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/vmx.c b/arch/x86/kvm/vmx.c
index 3606154..45ffa32 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -2220,15 +2220,17 @@
* Returns 0 on success, non-0 otherwise.
* Assumes vcpu_load() was already called.
*/
-static int vmx_set_msr(struct kvm_vcpu *vcpu, u32 msr_index, u64 data)
+static int vmx_set_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
{
struct vcpu_vmx *vmx = to_vmx(vcpu);
struct shared_msr_entry *msr;
int ret = 0;
+ u32 msr_index = msr_info->index;
+ u64 data = msr_info->data;
switch (msr_index) {
case MSR_EFER:
- ret = kvm_set_msr_common(vcpu, msr_index, data);
+ ret = kvm_set_msr_common(vcpu, msr_info);
break;
#ifdef CONFIG_X86_64
case MSR_FS_BASE:
@@ -2254,7 +2256,7 @@
vmcs_writel(GUEST_SYSENTER_ESP, data);
break;
case MSR_IA32_TSC:
- kvm_write_tsc(vcpu, data);
+ kvm_write_tsc(vcpu, msr_info);
break;
case MSR_IA32_CR_PAT:
if (vmcs_config.vmentry_ctrl & VM_ENTRY_LOAD_IA32_PAT) {
@@ -2262,7 +2264,7 @@
vcpu->arch.pat = data;
break;
}
- ret = kvm_set_msr_common(vcpu, msr_index, data);
+ ret = kvm_set_msr_common(vcpu, msr_info);
break;
case MSR_TSC_AUX:
if (!vmx->rdtscp_enabled)
@@ -2285,7 +2287,7 @@
}
break;
}
- ret = kvm_set_msr_common(vcpu, msr_index, data);
+ ret = kvm_set_msr_common(vcpu, msr_info);
}
return ret;
@@ -4648,11 +4650,15 @@
static int handle_wrmsr(struct kvm_vcpu *vcpu)
{
+ struct msr_data msr;
u32 ecx = vcpu->arch.regs[VCPU_REGS_RCX];
u64 data = (vcpu->arch.regs[VCPU_REGS_RAX] & -1u)
| ((u64)(vcpu->arch.regs[VCPU_REGS_RDX] & -1u) << 32);
- if (vmx_set_msr(vcpu, ecx, data) != 0) {
+ msr.data = data;
+ msr.index = ecx;
+ msr.host_initiated = false;
+ if (vmx_set_msr(vcpu, &msr) != 0) {
trace_kvm_msr_write_ex(ecx, data);
kvm_inject_gp(vcpu, 0);
return 1;