Libguestfs - Jan 2022 - virt-p2v-make-disk Question

On 01/05/22 14:56, Richard W.M. Jones wrote:
> On Wed, Jan 05, 2022 at 01:46:08PM +0100, Tobias Soppa wrote:
>> Dear Richard,
>>
>> Sorry for bothering, but I didn't find another way to ask a
question.
>>
>> Maybe you can point me to a chat or forum to receive support? I am not
>> sure whether I should use the libguestfs mailing list to send my
>> problem it to everyone?
> 
> You can send any questions to libguestfs at redhat.com (without
> needing to subscribe).  Or we're on IRC #guestfs on Libera.
> 
>> For days I'm trying to boot from virt-p2v-make-disk made USB
thumbdrive
>> but was never able to boot from it.
>>
>> I did produce several images in different ways and with different Linux
>> distributions, but the thumb drive is never bootable - not on a
>> physical machine, nor via Ventoy.
>>
>> It works in QEMU though, but I need it running on a physical machine. I
>> need to use (Secure) UEFI for booting and this works with any other
>> disk image.
> 
> Probably UEFI is the problem here - in fact I doubt somehow that
> we support it at all.
The statement "works in QEMU" is unclear. If the QEMU guest in
question
uses OVMF, then both cases (virt and phys) wouldn't differ with regard
to firmware type.

Secure Boot could be an issue too, yes; dependent on how the virt-p2v
UEFI bootloader is signed.
> Is it possible to turn it off and/or use the CMS module?
(*CSM -- compatibility support module)

It could be a workaround, yes.
> 
>> Maybe because these discs are delivered with ISO filesystem and not as
>> .IMG images? I feel I terribly miss something here.
> 
> We probably ought to deliver P2V as a UEFI binary, one day.
I've not delved into virt-p2v yet, but given that it uses GTK, it's
exceedingly unlikely that it can be built as a firmware-level binary
(such as "grub"), considering either UEFI or traditional BIOS.

The virt-p2v binary is an "ELF 64-bit LSB executable, x86-64, version 1
(SYSV), dynamically linked (uses shared libs)", so I think what we'd
actually do is: create a UEFI-bootable Linux image on the USB disk, and
continue using virt-p2v the same way -- once virt-p2v starts (as a Linux
process), the host firmware shouldn't matter.

If this is important, we should likely have an RFE (RHBZ) about it.

Thanks!
Laszlo

On Fri, Jan 07, 2022 at 09:01:35AM +0100, Laszlo Ersek
wrote:
> On 01/05/22 14:56, Richard W.M. Jones wrote:
> > On Wed, Jan 05, 2022 at 01:46:08PM +0100, Tobias Soppa wrote:
> >> Dear Richard,
> >>
> >> Sorry for bothering, but I didn't find another way to ask a
question.
> >>
> >> Maybe you can point me to a chat or forum to receive support? I am
not
> >> sure whether I should use the libguestfs mailing list to send my
> >> problem it to everyone?
> > 
> > You can send any questions to libguestfs at redhat.com (without
> > needing to subscribe).  Or we're on IRC #guestfs on Libera.
> > 
> >> For days I'm trying to boot from virt-p2v-make-disk made USB
thumbdrive
> >> but was never able to boot from it.
> >>
> >> I did produce several images in different ways and with different
Linux
> >> distributions, but the thumb drive is never bootable - not on a
> >> physical machine, nor via Ventoy.
> >>
> >> It works in QEMU though, but I need it running on a physical
machine. I
> >> need to use (Secure) UEFI for booting and this works with any
other
> >> disk image.
> > 
> > Probably UEFI is the problem here - in fact I doubt somehow that
> > we support it at all.
> 
> The statement "works in QEMU" is unclear. If the QEMU guest in
question
> uses OVMF, then both cases (virt and phys) wouldn't differ with regard
> to firmware type.
> 
> Secure Boot could be an issue too, yes; dependent on how the virt-p2v
> UEFI bootloader is signed.
> 
> > Is it possible to turn it off and/or use the CMS module?
> 
> (*CSM -- compatibility support module)
> 
> It could be a workaround, yes.
> 
> > 
> >> Maybe because these discs are delivered with ISO filesystem and
not as
> >> .IMG images? I feel I terribly miss something here.
> > 
> > We probably ought to deliver P2V as a UEFI binary, one day.
> 
> I've not delved into virt-p2v yet, but given that it uses GTK, it's
> exceedingly unlikely that it can be built as a firmware-level binary
> (such as "grub"), considering either UEFI or traditional BIOS.
> 
> The virt-p2v binary is an "ELF 64-bit LSB executable, x86-64, version
1
> (SYSV), dynamically linked (uses shared libs)", so I think what
we'd
> actually do is: create a UEFI-bootable Linux image on the USB disk, and
> continue using virt-p2v the same way -- once virt-p2v starts (as a Linux
> process), the host firmware shouldn't matter.
Right, that's what I meant to say :-)

Rich.
> If this is important, we should likely have an RFE (RHBZ) about it.
> 
> Thanks!
> Laszlo
-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
Read my programming and virtualization blog: http://rwmj.wordpress.com
libguestfs lets you edit virtual machines.  Supports shell scripting,
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