KVM: x86: INIT and reset sequences are different
x86 architecture defines differences between the reset and INIT sequences.
INIT does not initialize the FPU (including MMX, XMM, YMM, etc.), TSC, PMU,
MSRs (in general), MTRRs machine-check, APIC ID, APIC arbitration ID and BSP.
References (from Intel SDM):
"If the MP protocol has completed and a BSP is chosen, subsequent INITs (either
to a specific processor or system wide) do not cause the MP protocol to be
repeated." [8.4.2: MP Initialization Protocol Requirements and Restrictions]
[Table 9-1. IA-32 Processor States Following Power-up, Reset, or INIT]
"If the processor is reset by asserting the INIT# pin, the x87 FPU state is not
changed." [9.2: X87 FPU INITIALIZATION]
"The state of the local APIC following an INIT reset is the same as it is after
a power-up or hardware reset, except that the APIC ID and arbitration ID
registers are not affected." [10.4.7.3: Local APIC State After an INIT Reset
("Wait-for-SIPI" State)]
Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Message-Id: <1428924848-28212-1-git-send-email-namit@cs.technion.ac.il>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index f80ad59..3a19e30 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -711,7 +711,7 @@
/* Create, but do not attach this VCPU */
struct kvm_vcpu *(*vcpu_create)(struct kvm *kvm, unsigned id);
void (*vcpu_free)(struct kvm_vcpu *vcpu);
- void (*vcpu_reset)(struct kvm_vcpu *vcpu);
+ void (*vcpu_reset)(struct kvm_vcpu *vcpu, bool init_event);
void (*prepare_guest_switch)(struct kvm_vcpu *vcpu);
void (*vcpu_load)(struct kvm_vcpu *vcpu, int cpu);
@@ -1001,7 +1001,7 @@
void kvm_inject_nmi(struct kvm_vcpu *vcpu);
-int fx_init(struct kvm_vcpu *vcpu);
+int fx_init(struct kvm_vcpu *vcpu, bool init_event);
void kvm_mmu_pte_write(struct kvm_vcpu *vcpu, gpa_t gpa,
const u8 *new, int bytes);
@@ -1145,7 +1145,7 @@
int kvm_cpu_has_interrupt(struct kvm_vcpu *vcpu);
int kvm_arch_interrupt_allowed(struct kvm_vcpu *vcpu);
int kvm_cpu_get_interrupt(struct kvm_vcpu *v);
-void kvm_vcpu_reset(struct kvm_vcpu *vcpu);
+void kvm_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event);
void kvm_vcpu_reload_apic_access_page(struct kvm_vcpu *vcpu);
void kvm_arch_mmu_notifier_invalidate_page(struct kvm *kvm,
unsigned long address);
diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
index 4071eb1..abf1653 100644
--- a/arch/x86/kvm/lapic.c
+++ b/arch/x86/kvm/lapic.c
@@ -1557,7 +1557,7 @@
}
-void kvm_lapic_reset(struct kvm_vcpu *vcpu)
+void kvm_lapic_reset(struct kvm_vcpu *vcpu, bool init_event)
{
struct kvm_lapic *apic;
int i;
@@ -1571,7 +1571,8 @@
/* Stop the timer in case it's a reset to an active apic */
hrtimer_cancel(&apic->lapic_timer.timer);
- kvm_apic_set_id(apic, vcpu->vcpu_id);
+ if (!init_event)
+ kvm_apic_set_id(apic, vcpu->vcpu_id);
kvm_apic_set_version(apic->vcpu);
for (i = 0; i < APIC_LVT_NUM; i++)
@@ -1713,7 +1714,7 @@
APIC_DEFAULT_PHYS_BASE | MSR_IA32_APICBASE_ENABLE);
static_key_slow_inc(&apic_sw_disabled.key); /* sw disabled at reset */
