KVM: x86: Make register state after reset conform to specification

VMX behaves now as SVM wrt to FPU initialization. Code has been moved to
generic code path. General-purpose registers are now cleared on reset and
INIT.  SVM code properly initializes EDX.

Signed-off-by: Julian Stecklina <jsteckli@os.inf.tu-dresden.de>
Signed-off-by: Gleb Natapov <gleb@redhat.com>

4 files changed, 17 insertions, 16 deletions

diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c
index 52f6166ef92c..a20ecb5b6cbf 100644
--- a/arch/x86/kvm/cpuid.c
+++ b/arch/x86/kvm/cpuid.c
@@ -661,6 +661,7 @@ void kvm_cpuid(struct kvm_vcpu *vcpu, u32 *eax, u32 *ebx, u32 *ecx, u32 *edx)
         } else
                 *eax = *ebx = *ecx = *edx = 0;
 }
+EXPORT_SYMBOL_GPL(kvm_cpuid);
 
 void kvm_emulate_cpuid(struct kvm_vcpu *vcpu)
 {
diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
index dcb79527e7aa..d29d3cd1c156 100644
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -20,6 +20,7 @@
 #include "mmu.h"
 #include "kvm_cache_regs.h"
 #include "x86.h"
+#include "cpuid.h"
 
 #include <linux/module.h>
 #include <linux/mod_devicetable.h>
@@ -1193,6 +1194,8 @@ static void init_vmcb(struct vcpu_svm *svm)
 static int svm_vcpu_reset(struct kvm_vcpu *vcpu)
 {
         struct vcpu_svm *svm = to_svm(vcpu);
+        u32 dummy;
+        u32 eax = 1;
 
         init_vmcb(svm);
 
@@ -1201,8 +1204,9 @@ static int svm_vcpu_reset(struct kvm_vcpu *vcpu)
                 svm->vmcb->save.cs.base = svm->vcpu.arch.sipi_vector << 12;
                 svm->vmcb->save.cs.selector = svm->vcpu.arch.sipi_vector << 8;
         }
-        vcpu->arch.regs_avail = ~0;
-        vcpu->arch.regs_dirty = ~0;
+
+        kvm_cpuid(vcpu, &eax, &dummy, &dummy, &dummy);
+        kvm_register_write(vcpu, VCPU_REGS_RDX, eax);
 
         return 0;
 }
@@ -1259,10 +1263,6 @@ static struct kvm_vcpu *svm_create_vcpu(struct kvm *kvm, unsigned int id)
         svm->asid_generation = 0;
         init_vmcb(svm);
 
-        err = fx_init(&svm->vcpu);
-        if (err)
-                goto free_page4;
-
         svm->vcpu.arch.apic_base = 0xfee00000 | MSR_IA32_APICBASE_ENABLE;
         if (kvm_vcpu_is_bsp(&svm->vcpu))
                 svm->vcpu.arch.apic_base |= MSR_IA32_APICBASE_BSP;
@@ -1271,8 +1271,6 @@ static struct kvm_vcpu *svm_create_vcpu(struct kvm *kvm, unsigned int id)
 
         return &svm->vcpu;
 
-free_page4:
-        __free_page(hsave_page);
 free_page3:
         __free_pages(nested_msrpm_pages, MSRPM_ALLOC_ORDER);
 free_page2:
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index 32485d8d05d4..94833e2fe78c 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -3918,8 +3918,6 @@ static int vmx_vcpu_reset(struct kvm_vcpu *vcpu)
         u64 msr;
         int ret;
 
-        vcpu->arch.regs_avail = ~((1 << VCPU_REGS_RIP) | (1 << VCPU_REGS_RSP));
-
         vmx->rmode.vm86_active = 0;
 
         vmx->soft_vnmi_blocked = 0;
@@ -3931,10 +3929,6 @@ static int vmx_vcpu_reset(struct kvm_vcpu *vcpu)
                 msr |= MSR_IA32_APICBASE_BSP;
         kvm_set_apic_base(&vmx->vcpu, msr);
 
-        ret = fx_init(&vmx->vcpu);
-        if (ret != 0)
-                goto out;
-
         vmx_segment_cache_clear(vmx);
 
         seg_setup(VCPU_SREG_CS);
@@ -3975,7 +3969,6 @@ static int vmx_vcpu_reset(struct kvm_vcpu *vcpu)
                 kvm_rip_write(vcpu, 0xfff0);
         else
                 kvm_rip_write(vcpu, 0);
-        kvm_register_write(vcpu, VCPU_REGS_RSP, 0);
 
         vmcs_writel(GUEST_GDTR_BASE, 0);
         vmcs_write32(GUEST_GDTR_LIMIT, 0xffff);
@@ -4025,7 +4018,6 @@ static int vmx_vcpu_reset(struct kvm_vcpu *vcpu)
         /* HACK: Don't enable emulation on guest boot/reset */
         vmx->emulation_required = 0;
 
-out:
         return ret;
 }
 
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 3bdaf298b8c7..57c76e86e9bd 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -6461,6 +6461,10 @@ static int kvm_vcpu_reset(struct kvm_vcpu *vcpu)
 
         kvm_pmu_reset(vcpu);
 
+        memset(vcpu->arch.regs, 0, sizeof(vcpu->arch.regs));
+        vcpu->arch.regs_avail = ~0;
+        vcpu->arch.regs_dirty = ~0;
+
         return kvm_x86_ops->vcpu_reset(vcpu);
 }
 
@@ -6629,11 +6633,17 @@ int kvm_arch_vcpu_init(struct kvm_vcpu *vcpu)
         if (!zalloc_cpumask_var(&vcpu->arch.wbinvd_dirty_mask, GFP_KERNEL))
                 goto fail_free_mce_banks;
 
+        r = fx_init(vcpu);
+        if (r)
+                goto fail_free_wbinvd_dirty_mask;
+
         vcpu->arch.ia32_tsc_adjust_msr = 0x0;
         kvm_async_pf_hash_reset(vcpu);
         kvm_pmu_init(vcpu);
 
         return 0;
+fail_free_wbinvd_dirty_mask:
+        free_cpumask_var(vcpu->arch.wbinvd_dirty_mask);
 fail_free_mce_banks:
         kfree(vcpu->arch.mce_banks);
 fail_free_lapic: