On Mon, May 07, 2012 at 10:25:34PM -0300, Marcelo Tosatti wrote: > On Thu, May 03, 2012 at 02:22:58PM +0300, Avi Kivity wrote: > > This patchset implements unlocked TLB flushing for KVM. An operation that > > generates stale TLB entries can mark the TLB as dirty instead of flushing > > immediately, and then flush after releasing mmu_lock but before returning > > to the guest or the caller. A few call sites are converted too. > > > > Note not all call sites are easily convertible; as an example, sync_page() > > must flush before reading the guest page table. > > Huh? Are you referring to: > > * Note: > * We should flush all tlbs if spte is dropped even though guest is > * responsible for it. Since if we don't, > * kvm_mmu_notifier_invalidate_page > * and kvm_mmu_notifier_invalidate_range_start detect the mapping page > * isn't > * used by guest then tlbs are not flushed, so guest is allowed to > * access the > * freed pages. > * And we increase kvm->tlbs_dirty to delay tlbs flush in this case. > > With an increased dirtied_count the flush can be performed > by kvm_mmu_notifier_invalidate_page. Which is what patch 1 does. Your comment regarding sync_page() above is what is outdated, unless i am missing something. -- 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
