[libvirt] [PATCH 3/8] qemu: Fix memory locking limit calculation

[Andrea Bolognani]

On Mon, 2017-03-27 at 14:24 +0200, Martin Kletzander wrote:
[...]
> > @@ -6220,10 +6220,13 @@ qemuDomainGetMemLockLimitBytes(virDomainDefPtr def)
> >         goto done;
> >     }
> > 
> > -    if (def->mem.locked) {
> > -        memKB = virDomainDefGetMemoryTotal(def) + 1024 * 1024;
> > -        goto done;
> > -    }
> > +    /* If the guest wants its memory to be locked, we need to raise the memory
> > +     * locking limit so that the OS will not refuse allocation requests;
> > +     * however, there is no reliable way for us to figure out how much memory
> > +     * the QEMU process will allocate for its own use, so our only way out is
> > +     * to remove the limit altogether. Use with extreme care */
> > +    if (def->mem.locked)
> > +        return VIR_DOMAIN_MEMORY_PARAM_UNLIMITED;
> 
> So there is no way how one can limit the size of the memlock, other than
> setting the hard limit?

Correct.

> Are you planning on adding new element to the
> domain XML which would allow setting this number as well?

I do. Unless I forget about it again, of course :)

-- 
Andrea Bolognani / Red Hat / Virtualization