arch/x86/kvm/svm.c

/*
 * Kernel-based Virtual Machine driver for Linux
 *
 * AMD SVM support
 *
 * Copyright (C) 2006 Qumranet, Inc.
 * Copyright 2010 Red Hat, Inc. and/or its affiliates.
 *
 * Authors:
 *   Yaniv Kamay  <yaniv@qumranet.com>
 *   Avi Kivity   <avi@qumranet.com>
 *
 * This work is licensed under the terms of the GNU GPL, version 2.  See
 * the COPYING file in the top-level directory.
 *
 */
#include <linux/kvm_host.h>

#include "irq.h"
#include "mmu.h"
#include "kvm_cache_regs.h"
#include "x86.h"

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/vmalloc.h>
#include <linux/highmem.h>
#include <linux/sched.h>
#include <linux/ftrace_event.h>
#include <linux/slab.h>

#include <asm/tlbflush.h>
#include <asm/desc.h>
#include <asm/kvm_para.h>

#include <asm/virtext.h>
#include "trace.h"

#define __ex(x) __kvm_handle_fault_on_reboot(x)

MODULE_AUTHOR("Qumranet");
MODULE_LICENSE("GPL");

#define IOPM_ALLOC_ORDER 2
#define MSRPM_ALLOC_ORDER 1

#define SEG_TYPE_LDT 2
#define SEG_TYPE_BUSY_TSS16 3

#define SVM_FEATURE_NPT            (1 <<  0)
#define SVM_FEATURE_LBRV           (1 <<  1)
#define SVM_FEATURE_SVML           (1 <<  2)
#define SVM_FEATURE_NRIP           (1 <<  3)
#define SVM_FEATURE_TSC_RATE       (1 <<  4)
#define SVM_FEATURE_VMCB_CLEAN     (1 <<  5)
#define SVM_FEATURE_FLUSH_ASID     (1 <<  6)
#define SVM_FEATURE_DECODE_ASSIST  (1 <<  7)
#define SVM_FEATURE_PAUSE_FILTER   (1 << 10)

#define NESTED_EXIT_HOST	0	/* Exit handled on host level */
#define NESTED_EXIT_DONE	1	/* Exit caused nested vmexit  */
#define NESTED_EXIT_CONTINUE	2	/* Further checks needed      */

#define DEBUGCTL_RESERVED_BITS (~(0x3fULL))

#define TSC_RATIO_RSVD          0xffffff0000000000ULL
#define TSC_RATIO_MIN		0x0000000000000001ULL
#define TSC_RATIO_MAX		0x000000ffffffffffULL

static bool erratum_383_found __read_mostly;

static const u32 host_save_user_msrs[] = {
#ifdef CONFIG_X86_64
	MSR_STAR, MSR_LSTAR, MSR_CSTAR, MSR_SYSCALL_MASK, MSR_KERNEL_GS_BASE,
	MSR_FS_BASE,
#endif
	MSR_IA32_SYSENTER_CS, MSR_IA32_SYSENTER_ESP, MSR_IA32_SYSENTER_EIP,
};

#define NR_HOST_SAVE_USER_MSRS ARRAY_SIZE(host_save_user_msrs)

struct kvm_vcpu;

struct nested_state {
	struct vmcb *hsave;
	u64 hsave_msr;
	u64 vm_cr_msr;
	u64 vmcb;

	/* These are the merged vectors */
	u32 *msrpm;

	/* gpa pointers to the real vectors */
	u64 vmcb_msrpm;
	u64 vmcb_iopm;

	/* A VMEXIT is required but not yet emulated */
	bool exit_required;

	/* cache for intercepts of the guest */
	u32 intercept_cr;
	u32 intercept_dr;
	u32 intercept_exceptions;
	u64 intercept;

	/* Nested Paging related state */
	u64 nested_cr3;
};

