Re: [PATCH v2] libxl: Add suppress-vmdesc to QEMU machine

[Anthony PERARD <anthony.perard@xxxxxxxxxx>]

On Tue, Nov 03, 2020 at 10:48:44AM +0000, Wei Liu wrote:
> On Thu, Oct 29, 2020 at 03:03:32PM -0400, Jason Andryuk wrote:
> > The device model state saved by QMP xen-save-devices-state doesn't
> > include the vmdesc json.  When restoring an HVM, xen-load-devices-state
> > always triggers "Expected vmdescription section, but got 0".  This is
> > not a problem when restore comes from a file.  However, when QEMU runs
> > in a linux stubdom and comes over a console, EOF is not received.  This
> > causes a delay restoring - though it does restore.
> > 
> > Setting suppress-vmdesc skips looking for the vmdesc during restore and
> > avoids the wait.
> > 
> > QEMU 5.2 enables suppress-vmdesc by default for xenfv, but this change
> > sets it manually for xenfv and xen_platform_pci=0 when -machine pc is
> > use.
> > 
> > QEMU commit 9850c6047b8b "migration: Allow to suppress vmdesc
> > submission" added suppress-vmdesc in QEMU 2.3.
> > 
> > Signed-off-by: Jason Andryuk <jandryuk@xxxxxxxxx>

:-(, sorry, I never received that email.

> > ---
> > QEMU 2.3 came out in 2015, so setting suppress-vmdesc unilaterally
> > should be okay...  Is this okay?


> Anthony, what is your opinion on this?

That it's fine, and I actually asked for the libxl patch. For reference,
QEMU 2.3 is in qemu-xen-4.7.

So,
Acked-by: Anthony PERARD <anthony.perard@xxxxxxxxxx>

Thanks,

-- 
Anthony PERARD