Re: [Qemu-devel] [PATCH 03/11] pc: check if KVM has enough memory slots for DIMM devices

[Igor Mammedov <imammedo@redhat.com>]

On Mon, 03 Nov 2014 18:32:51 +0100
Paolo Bonzini <pbonzini@redhat.com> wrote:

> 
> 
> On 03/11/2014 18:00, Igor Mammedov wrote:
> >> > This will always be off by 4 or so due to system RAM and ROM
> >> > slots.  I think patch 1 is enough.
> > The goal of this patch is to prevent starting guest with not
> > supported amount of lots requested on CLI with -m slots=too_much,
> > patch 1 won't prevent user from it.
> 
> Understood.  But I think -m slots=too_much is not an important
> problem. What is problematic is filling those slots, which patch 1
> will help with.

From user's pov it's still error, i.e. he asked on CLI for one amount
of hotpluggable slots and couldn't use all of them at runtime.

I think in addition to this patch we need QMP accessible parameter for
libvirt to tell limit, so that upper layers could tell user how many
slot it's possible to use. something like this:
 /machine/available_memory_slots


> 
> Paolo