- kvm_lapic_reset(vcpu);
+ kvm_lapic_reset(vcpu, false);
kvm_iodevice_init(&apic->dev, &apic_mmio_ops);
return 0;
@@ -2047,8 +2048,8 @@
pe = xchg(&apic->pending_events, 0);
if (test_bit(KVM_APIC_INIT, &pe)) {
- kvm_lapic_reset(vcpu);
- kvm_vcpu_reset(vcpu);
+ kvm_lapic_reset(vcpu, true);
+ kvm_vcpu_reset(vcpu, true);
if (kvm_vcpu_is_bsp(apic->vcpu))
vcpu->arch.mp_state = KVM_MP_STATE_RUNNABLE;
else
diff --git a/arch/x86/kvm/lapic.h b/arch/x86/kvm/lapic.h
index 9d28383..793f761 100644
--- a/arch/x86/kvm/lapic.h
+++ b/arch/x86/kvm/lapic.h
@@ -48,7 +48,7 @@
int kvm_apic_accept_pic_intr(struct kvm_vcpu *vcpu);
int kvm_get_apic_interrupt(struct kvm_vcpu *vcpu);
void kvm_apic_accept_events(struct kvm_vcpu *vcpu);
-void kvm_lapic_reset(struct kvm_vcpu *vcpu);
+void kvm_lapic_reset(struct kvm_vcpu *vcpu, bool init_event);
u64 kvm_lapic_get_cr8(struct kvm_vcpu *vcpu);
void kvm_lapic_set_tpr(struct kvm_vcpu *vcpu, unsigned long cr8);
void kvm_lapic_set_eoi(struct kvm_vcpu *vcpu);
diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
index 46299da..b6ad0f9 100644
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -1082,7 +1082,7 @@
return target_tsc - tsc;
}
-static void init_vmcb(struct vcpu_svm *svm)
+static void init_vmcb(struct vcpu_svm *svm, bool init_event)
{
struct vmcb_control_area *control = &svm->vmcb->control;
struct vmcb_save_area *save = &svm->vmcb->save;
@@ -1153,17 +1153,17 @@
init_sys_seg(&save->ldtr, SEG_TYPE_LDT);
init_sys_seg(&save->tr, SEG_TYPE_BUSY_TSS16);
- svm_set_efer(&svm->vcpu, 0);
+ if (!init_event)
+ svm_set_efer(&svm->vcpu, 0);
save->dr6 = 0xffff0ff0;
kvm_set_rflags(&svm->vcpu, 2);
save->rip = 0x0000fff0;
svm->vcpu.arch.regs[VCPU_REGS_RIP] = save->rip;
/*
- * This is the guest-visible cr0 value.
* svm_set_cr0() sets PG and WP and clears NW and CD on save->cr0.
+ * It also updates the guest-visible cr0 value.
*/
- svm->vcpu.arch.cr0 = 0;
(void)kvm_set_cr0(&svm->vcpu, X86_CR0_NW | X86_CR0_CD | X86_CR0_ET);
save->cr4 = X86_CR4_PAE;
@@ -1195,13 +1195,19 @@
enable_gif(svm);
}
-static void svm_vcpu_reset(struct kvm_vcpu *vcpu)
+static void svm_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event)
{
struct vcpu_svm *svm = to_svm(vcpu);
u32 dummy;
u32 eax = 1;
- init_vmcb(svm);
+ if (!init_event) {
+ svm->vcpu.arch.apic_base = APIC_DEFAULT_PHYS_BASE |
+ MSR_IA32_APICBASE_ENABLE;
+ if (kvm_vcpu_is_reset_bsp(&svm->vcpu))
+ svm->vcpu.arch.apic_base |= MSR_IA32_APICBASE_BSP;
+ }
+ init_vmcb(svm, init_event);
kvm_cpuid(vcpu, &eax, &dummy, &dummy, &dummy);
kvm_register_write(vcpu, VCPU_REGS_RDX, eax);
@@ -1257,12 +1263,7 @@
clear_page(svm->vmcb);
svm->vmcb_pa = page_to_pfn(page) << PAGE_SHIFT;
svm->asid_generation = 0;
- init_vmcb(svm);
-
- svm->vcpu.arch.apic_base = APIC_DEFAULT_PHYS_BASE |
- MSR_IA32_APICBASE_ENABLE;
- if (kvm_vcpu_is_reset_bsp(&svm->vcpu))
- svm->vcpu.arch.apic_base |= MSR_IA32_APICBASE_BSP;
+ init_vmcb(svm, false);
svm_init_osvw(&svm->vcpu);
@@ -1884,7 +1885,7 @@
* so reinitialize it.
