KVM: x86 emulator: commit rflags as part of registers commit

Make sure that rflags is committed only after successful instruction
emulation.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>

3 files changed, 8 insertions, 2 deletions

diff --git a/arch/x86/include/asm/kvm_emulate.h b/arch/x86/include/asm/kvm_emulate.h
index b5e12c58386..a1319c82050 100644
--- a/arch/x86/include/asm/kvm_emulate.h
+++ b/arch/x86/include/asm/kvm_emulate.h
@@ -136,6 +136,7 @@ struct x86_emulate_ops {
         ulong (*get_cr)(int cr, struct kvm_vcpu *vcpu);
         void (*set_cr)(int cr, ulong val, struct kvm_vcpu *vcpu);
         int (*cpl)(struct kvm_vcpu *vcpu);
+        void (*set_rflags)(struct kvm_vcpu *vcpu, unsigned long rflags);
 };
 
 /* Type, address-of, and value of an instruction's operand. */
diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c
index ab3fff5bf7c..48de4b89005 100644
--- a/arch/x86/kvm/emulate.c
+++ b/arch/x86/kvm/emulate.c
@@ -2972,6 +2972,7 @@ writeback:
         /* Commit shadow register state. */
         memcpy(ctxt->vcpu->arch.regs, c->regs, sizeof c->regs);
         kvm_rip_write(ctxt->vcpu, c->eip);
+        ops->set_rflags(ctxt->vcpu, ctxt->eflags);
 
 done:
         return (rc == X86EMUL_UNHANDLEABLE) ? -1 : 0;
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index b4d3363b78e..247e805a041 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -3649,6 +3649,11 @@ static void emulator_set_segment_selector(u16 sel, int seg,
         kvm_set_segment(vcpu, &kvm_seg, seg);
 }
 
+static void emulator_set_rflags(struct kvm_vcpu *vcpu, unsigned long rflags)
+{
+        kvm_x86_ops->set_rflags(vcpu, rflags);
+}
+
 static struct x86_emulate_ops emulate_ops = {
         .read_std            = kvm_read_guest_virt_system,
         .write_std           = kvm_write_guest_virt_system,
@@ -3666,6 +3671,7 @@ static struct x86_emulate_ops emulate_ops = {
         .get_cr              = emulator_get_cr,
         .set_cr              = emulator_set_cr,
         .cpl                 = emulator_get_cpl,
+        .set_rflags          = emulator_set_rflags,
 };
 
 static void cache_all_regs(struct kvm_vcpu *vcpu)
@@ -3786,8 +3792,6 @@ restart:
                 return EMULATE_DO_MMIO;
         }
 
-        kvm_x86_ops->set_rflags(vcpu, vcpu->arch.emulate_ctxt.eflags);
-
         if (vcpu->mmio_is_write) {
                 vcpu->mmio_needed = 0;
                 return EMULATE_DO_MMIO;