KVM: x86: Add code to track call origin for msr assignment
In order to track who initiated the call (host or guest) to modify an msr
value I have changed function call parameters along the call path. The
specific change is to add a struct pointer parameter that points to (index,
data, caller) information rather than having this information passed as
individual parameters.
The initial use for this capability is for updating the IA32_TSC_ADJUST msr
while setting the tsc value. It is anticipated that this capability is
useful for other tasks.
Signed-off-by: Will Auld <will.auld@intel.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index fd76621..95f6613 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -890,9 +890,9 @@
* Returns 0 on success, non-0 otherwise.
* Assumes vcpu_load() was already called.
*/
-int kvm_set_msr(struct kvm_vcpu *vcpu, u32 msr_index, u64 data)
+int kvm_set_msr(struct kvm_vcpu *vcpu, struct msr_data *msr)
{
- return kvm_x86_ops->set_msr(vcpu, msr_index, data);
+ return kvm_x86_ops->set_msr(vcpu, msr);
}
/*
@@ -900,7 +900,12 @@
*/
static int do_set_msr(struct kvm_vcpu *vcpu, unsigned index, u64 *data)
{
- return kvm_set_msr(vcpu, index, *data);
+ struct msr_data msr;
+
+ msr.data = *data;
+ msr.index = index;
+ msr.host_initiated = true;
+ return kvm_set_msr(vcpu, &msr);
}
#ifdef CONFIG_X86_64
@@ -1130,13 +1135,14 @@
#endif
}
-void kvm_write_tsc(struct kvm_vcpu *vcpu, u64 data)
+void kvm_write_tsc(struct kvm_vcpu *vcpu, struct msr_data *msr)
{
struct kvm *kvm = vcpu->kvm;
u64 offset, ns, elapsed;
unsigned long flags;
s64 usdiff;
bool matched;
+ u64 data = msr->data;
raw_spin_lock_irqsave(&kvm->arch.tsc_write_lock, flags);
offset = kvm_x86_ops->compute_tsc_offset(vcpu, data);
@@ -1857,9 +1863,11 @@
&vcpu->arch.st.steal, sizeof(struct kvm_steal_time));
}
-int kvm_set_msr_common(struct kvm_vcpu *vcpu, u32 msr, u64 data)
+int kvm_set_msr_common(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
{
bool pr = false;
+ u32 msr = msr_info->index;
+ u64 data = msr_info->data;
switch (msr) {
case MSR_EFER:
@@ -4531,7 +4539,12 @@
static int emulator_set_msr(struct x86_emulate_ctxt *ctxt,
u32 msr_index, u64 data)
{
- return kvm_set_msr(emul_to_vcpu(ctxt), msr_index, data);
+ struct msr_data msr;
+
+ msr.data = data;
+ msr.index = msr_index;
+ msr.host_initiated = false;
+ return kvm_set_msr(emul_to_vcpu(ctxt), &msr);
}
static int emulator_read_pmc(struct x86_emulate_ctxt *ctxt,
@@ -6375,11 +6388,15 @@
int kvm_arch_vcpu_postcreate(struct kvm_vcpu *vcpu)
{
int r;
+ struct msr_data msr;
r = vcpu_load(vcpu);
if (r)
return r;
- kvm_write_tsc(vcpu, 0);
+ msr.data = 0x0;
+ msr.index = MSR_IA32_TSC;
+ msr.host_initiated = true;
+ kvm_write_tsc(vcpu, &msr);
vcpu_put(vcpu);
return r;