*/
clear_page(svm->vmcb);
- init_vmcb(svm);
+ init_vmcb(svm, false);
kvm_run->exit_reason = KVM_EXIT_SHUTDOWN;
return 0;
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index f7b6168..a694ff6 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -4708,22 +4708,27 @@
return 0;
}
-static void vmx_vcpu_reset(struct kvm_vcpu *vcpu)
+static void vmx_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event)
{
struct vcpu_vmx *vmx = to_vmx(vcpu);
struct msr_data apic_base_msr;
+ u64 cr0;
vmx->rmode.vm86_active = 0;
vmx->soft_vnmi_blocked = 0;
vmx->vcpu.arch.regs[VCPU_REGS_RDX] = get_rdx_init_val();
- kvm_set_cr8(&vmx->vcpu, 0);
- apic_base_msr.data = APIC_DEFAULT_PHYS_BASE | MSR_IA32_APICBASE_ENABLE;
- if (kvm_vcpu_is_reset_bsp(&vmx->vcpu))
- apic_base_msr.data |= MSR_IA32_APICBASE_BSP;
- apic_base_msr.host_initiated = true;
- kvm_set_apic_base(&vmx->vcpu, &apic_base_msr);
+ kvm_set_cr8(vcpu, 0);
+
+ if (!init_event) {
+ apic_base_msr.data = APIC_DEFAULT_PHYS_BASE |
+ MSR_IA32_APICBASE_ENABLE;
+ if (kvm_vcpu_is_reset_bsp(vcpu))
+ apic_base_msr.data |= MSR_IA32_APICBASE_BSP;
+ apic_base_msr.host_initiated = true;
+ kvm_set_apic_base(vcpu, &apic_base_msr);
+ }
vmx_segment_cache_clear(vmx);
@@ -4747,9 +4752,12 @@
vmcs_write32(GUEST_LDTR_LIMIT, 0xffff);
vmcs_write32(GUEST_LDTR_AR_BYTES, 0x00082);
- vmcs_write32(GUEST_SYSENTER_CS, 0);
- vmcs_writel(GUEST_SYSENTER_ESP, 0);
- vmcs_writel(GUEST_SYSENTER_EIP, 0);
+ if (!init_event) {
+ vmcs_write32(GUEST_SYSENTER_CS, 0);
+ vmcs_writel(GUEST_SYSENTER_ESP, 0);
+ vmcs_writel(GUEST_SYSENTER_EIP, 0);
+ vmcs_write64(GUEST_IA32_DEBUGCTL, 0);
+ }
vmcs_writel(GUEST_RFLAGS, 0x02);
kvm_rip_write(vcpu, 0xfff0);
@@ -4764,18 +4772,15 @@
vmcs_write32(GUEST_INTERRUPTIBILITY_INFO, 0);
vmcs_write32(GUEST_PENDING_DBG_EXCEPTIONS, 0);
- /* Special registers */
- vmcs_write64(GUEST_IA32_DEBUGCTL, 0);
-
setup_msrs(vmx);
vmcs_write32(VM_ENTRY_INTR_INFO_FIELD, 0); /* 22.2.1 */
- if (cpu_has_vmx_tpr_shadow()) {
+ if (cpu_has_vmx_tpr_shadow() && !init_event) {
vmcs_write64(VIRTUAL_APIC_PAGE_ADDR, 0);
- if (vm_need_tpr_shadow(vmx->vcpu.kvm))
+ if (vm_need_tpr_shadow(vcpu->kvm))
vmcs_write64(VIRTUAL_APIC_PAGE_ADDR,
