On Tue, 27 Oct 2015 10:31:21 +0200 "Michael S. Tsirkin" <m...@redhat.com> wrote:
> On Mon, Oct 26, 2015 at 02:24:32PM +0100, Igor Mammedov wrote: > > Yep it's workaround but it works around QEMU's broken virtio > > implementation in a simple way without need for guest side changes. > > > > Without foreseeable virtio fix it makes memory hotplug unusable and even > > more so if there were a virtio fix it won't fix old guests since you've > > said that virtio fix would require changes of both QEMU and guest sides. > > What makes it not foreseeable? > Apparently only the fact that we have a work-around in place so no one > works on it. I can code it up pretty quickly, but I'm flat out of time > for testing as I'm going on vacation soon, and hard freeze is pretty > close. I can lend a hand for testing part. > > GPA space is kind of cheap, but wasting it in chunks of 512M > seems way too aggressive. hotplug region is sized with 1Gb alignment reserve per DIMM so we aren't actually wasting anything here.