From 1edce0a9eb239b7a2768d10cf7d21dd83e269d5b Mon Sep 17 00:00:00 2001 From: Sean Christopherson Date: Thu, 5 Sep 2019 14:22:55 -0700 Subject: KVM: x86: Add kvm_emulate_{rd,wr}msr() to consolidate VXM/SVM code Move RDMSR and WRMSR emulation into common x86 code to consolidate nearly identical SVM and VMX code. Note, consolidating RDMSR introduces an extra indirect call, i.e. retpoline, due to reaching {svm,vmx}_get_msr() via kvm_x86_ops, but a guest kernel likely has bigger problems if increasing the latency of RDMSR VM-Exits by ~70 cycles has a measurable impact on overall VM performance. E.g. the only recurring RDMSR VM-Exits (after booting) on my system running Linux 5.2 in the guest are for MSR_IA32_TSC_ADJUST via arch_cpu_idle_enter(). No functional change intended. Signed-off-by: Sean Christopherson Signed-off-by: Paolo Bonzini --- arch/x86/kvm/vmx/vmx.c | 29 ++--------------------------- 1 file changed, 2 insertions(+), 27 deletions(-) (limited to 'arch/x86/kvm/vmx') diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c index c8af21ce52a7..024cb9bf5ad3 100644 --- a/arch/x86/kvm/vmx/vmx.c +++ b/arch/x86/kvm/vmx/vmx.c @@ -4866,37 +4866,12 @@ static int handle_cpuid(struct kvm_vcpu *vcpu) static int handle_rdmsr(struct kvm_vcpu *vcpu) { - u32 ecx = kvm_rcx_read(vcpu); - struct msr_data msr_info; - - msr_info.index = ecx; - msr_info.host_initiated = false; - if (vmx_get_msr(vcpu, &msr_info)) { - trace_kvm_msr_read_ex(ecx); - kvm_inject_gp(vcpu, 0); - return 1; - } - - trace_kvm_msr_read(ecx, msr_info.data); - - kvm_rax_write(vcpu, msr_info.data & -1u); - kvm_rdx_write(vcpu, (msr_info.data >> 32) & -1u); - return kvm_skip_emulated_instruction(vcpu); + return kvm_emulate_rdmsr(vcpu); } static int handle_wrmsr(struct kvm_vcpu *vcpu) { - u32 ecx = kvm_rcx_read(vcpu); - u64 data = kvm_read_edx_eax(vcpu); - - if (kvm_set_msr(vcpu, ecx, data) != 0) { - trace_kvm_msr_write_ex(ecx, data); - kvm_inject_gp(vcpu, 0); - return 1; - } - - trace_kvm_msr_write(ecx, data); - return kvm_skip_emulated_instruction(vcpu); + return kvm_emulate_wrmsr(vcpu); } static int handle_tpr_below_threshold(struct kvm_vcpu *vcpu) -- cgit v1.2.3