#define MSRPM_OFFSETS	16
static u32 msrpm_offsets[MSRPM_OFFSETS] __read_mostly;

struct vcpu_svm {
	struct kvm_vcpu vcpu;
	struct vmcb *vmcb;
	unsigned long vmcb_pa;
	struct svm_cpu_data *svm_data;
	uint64_t asid_generation;
	uint64_t sysenter_esp;
	uint64_t sysenter_eip;

	u64 next_rip;

	u64 host_user_msrs[NR_HOST_SAVE_USER_MSRS];
	struct {
		u16 fs;
		u16 gs;
		u16 ldt;
		u64 gs_base;
	} host;

	u32 *msrpm;

	ulong nmi_iret_rip;

	struct nested_state nested;

	bool nmi_singlestep;

	unsigned int3_injected;
	unsigned long int3_rip;
	u32 apf_reason;

	u64  tsc_ratio;
};

static DEFINE_PER_CPU(u64, current_tsc_ratio);
#define TSC_RATIO_DEFAULT	0x0100000000ULL

#define MSR_INVALID			0xffffffffU

static struct svm_direct_access_msrs {
	u32 index;   /* Index of the MSR */
	bool always; /* True if intercept is always on */
} direct_access_msrs[] = {
	{ .index = MSR_STAR,				.always = true  },
	{ .index = MSR_IA32_SYSENTER_CS,		.always = true  },
#ifdef CONFIG_X86_64
	{ .index = MSR_GS_BASE,				.always = true  },
	{ .index = MSR_FS_BASE,				.always = true  },
	{ .index = MSR_KERNEL_GS_BASE,			.always = true  },
	{ .index = MSR_LSTAR,				.always = true  },
	{ .index = MSR_CSTAR,				.always = true  },
	{ .index = MSR_SYSCALL_MASK,			.always = true  },
#endif
	{ .index = MSR_IA32_LASTBRANCHFROMIP,		.always = false },
	{ .index = MSR_IA32_LASTBRANCHTOIP,		.always = false },
	{ .index = MSR_IA32_LASTINTFROMIP,		.always = false },
	{ .index = MSR_IA32_LASTINTTOIP,		.always = false },
	{ .index = MSR_INVALID,				.always = false },
};

/* enable NPT for AMD64 and X86 with PAE */
#if defined(CONFIG_X86_64) || defined(CONFIG_X86_PAE)
static bool npt_enabled = true;
#else
static bool npt_enabled;
#endif
static int npt = 1;

module_param(npt, int, S_IRUGO);

static int nested = 1;
module_param(nested, int, S_IRUGO);

static void svm_flush_tlb(struct kvm_vcpu *vcpu);
static void svm_complete_interrupts(struct vcpu_svm *svm);

static int nested_svm_exit_handled(struct vcpu_svm *svm);
static int nested_svm_intercept(struct vcpu_svm *svm);
static int nested_svm_vmexit(struct vcpu_svm *svm);
static int nested_svm_check_exception(struct vcpu_svm *svm, unsigned nr,
				      bool has_error_code, u32 error_code);
static u64 __scale_tsc(u64 ratio, u64 tsc);

enum {
	VMCB_INTERCEPTS, /* Intercept vectors, TSC offset,
			    pause filter count */
	VMCB_PERM_MAP,   /* IOPM Base and MSRPM Base */
	VMCB_ASID,	 /* ASID */
	VMCB_INTR,	 /* int_ctl, int_vector */
	VMCB_NPT,        /* npt_en, nCR3, gPAT */
	VMCB_CR,	 /* CR0, CR3, CR4, EFER */
	VMCB_DR,         /* DR6, DR7 */
	VMCB_DT,         /* GDT, IDT */
	VMCB_SEG,        /* CS, DS, SS, ES, CPL */
	VMCB_CR2,        /* CR2 only */
	VMCB_LBR,        /* DBGCTL, BR_FROM, BR_TO, LAST_EX_FROM, LAST_EX_TO */
	VMCB_DIRTY_MAX,
};

