Hi Marcelo, Sorry for the delay. On Sep 9, 2014, at 11:41 PM, Marcelo Tosatti <mtosatti@xxxxxxxxxx> wrote: > On Tue, Jul 22, 2014 at 05:59:42AM +0800, Xiao Guangrong wrote: >> >> On Jul 10, 2014, at 3:12 AM, mtosatti@xxxxxxxxxx wrote: >> >>> Skip pinned shadow pages when selecting pages to zap. >> >> It seems there is no way to prevent changing pinned spte on >> zap-all path? > > Xiao, > > The way would be to reload remote mmus, forcing the vcpu to exit, > zapping a page, then vcpu will pagefault any necessary page via > kvm_mmu_pin_pages. > > kvm_mmu_invalidate_zap_all_pages does: > > - spin_lock(mmu_lock) > - kvm_reload_remote_mmus > ... > - spin_unlock(mmu_lock) > > So its OK to change pinned spte on zap all path. Got it, thanks for your explanation. > >> I am thing if we could move pinned spte to another list (eg. pinned_shadow_pages) >> instead of active list so that it can not be touched by any other free paths. >> Your idea? > > As mentioned it above, it is ok to zap pinned sptes as long w > reload remote mmus request is performed. > > That said, you still consider a separate list? I need to think more about this idea… let’s address it as your patch first. :) -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html