KVM: MMU: skip global pgtables on sync due to cr3 switch

Skip syncing global pages on cr3 switch (but not on cr4/cr0). This is
important for Linux 32-bit guests with PAE, where the kmap page is
marked as global.

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>

1 files changed, 4 insertions, 0 deletions

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 7a2aeba0bfbd..774db00d2db6 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -104,6 +104,7 @@ struct kvm_stats_debugfs_item debugfs_entries[] = {
         { "mmu_recycled", VM_STAT(mmu_recycled) },
         { "mmu_cache_miss", VM_STAT(mmu_cache_miss) },
         { "mmu_unsync", VM_STAT(mmu_unsync) },
+        { "mmu_unsync_global", VM_STAT(mmu_unsync_global) },
         { "remote_tlb_flush", VM_STAT(remote_tlb_flush) },
         { "largepages", VM_STAT(lpages) },
         { NULL }
@@ -315,6 +316,7 @@ void kvm_set_cr0(struct kvm_vcpu *vcpu, unsigned long cr0)
         kvm_x86_ops->set_cr0(vcpu, cr0);
         vcpu->arch.cr0 = cr0;
 
+        kvm_mmu_sync_global(vcpu);
         kvm_mmu_reset_context(vcpu);
         return;
 }
@@ -358,6 +360,7 @@ void kvm_set_cr4(struct kvm_vcpu *vcpu, unsigned long cr4)
         }
         kvm_x86_ops->set_cr4(vcpu, cr4);
         vcpu->arch.cr4 = cr4;
+        kvm_mmu_sync_global(vcpu);
         kvm_mmu_reset_context(vcpu);
 }
 EXPORT_SYMBOL_GPL(kvm_set_cr4);
@@ -4113,6 +4116,7 @@ struct  kvm *kvm_arch_create_vm(void)
                 return ERR_PTR(-ENOMEM);
 
         INIT_LIST_HEAD(&kvm->arch.active_mmu_pages);
+        INIT_LIST_HEAD(&kvm->arch.oos_global_pages);
         INIT_LIST_HEAD(&kvm->arch.assigned_dev_head);
 
         /* Reserve bit 0 of irq_sources_bitmap for userspace irq source */