- __pa(vmx->vcpu.arch.apic->regs));
+ __pa(vcpu->arch.apic->regs));
vmcs_write32(TPR_THRESHOLD, 0);
}
@@ -4787,12 +4792,14 @@
if (vmx->vpid != 0)
vmcs_write16(VIRTUAL_PROCESSOR_ID, vmx->vpid);
- vmx->vcpu.arch.cr0 = X86_CR0_NW | X86_CR0_CD | X86_CR0_ET;
- vmx_set_cr0(&vmx->vcpu, kvm_read_cr0(vcpu)); /* enter rmode */
- vmx_set_cr4(&vmx->vcpu, 0);
- vmx_set_efer(&vmx->vcpu, 0);
- vmx_fpu_activate(&vmx->vcpu);
- update_exception_bitmap(&vmx->vcpu);
+ cr0 = X86_CR0_NW | X86_CR0_CD | X86_CR0_ET;
+ vmx_set_cr0(vcpu, cr0); /* enter rmode */
+ vmx->vcpu.arch.cr0 = cr0;
+ vmx_set_cr4(vcpu, 0);
+ if (!init_event)
+ vmx_set_efer(vcpu, 0);
+ vmx_fpu_activate(vcpu);
+ update_exception_bitmap(vcpu);
vpid_sync_context(vmx);
}
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 0435b65..755a79f 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -7033,7 +7033,7 @@
return 0;
}
-int fx_init(struct kvm_vcpu *vcpu)
+int fx_init(struct kvm_vcpu *vcpu, bool init_event)
{
int err;
@@ -7041,7 +7041,9 @@
if (err)
return err;
- fpu_finit(&vcpu->arch.guest_fpu);
+ if (!init_event)
+ fpu_finit(&vcpu->arch.guest_fpu);
+
if (cpu_has_xsaves)
vcpu->arch.guest_fpu.state->xsave.xsave_hdr.xcomp_bv =
host_xcr0 | XSTATE_COMPACTION_ENABLED;
@@ -7121,7 +7123,7 @@
r = vcpu_load(vcpu);
if (r)
return r;
- kvm_vcpu_reset(vcpu);
+ kvm_vcpu_reset(vcpu, false);
kvm_mmu_setup(vcpu);
vcpu_put(vcpu);
@@ -7159,7 +7161,7 @@
kvm_x86_ops->vcpu_free(vcpu);
}
-void kvm_vcpu_reset(struct kvm_vcpu *vcpu)
+void kvm_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event)
{
atomic_set(&vcpu->arch.nmi_queued, 0);
vcpu->arch.nmi_pending = 0;
@@ -7186,13 +7188,14 @@
kvm_async_pf_hash_reset(vcpu);
vcpu->arch.apf.halted = false;
- kvm_pmu_reset(vcpu);
+ if (!init_event)
+ kvm_pmu_reset(vcpu);
memset(vcpu->arch.regs, 0, sizeof(vcpu->arch.regs));
vcpu->arch.regs_avail = ~0;
vcpu->arch.regs_dirty = ~0;
- kvm_x86_ops->vcpu_reset(vcpu);
+ kvm_x86_ops->vcpu_reset(vcpu, init_event);
}
void kvm_vcpu_deliver_sipi_vector(struct kvm_vcpu *vcpu, u8 vector)
@@ -7381,7 +7384,7 @@
goto fail_free_mce_banks;
}
- r = fx_init(vcpu);
+ r = fx_init(vcpu, false);
if (r)
goto fail_free_wbinvd_dirty_mask;