Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull kvm fixes from Paolo Bonzini:
 "The main change here is a revert of reverts. We recently simplified
  some code that was thought unnecessary; however, since then KVM has
  grown quite a few cond_resched()s and for that reason the simplified
  code is prone to livelocks---one CPUs tries to empty a list of guest
  page tables while the others keep adding to them. This adds back the
  generation-based zapping of guest page tables, which was not
  unnecessary after all.

  On top of this, there is a fix for a kernel memory leak and a couple
  of s390 fixlets as well"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
  KVM: x86/mmu: Reintroduce fast invalidate/zap for flushing memslot
  KVM: x86: work around leak of uninitialized stack contents
  KVM: nVMX: handle page fault in vmread
  KVM: s390: Do not leak kernel stack data in the KVM_S390_INTERRUPT ioctl
  KVM: s390: kvm_s390_vm_start_migration: check dirty_bitmap before using it as target for memset()

1 files changed, 3 insertions, 1 deletions

diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c
index ced9fba32598..a3cba321b5c5 100644
--- a/arch/x86/kvm/vmx/nested.c
+++ b/arch/x86/kvm/vmx/nested.c
@@ -4540,6 +4540,7 @@ static int handle_vmread(struct kvm_vcpu *vcpu)
         int len;
         gva_t gva = 0;
         struct vmcs12 *vmcs12;
+        struct x86_exception e;
         short offset;
 
         if (!nested_vmx_check_permission(vcpu))
@@ -4588,7 +4589,8 @@ static int handle_vmread(struct kvm_vcpu *vcpu)
                                 vmx_instruction_info, true, len, &gva))
                         return 1;
                 /* _system ok, nested_vmx_check_permission has verified cpl=0 */
-                kvm_write_guest_virt_system(vcpu, gva, &field_value, len, NULL);
+                if (kvm_write_guest_virt_system(vcpu, gva, &field_value, len, &e))
+                        kvm_inject_page_fault(vcpu, &e);
         }
 
         return nested_vmx_succeed(vcpu);