/* TPR and CR2 are always written before VMRUN */
#define VMCB_ALWAYS_DIRTY_MASK	((1U << VMCB_INTR) | (1U << VMCB_CR2))

static inline void mark_all_dirty(struct vmcb *vmcb)
{
	vmcb->control.clean = 0;
}

static inline void mark_all_clean(struct vmcb *vmcb)
{
	vmcb->control.clean = ((1 << VMCB_DIRTY_MAX) - 1)
			       & ~VMCB_ALWAYS_DIRTY_MASK;
}

static inline void mark_dirty(struct vmcb *vmcb, int bit)
{
	vmcb->control.clean &= ~(1 << bit);
}

static inline struct vcpu_svm *to_svm(struct kvm_vcpu *vcpu)
{
	return container_of(vcpu, struct vcpu_svm, vcpu);
}

static void recalc_intercepts(struct vcpu_svm *svm)
{
	struct vmcb_control_area *c, *h;
	struct nested_state *g;

	mark_dirty(svm->vmcb, VMCB_INTERCEPTS);

	if (!is_guest_mode(&svm->vcpu))
		return;

	c = &svm->vmcb->control;
	h = &svm->nested.hsave->control;
	g = &svm->nested;

	c->intercept_cr = h->intercept_cr | g->intercept_cr;
	c->intercept_dr = h->intercept_dr | g->intercept_dr;
	c->intercept_exceptions = h->intercept_exceptions | g->intercept_exceptions;
	c->intercept = h->intercept | g->intercept;
}

static inline struct vmcb *get_host_vmcb(struct vcpu_svm *svm)
{
	if (is_guest_mode(&svm->vcpu))
		return svm->nested.hsave;
	else
		return svm->vmcb;
}

static inline void set_cr_intercept(struct vcpu_svm *svm, int bit)
{
	struct vmcb *vmcb = get_host_vmcb(svm);

	vmcb->control.intercept_cr |= (1U << bit);

	recalc_intercepts(svm);
}

static inline void clr_cr_intercept(struct vcpu_svm *svm, int bit)
{
	struct vmcb *vmcb = get_host_vmcb(svm);

	vmcb->control.intercept_cr &= ~(1U << bit);

	recalc_intercepts(svm);
}

static inline bool is_cr_intercept(struct vcpu_svm *svm, int bit)
{
	struct vmcb *vmcb = get_host_vmcb(svm);

	return vmcb->control.intercept_cr & (1U << bit);
}

static inline void set_dr_intercept(struct vcpu_svm *svm, int bit)
{
	struct vmcb *vmcb = get_host_vmcb(svm);

	vmcb->control.intercept_dr |= (1U << bit);

	recalc_intercepts(svm);
}

static inline void clr_dr_intercept(struct vcpu_svm *svm, int bit)
{
	struct vmcb *vmcb = get_host_vmcb(svm);

	vmcb->control.intercept_dr &= ~(1U << bit);

	recalc_intercepts(svm);
}

static inline void set_exception_intercept(struct vcpu_svm *svm, int bit)
{
	struct vmcb *vmcb = get_host_vmcb(svm);

	vmcb->control.intercept_exceptions |= (1U << bit);

	recalc_intercepts(svm);
}

static inline void clr_exception_intercept(struct vcpu_svm *svm, int bit)
{
	struct vmcb *vmcb = get_host_vmcb(svm);

	vmcb->control.intercept_exceptions &= ~(1U << bit);

	recalc_intercepts(svm);
}

static inline void set_intercept(struct vcpu_svm *svm, int bit)
{
	struct vmcb *vmcb = get_host_vmcb(svm);

	vmcb->control.intercept |= (1ULL << bit);

	recalc_intercepts(svm);
}

static inline void clr_intercept(struct vcpu_svm *svm, int bit)
{
	struct vmcb *vmcb = get_host_vmcb(svm);

	vmcb->control.intercept &= ~(1ULL << bit);

	recalc_intercepts(svm);
}

static inline void enable_gif(struct vcpu_svm *svm)
{
	svm->vcpu.arch.hflags |= HF_GIF_MASK;
}

static inline void disable_gif(struct vcpu_svm *svm)
{
	svm->vcpu.arch.hflags &= ~HF_GIF_MASK;
}

static inline bool gif_set(struct vcpu_svm *svm)
{
	return !!(svm->vcpu.arch.hflags & HF_GIF_MASK);
}

static unsigned long iopm_base;

struct kvm_ldttss_desc {
	u16 limit0;
	u16 base0;
	unsigned base1:8, type:5, dpl:2, p:1;
	unsigned limit1:4, zero0:3, g:1, base2:8;
	u32 base3;
	u32 zero1;
} __attribute__((packed));

struct svm_cpu_data {
	int cpu;

	u64 asid_generation;
	u32 max_asid;
	u32 next_asid;
	struct kvm_ldttss_desc *tss_desc;

	struct page *save_area;
};

static DEFINE_PER_CPU(struct svm_cpu_data *, svm_data);

struct svm_init_data {
	int cpu;
	int r;
};

static u32 msrpm_ranges[] = {0, 0xc0000000, 0xc0010000};

