Bug#784688: Thousands of "xen:balloon: Cannot add additional memory (-17) messages" despite dom0 ballooning disabled

[Andy Smith <andy@strugglers.net>]

Hi Ian,

On Fri, Jan 29, 2016 at 02:57:23PM +0000, Ian Campbell wrote:
> I spent a bit of time investigating this, but sadly I'm not able to
> reproduce the basis failure.

FWIW it was me who reported this with the packages in Debian stable
(linux-image-3.16.0-4-amd64 3.16.7-ckt20-1+deb8u3,
xen-hypervisor-4.4-amd64 4.4.1-9+deb8u3) when using
"dom0_mem=1024M,max:1024M" on the hypervisor command line.

I must admit I found this bug when searching for the error message,
and have only been seeing it printed a couple of times at guest
shutdown, not thousands of times.

So if having it printed a couple of times isn't considered a bug,
I'm sorry if I've led you astray here. Might be worth finding a way
to remove it anyway though; anyone having a problem is going to keep
searching for it thinking it is relevant to their case.

At the moment I am avoiding seeing the message at all by running with
only "dom0_mem=1024M" on the command line. What's the disadvantage
of not having the "max:1024M" there?

Cheers,
Andy