From 8234b22e1c3287307c53655b16478cf8f5071555 Mon Sep 17 00:00:00 2001 From: Avi Kivity Date: Mon, 27 Dec 2010 12:08:45 +0200 Subject: KVM: MMU: Don't flush shadow when enabling dirty tracking Instead, drop large mappings, which were the reason we dropped shadow. Signed-off-by: Avi Kivity Signed-off-by: Marcelo Tosatti --- arch/x86/kvm/mmu.c | 12 ++++++++---- virt/kvm/kvm_main.c | 7 +------ 2 files changed, 9 insertions(+), 10 deletions(-) diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c index f02b8edc3d4..ccacf0b1b54 100644 --- a/arch/x86/kvm/mmu.c +++ b/arch/x86/kvm/mmu.c @@ -3538,14 +3538,18 @@ void kvm_mmu_slot_remove_write_access(struct kvm *kvm, int slot) if (!test_bit(slot, sp->slot_bitmap)) continue; - if (sp->role.level != PT_PAGE_TABLE_LEVEL) - continue; - pt = sp->spt; - for (i = 0; i < PT64_ENT_PER_PAGE; ++i) + for (i = 0; i < PT64_ENT_PER_PAGE; ++i) { + if (sp->role.level != PT_PAGE_TABLE_LEVEL + && is_large_pte(pt[i])) { + drop_spte(kvm, &pt[i], + shadow_trap_nonpresent_pte); + --kvm->stat.lpages; + } /* avoid RMW */ if (is_writable_pte(pt[i])) update_spte(&pt[i], pt[i] & ~PT_WRITABLE_MASK); + } } kvm_flush_remote_tlbs(kvm); } diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index f29abeb6a91..a3a8f5fb369 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -621,7 +621,7 @@ int __kvm_set_memory_region(struct kvm *kvm, struct kvm_userspace_memory_region *mem, int user_alloc) { - int r, flush_shadow = 0; + int r; gfn_t base_gfn; unsigned long npages; unsigned long i; @@ -741,8 +741,6 @@ skip_lpage: if (kvm_create_dirty_bitmap(&new) < 0) goto out_free; /* destroy any largepage mappings for dirty tracking */ - if (old.npages) - flush_shadow = 1; } #else /* not defined CONFIG_S390 */ new.user_alloc = user_alloc; @@ -813,9 +811,6 @@ skip_lpage: kvm_free_physmem_slot(&old, &new); kfree(old_memslots); - if (flush_shadow) - kvm_arch_flush_shadow(kvm); - return 0; out_free: -- cgit v1.2.3