On Tue, 30 Jul 2019 15:34:54 +0200 Paolo Bonzini <pbonz...@redhat.com> wrote:
> On 30/07/19 15:25, Igor Mammedov wrote: > > I'd guess you've meant RAMBlocks instead of memory regions, if that's it > > then yes, every alias pointing to RAM backed memory region will have > > RAMBlock that's points to aliased part of aliased memory region. > > The question is just, does it break migration from old QEMU to new QEMU > on x86 (which has plenty of RAM-backed aliases)? If not, explain that > in the commit message or in a code comment. pc/q35 old<->new new<->old ping pong tests worked fine (qemu with default devices). My understanding was that one needs to call vmstate_register_ram() to make memory region migratable, which marks specific RAMBlock as migratable. So just assigning new RAMBlock to mr->ram_block shouldn't affect migration, unless vmstate_register_ram() is called on alias. I'll add it to commit message. > > Paolo >