this win8 guest tried
> > to boot it with pv drivers only, that was more than a year ago. I have not
> > check if it's still working. (Also I can not try anything more recent,
> > right now.)
> > 
> 
> I did many other tests, retrying with ide first boot working but show pv
> devices not working, I did another reboot (with ide) and pv devices was
> working, after I retried with pv (xvdX) and boot correctly.
> After other tests I found that with empty cdrom device (required for xl
> cd-insert/cd-eject) boot stop at start (tianocore image), same result with ide
> instead.
> From xl cfg:
> disk=['/mnt/vm/disks/W10UEFI.disk1.cow-sn1,qcow2,xvda,rw',',raw,xvdb,ro,cdrom']
> With seabios domU boot also with empty cdrom.
> In qemu log I found only these that can be related:
> > xen be: qdisk-51728: error: Could not open image: No such file or directory
> > xen be: qdisk-51728: initialise() failed
> And latest xl dmesg line is:
> > (d1) Invoking OVMF ...
> 
> If you need more informations/test tell me and I'll post them.

Are you saying that without any cdrom drives, it works correctly?