KVM: x86: Move IA32_XSS-swapping on VM-entry/VM-exit to common x86 code

Hoist the vendor-specific code related to loading the hardware IA32_XSS
MSR with guest/host values on VM-entry/VM-exit to common x86 code.

Reviewed-by: Jim Mattson <jmattson@google.com>
Signed-off-by: Aaron Lewis <aaronlewis@google.com>
Change-Id: Ic6e3430833955b98eb9b79ae6715cf2a3fdd6d82
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
index fa29125193fec5f6a0c9d94ff010510bac5a46ee..77429fa3874824955dfd94091074cbcb4967758c 100644 (file)
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -116,8 +116,6 @@ MODULE_DEVICE_TABLE(x86cpu, svm_cpu_id);
 
 static bool erratum_383_found __read_mostly;
 
-static u64 __read_mostly host_xss;
-
 static const u32 host_save_user_msrs[] = {
 #ifdef CONFIG_X86_64
        MSR_STAR, MSR_LSTAR, MSR_CSTAR, MSR_SYSCALL_MASK, MSR_KERNEL_GS_BASE,
@@ -1411,9 +1409,6 @@ static __init int svm_hardware_setup(void)
                        pr_info("Virtual GIF supported\n");
        }
 
-       if (boot_cpu_has(X86_FEATURE_XSAVES))
-               rdmsrl(MSR_IA32_XSS, host_xss);
-
        return 0;
 
 err:
@@ -5603,22 +5598,6 @@ static void svm_cancel_injection(struct kvm_vcpu *vcpu)
        svm_complete_interrupts(svm);
 }
 
-static void svm_load_guest_xss(struct kvm_vcpu *vcpu)
-{
-       if (kvm_read_cr4_bits(vcpu, X86_CR4_OSXSAVE) &&
-           vcpu->arch.xsaves_enabled &&
-           vcpu->arch.ia32_xss != host_xss)
-               wrmsrl(MSR_IA32_XSS, vcpu->arch.ia32_xss);
-}
-
-static void svm_load_host_xss(struct kvm_vcpu *vcpu)
-{
-       if (kvm_read_cr4_bits(vcpu, X86_CR4_OSXSAVE) &&
-           vcpu->arch.xsaves_enabled &&
-           vcpu->arch.ia32_xss != host_xss)
-               wrmsrl(MSR_IA32_XSS, host_xss);
-}
-
 static void svm_vcpu_run(struct kvm_vcpu *vcpu)
 {
        struct vcpu_svm *svm = to_svm(vcpu);
@@ -5657,8 +5636,7 @@ static void svm_vcpu_run(struct kvm_vcpu *vcpu)
        svm->vmcb->save.cr2 = vcpu->arch.cr2;
 
        clgi();
-       kvm_load_guest_xcr0(vcpu);
-       svm_load_guest_xss(vcpu);
+       kvm_load_guest_xsave_state(vcpu);
 
        if (lapic_in_kernel(vcpu) &&
                vcpu->arch.apic->lapic_timer.timer_advance_ns)
@@ -5808,8 +5786,7 @@ static void svm_vcpu_run(struct kvm_vcpu *vcpu)
        if (unlikely(svm->vmcb->control.exit_code == SVM_EXIT_NMI))
                kvm_before_interrupt(&svm->vcpu);
 
-       svm_load_host_xss(vcpu);
-       kvm_put_guest_xcr0(vcpu);
+       kvm_load_host_xsave_state(vcpu);
        stgi();
 
        /* Any pending NMI will happen here */

diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index aee6f1a9d252662de906b4ebb005d7474ef97919..d06140bdb3adc58c3b65b82b43325431d9986ac9 100644 (file)
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -106,8 +106,6 @@ module_param(enable_apicv, bool, S_IRUGO);
 static bool __read_mostly nested = 1;
 module_param(nested, bool, S_IRUGO);
 
-static u64 __read_mostly host_xss;
-
 bool __read_mostly enable_pml = 1;
 module_param_named(pml, enable_pml, bool, S_IRUGO);
 
@@ -6466,22 +6464,6 @@ void vmx_update_host_rsp(struct vcpu_vmx *vmx, unsigned long host_rsp)
        }
 }
 
-static void vmx_load_guest_xss(struct kvm_vcpu *vcpu)
-{
-       if (kvm_read_cr4_bits(vcpu, X86_CR4_OSXSAVE) &&
-           vcpu->arch.xsaves_enabled &&
-           vcpu->arch.ia32_xss != host_xss)
-               wrmsrl(MSR_IA32_XSS, vcpu->arch.ia32_xss);
-}
-
-static void vmx_load_host_xss(struct kvm_vcpu *vcpu)
-{
-       if (kvm_read_cr4_bits(vcpu, X86_CR4_OSXSAVE) &&
-           vcpu->arch.xsaves_enabled &&
-           vcpu->arch.ia32_xss != host_xss)
-               wrmsrl(MSR_IA32_XSS, host_xss);
-}
-
 bool __vmx_vcpu_run(struct vcpu_vmx *vmx, unsigned long *regs, bool launched);
 
 static void vmx_vcpu_run(struct kvm_vcpu *vcpu)
@@ -6532,8 +6514,7 @@ static void vmx_vcpu_run(struct kvm_vcpu *vcpu)
        if (vcpu->guest_debug & KVM_GUESTDBG_SINGLESTEP)
                vmx_set_interrupt_shadow(vcpu, 0);
 
