Messages in this thread | | | Date | Thu, 11 Sep 2014 15:05:05 +0200 | From | Paolo Bonzini <> | Subject | Re: [PATCH v5 4/7] kvm, mem-hotplug: Reload L1' apic access page on migration in vcpu_enter_guest(). |
| |
Il 11/09/2014 13:30, Gleb Natapov ha scritto: >> > + vmcs_write64(APIC_ACCESS_ADDR, page_to_phys(page)); >> > + /* >> > + * Do not pin apic access page in memory so that memory >> > + * hotplug process is able to migrate it. >> > + */ >> > + put_page(page); >> > } > This code is in prepare_vmcs02() and is executed during L1->L2 vmentry. What happens > when apic access page is migrated while L2 is running? It needs to be update somewhere.
Before it is migrated, the MMU notifier is called and will force a vmexit on all CPUs. The reload code will call GUP again on the page again and swap it in.
Paolo
| |