[PATCH 30/41] KVM: SVM: forbid guest to execute monitor/mwait

Avi Kivity
2007-04-01T14:35:27Z

From: Joerg Roedel <joerg.roedel-5C7GfCeVMHo@public.gmane.org>

This patch forbids the guest to execute monitor/mwait instructions on
SVM. This is necessary because the guest can execute these instructions
if they are available even if the kvm cpuid doesn't report its
existence.

Signed-off-by: Joerg Roedel <joerg.roedel-5C7GfCeVMHo@public.gmane.org>
Signed-off-by: Avi Kivity <avi-atKUWr5tajBWk0Htik3J/w@public.gmane.org>
---
drivers/kvm/svm.c | 6 +++++-
drivers/kvm/svm.h | 6 ++++++
2 files changed, 11 insertions(+), 1 deletions(-)

diff --git a/drivers/kvm/svm.c b/drivers/kvm/svm.c
index ddc0505..0542d33 100644
--- a/drivers/kvm/svm.c
+++ b/drivers/kvm/svm.c
@@ -511,7 +511,9 @@ static void init_vmcb(struct vmcb *vmcb)
(1ULL << INTERCEPT_VMSAVE) |
(1ULL << INTERCEPT_STGI) |
(1ULL << INTERCEPT_CLGI) |
- (1ULL << INTERCEPT_SKINIT);
+ (1ULL << INTERCEPT_SKINIT) |
+ (1ULL << INTERCEPT_MONITOR) |
+ (1ULL << INTERCEPT_MWAIT);

control->iopm_base_pa = iopm_base;
control->msrpm_base_pa = msrpm_base;
@@ -1292,6 +1294,8 @@ static int (*svm_exit_handlers[])(struct kvm_vcpu *vcpu,
[SVM_EXIT_STGI] = invalid_op_interception,
[SVM_EXIT_CLGI] = invalid_op_interception,
[SVM_EXIT_SKINIT] = invalid_op_interception,
+ [SVM_EXIT_MONITOR] = invalid_op_interception,
+ [SVM_EXIT_MWAIT] = invalid_op_interception,
};

diff --git a/drivers/kvm/svm.h b/drivers/kvm/svm.h
index df731c3..5e93814 100644
--- a/drivers/kvm/svm.h
+++ b/drivers/kvm/svm.h
@@ -44,6 +44,9 @@ enum {
INTERCEPT_RDTSCP,
INTERCEPT_ICEBP,
INTERCEPT_WBINVD,
+ INTERCEPT_MONITOR,
+ INTERCEPT_MWAIT,
+ INTERCEPT_MWAIT_COND,
};

@@ -298,6 +301,9 @@ struct __attribute__ ((__packed__)) vmcb {
#define SVM_EXIT_RDTSCP 0x087
#define SVM_EXIT_ICEBP 0x088
#define SVM_EXIT_WBINVD 0x089
+#define SVM_EXIT_MONITOR 0x08a
+#define SVM_EXIT_MWAIT 0x08b
+#define SVM_EXIT_MWAIT_COND 0x08c
#define SVM_EXIT_NPF 0x400

#define SVM_EXIT_ERR -1