From 2d04a05bd7e93c13f13a82ac40de4065a99d069b Mon Sep 17 00:00:00 2001
From: Avi Kivity <avi@redhat.com>
Date: Wed, 20 Apr 2011 15:32:49 +0300
Subject: [PATCH] KVM: x86 emulator: emulate CLTS internally
Avoid using ctxt->vcpu; we can do everything with ->get_cr() and ->set_cr().
A side effect is that we no longer activate the fpu on emulated CLTS; but that
should be very rare.
Signed-off-by: Avi Kivity <avi@redhat.com>
---
arch/x86/include/asm/kvm_host.h | 1 -
arch/x86/kvm/emulate.c | 12 +++++++++++-
arch/x86/kvm/x86.c | 7 -------
3 files changed, 11 insertions(+), 9 deletions(-)
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index a8616ca8320e..9c3567e0f730 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -691,7 +691,6 @@ int kvm_fast_pio_out(struct kvm_vcpu *vcpu, int size, unsigned short port);
void kvm_emulate_cpuid(struct kvm_vcpu *vcpu);
int kvm_emulate_halt(struct kvm_vcpu *vcpu);
int emulate_invlpg(struct kvm_vcpu *vcpu, gva_t address);
-int emulate_clts(struct kvm_vcpu *vcpu);
int kvm_emulate_wbinvd(struct kvm_vcpu *vcpu);
void kvm_get_segment(struct kvm_vcpu *vcpu, struct kvm_segment *var, int seg);
diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c
index 6a5125328669..2b903a326096 100644
--- a/arch/x86/kvm/emulate.c
+++ b/arch/x86/kvm/emulate.c
@@ -2579,6 +2579,16 @@ static int em_invlpg(struct x86_emulate_ctxt *ctxt)
return X86EMUL_CONTINUE;
}
+static int em_clts(struct x86_emulate_ctxt *ctxt)
+{
+ ulong cr0;
+
+ cr0 = ctxt->ops->get_cr(ctxt, 0);
+ cr0 &= ~X86_CR0_TS;
+ ctxt->ops->set_cr(ctxt, 0, cr0);
+ return X86EMUL_CONTINUE;
+}
+
static bool valid_cr(int nr)
{
switch (nr) {
@@ -4079,7 +4089,7 @@ twobyte_insn:
rc = emulate_syscall(ctxt, ops);
break;
case 0x06:
- emulate_clts(ctxt->vcpu);
+ rc = em_clts(ctxt);
break;
case 0x09: /* wbinvd */
kvm_emulate_wbinvd(ctxt->vcpu);
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 7cd3a3b491de..a9e83862feb8 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -4153,13 +4153,6 @@ int kvm_emulate_wbinvd(struct kvm_vcpu *vcpu)
}
EXPORT_SYMBOL_GPL(kvm_emulate_wbinvd);
-int emulate_clts(struct kvm_vcpu *vcpu)
-{
- kvm_x86_ops->set_cr0(vcpu, kvm_read_cr0_bits(vcpu, ~X86_CR0_TS));
- kvm_x86_ops->fpu_activate(vcpu);
- return X86EMUL_CONTINUE;
-}
-
int emulator_get_dr(struct x86_emulate_ctxt *ctxt, int dr, unsigned long *dest)
{
return _kvm_get_dr(emul_to_vcpu(ctxt), dr, dest);
--
GitLab