#define NUM_MSR_MAPS ARRAY_SIZE(msrpm_ranges)
#define MSRS_RANGE_SIZE 2048
#define MSRS_IN_RANGE (MSRS_RANGE_SIZE * 8 / 2)

static u32 svm_msrpm_offset(u32 msr)
{
	u32 offset;
	int i;

	for (i = 0; i < NUM_MSR_MAPS; i++) {
		if (msr < msrpm_ranges[i] ||
		    msr >= msrpm_ranges[i] + MSRS_IN_RANGE)
			continue;

		offset  = (msr - msrpm_ranges[i]) / 4; /* 4 msrs per u8 */
		offset += (i * MSRS_RANGE_SIZE);       /* add range offset */

		/* Now we have the u8 offset - but need the u32 offset */
		return offset / 4;
	}

	/* MSR not in any range */
	return MSR_INVALID;
}

#define MAX_INST_SIZE 15

static inline void clgi(void)
{
	asm volatile (__ex(SVM_CLGI));
}

static inline void stgi(void)
{
	asm volatile (__ex(SVM_STGI));
}

static inline void invlpga(unsigned long addr, u32 asid)
{
	asm volatile (__ex(SVM_INVLPGA) : : "a"(addr), "c"(asid));
}

static int get_npt_level(void)
{
#ifdef CONFIG_X86_64
	return PT64_ROOT_LEVEL;
#else
	return PT32E_ROOT_LEVEL;
#endif
}

static void svm_set_efer(struct kvm_vcpu *vcpu, u64 efer)
{
	vcpu->arch.efer = efer;
	if (!npt_enabled && !(efer & EFER_LMA))
		efer &= ~EFER_LME;

	to_svm(vcpu)->vmcb->save.efer = efer | EFER_SVME;
	mark_dirty(to_svm(vcpu)->vmcb, VMCB_CR);
}

static int is_external_interrupt(u32 info)
{
	info &= SVM_EVTINJ_TYPE_MASK | SVM_EVTINJ_VALID;
	return info == (SVM_EVTINJ_VALID | SVM_EVTINJ_TYPE_INTR);
}

static u32 svm_get_interrupt_shadow(struct kvm_vcpu *vcpu, int mask)
{
	struct vcpu_svm *svm = to_svm(vcpu);
	u32 ret = 0;

	if (svm->vmcb->control.int_state & SVM_INTERRUPT_SHADOW_MASK)
		ret |= KVM_X86_SHADOW_INT_STI | KVM_X86_SHADOW_INT_MOV_SS;
	return ret & mask;
}

static void svm_set_interrupt_shadow(struct kvm_vcpu *vcpu, int mask)
{
	struct vcpu_svm *svm = to_svm(vcpu);

	if (mask == 0)
		svm->vmcb->control.int_state &= ~SVM_INTERRUPT_SHADOW_MASK;
	else
		svm->vmcb->control.int_state |= SVM_INTERRUPT_SHADOW_MASK;

}

static void skip_emulated_instruction(struct kvm_vcpu *vcpu)
{
	struct vcpu_svm *svm = to_svm(vcpu);

	if (svm->vmcb->control.next_rip != 0)
		svm->next_rip = svm->vmcb->control.next_rip;

	if (!svm->next_rip) {
		if (emulate_instruction(vcpu, EMULTYPE_SKIP) !=
				EMULATE_DONE)
			printk(KERN_DEBUG "%s: NOP\n", __func__);
		return;
	}
	if (svm->next_rip - kvm_rip_read(vcpu) > MAX_INST_SIZE)
		printk(KERN_ERR "%s: ip 0x%lx next 0x%llx\n",
		       __func__, kvm_rip_read(vcpu), svm->next_rip);

	kvm_rip_write(vcpu, svm->next_rip);
	svm_set_interrupt_shadow(vcpu, 0);
}

static void svm_queue_exception(struct kvm_vcpu *vcpu, unsigned nr,
				bool has_error_code, u32 error_code,
				bool reinject)
{
	struct vcpu_svm *svm = to_svm(vcpu);