-       kvm_load_guest_xcr0(vcpu);
-       vmx_load_guest_xss(vcpu);
+       kvm_load_guest_xsave_state(vcpu);
 
        if (static_cpu_has(X86_FEATURE_PKU) &&
            kvm_read_cr4_bits(vcpu, X86_CR4_PKE) &&
@@ -6640,8 +6621,7 @@ static void vmx_vcpu_run(struct kvm_vcpu *vcpu)
                        __write_pkru(vmx->host_pkru);
        }
 
-       vmx_load_host_xss(vcpu);
-       kvm_put_guest_xcr0(vcpu);
+       kvm_load_host_xsave_state(vcpu);
 
        vmx->nested.nested_run_pending = 0;
        vmx->idt_vectoring_info = 0;
@@ -7611,9 +7591,6 @@ static __init int hardware_setup(void)
                WARN_ONCE(host_bndcfgs, "KVM: BNDCFGS in host will be lost");
        }
 
-       if (boot_cpu_has(X86_FEATURE_XSAVES))
-               rdmsrl(MSR_IA32_XSS, host_xss);
-
        if (!cpu_has_vmx_vpid() || !cpu_has_vmx_invvpid() ||
            !(cpu_has_vmx_invvpid_single() || cpu_has_vmx_invvpid_global()))
                enable_vpid = 0;

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 7141f81141a24d282a1e374145c46b0db3ddd70b..1ebe13493241a37c34ad0f0b362e30324663e422 100644 (file)
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -176,6 +176,8 @@ struct kvm_shared_msrs {
 static struct kvm_shared_msrs_global __read_mostly shared_msrs_global;
 static struct kvm_shared_msrs __percpu *shared_msrs;
 
+static u64 __read_mostly host_xss;
+
 struct kvm_stats_debugfs_item debugfs_entries[] = {
        { "pf_fixed", VCPU_STAT(pf_fixed) },
        { "pf_guest", VCPU_STAT(pf_guest) },
@@ -808,21 +810,34 @@ void kvm_lmsw(struct kvm_vcpu *vcpu, unsigned long msw)
 }
 EXPORT_SYMBOL_GPL(kvm_lmsw);
 
-void kvm_load_guest_xcr0(struct kvm_vcpu *vcpu)
+void kvm_load_guest_xsave_state(struct kvm_vcpu *vcpu)
 {
-       if (kvm_read_cr4_bits(vcpu, X86_CR4_OSXSAVE) &&
-           vcpu->arch.xcr0 != host_xcr0)
-               xsetbv(XCR_XFEATURE_ENABLED_MASK, vcpu->arch.xcr0);
+       if (kvm_read_cr4_bits(vcpu, X86_CR4_OSXSAVE)) {
+
+               if (vcpu->arch.xcr0 != host_xcr0)
+                       xsetbv(XCR_XFEATURE_ENABLED_MASK, vcpu->arch.xcr0);
+
+               if (vcpu->arch.xsaves_enabled &&
+                   vcpu->arch.ia32_xss != host_xss)
+                       wrmsrl(MSR_IA32_XSS, vcpu->arch.ia32_xss);
+       }
 }
-EXPORT_SYMBOL_GPL(kvm_load_guest_xcr0);
+EXPORT_SYMBOL_GPL(kvm_load_guest_xsave_state);
 
-void kvm_put_guest_xcr0(struct kvm_vcpu *vcpu)
+void kvm_load_host_xsave_state(struct kvm_vcpu *vcpu)
 {
-       if (kvm_read_cr4_bits(vcpu, X86_CR4_OSXSAVE) &&
-           vcpu->arch.xcr0 != host_xcr0)
-               xsetbv(XCR_XFEATURE_ENABLED_MASK, host_xcr0);
+       if (kvm_read_cr4_bits(vcpu, X86_CR4_OSXSAVE)) {
+
+               if (vcpu->arch.xcr0 != host_xcr0)
+                       xsetbv(XCR_XFEATURE_ENABLED_MASK, host_xcr0);
+
+               if (vcpu->arch.xsaves_enabled &&
+                   vcpu->arch.ia32_xss != host_xss)
+                       wrmsrl(MSR_IA32_XSS, host_xss);
+       }
+
 }
-EXPORT_SYMBOL_GPL(kvm_put_guest_xcr0);
+EXPORT_SYMBOL_GPL(kvm_load_host_xsave_state);
 
 static int __kvm_set_xcr(struct kvm_vcpu *vcpu, u32 index, u64 xcr)
 {
@@ -9278,6 +9293,9 @@ int kvm_arch_hardware_setup(void)
                kvm_default_tsc_scaling_ratio = 1ULL << kvm_tsc_scaling_ratio_frac_bits;
        }
 
+       if (boot_cpu_has(X86_FEATURE_XSAVES))
+               rdmsrl(MSR_IA32_XSS, host_xss);
+
        kvm_init_msr_list();
        return 0;
 }

diff --git a/arch/x86/kvm/x86.h b/arch/x86/kvm/x86.h
index 45d82b8277e55c5d88f83fb4acdcbaa256f7d897..2b0805012e3c84bc0c320e6da6298635dad66dba 100644 (file)
--- a/arch/x86/kvm/x86.h
+++ b/arch/x86/kvm/x86.h
@@ -364,7 +364,7 @@ static inline bool kvm_pat_valid(u64 data)
        return (data | ((data & 0x0202020202020202ull) << 1)) == data;
 }
 
-void kvm_load_guest_xcr0(struct kvm_vcpu *vcpu);
-void kvm_put_guest_xcr0(struct kvm_vcpu *vcpu);
+void kvm_load_guest_xsave_state(struct kvm_vcpu *vcpu);
+void kvm_load_host_xsave_state(struct kvm_vcpu *vcpu);
 
 #endif