	/*
	 * If we are within a nested VM we'd better #VMEXIT and let the guest
	 * handle the exception
	 */
	if (!reinject &&
	    nested_svm_check_exception(svm, nr, has_error_code, error_code))
		return;

	if (nr == BP_VECTOR && !static_cpu_has(X86_FEATURE_NRIPS)) {
		unsigned long rip, old_rip = kvm_rip_read(&svm->vcpu);

		/*
		 * For guest debugging where we have to reinject #BP if some
		 * INT3 is guest-owned:
		 * Emulate nRIP by moving RIP forward. Will fail if injection
		 * raises a fault that is not intercepted. Still better than
		 * failing in all cases.
		 */
		skip_emulated_instruction(&svm->vcpu);
		rip = kvm_rip_read(&svm->vcpu);
		svm->int3_rip = rip + svm->vmcb->save.cs.base;
		svm->int3_injected = rip - old_rip;
	}

	svm->vmcb->control.event_inj = nr
		| SVM_EVTINJ_VALID
		| (has_error_code ? SVM_EVTINJ_VALID_ERR : 0)
		| SVM_EVTINJ_TYPE_EXEPT;
	svm->vmcb->control.event_inj_err = error_code;
}

static void svm_init_erratum_383(void)
{
	u32 low, high;
	int err;
	u64 val;

	if (!cpu_has_amd_erratum(amd_erratum_383))
		return;

	/* Use _safe variants to not break nested virtualization */
	val = native_read_msr_safe(MSR_AMD64_DC_CFG, &err);
	if (err)
		return;

	val |= (1ULL << 47);

	low  = lower_32_bits(val);
	high = upper_32_bits(val);

	native_write_msr_safe(MSR_AMD64_DC_CFG, low, high);

	erratum_383_found = true;
}

static int has_svm(void)
{
	const char *msg;

	if (!cpu_has_svm(&msg)) {
		printk(KERN_INFO "has_svm: %s\n", msg);
		return 0;
	}

	return 1;
}

static void svm_hardware_disable(void *garbage)
{
	/* Make sure we clean up behind us */
	if (static_cpu_has(X86_FEATURE_TSCRATEMSR))
		wrmsrl(MSR_AMD64_TSC_RATIO, TSC_RATIO_DEFAULT);

	cpu_svm_disable();
}

static int svm_hardware_enable(void *garbage)
{

	struct svm_cpu_data *sd;
	uint64_t efer;
	struct desc_ptr gdt_descr;
	struct desc_struct *gdt;
	int me = raw_smp_processor_id();

	rdmsrl(MSR_EFER, efer);
	if (efer & EFER_SVME)
		return -EBUSY;

	if (!has_svm()) {
		printk(KERN_ERR "svm_hardware_enable: err EOPNOTSUPP on %d\n",
		       me);
		return -EINVAL;
	}
	sd = per_cpu(svm_data, me);

	if (!sd) {
		printk(KERN_ERR "svm_hardware_enable: svm_data is NULL on %d\n",
		       me);
		return -EINVAL;
	}

	sd->asid_generation = 1;
	sd->max_asid = cpuid_ebx(SVM_CPUID_FUNC) - 1;
	sd->next_asid = sd->max_asid + 1;

	native_store_gdt(&gdt_descr);
	gdt = (struct desc_struct *)gdt_descr.address;
	sd->tss_desc = (struct kvm_ldttss_desc *)(gdt + GDT_ENTRY_TSS);

	wrmsrl(MSR_EFER, efer | EFER_SVME);

	wrmsrl(MSR_VM_HSAVE_PA, page_to_pfn(sd->save_area) << PAGE_SHIFT);

	if (static_cpu_has(X86_FEATURE_TSCRATEMSR)) {
		wrmsrl(MSR_AMD64_TSC_RATIO, TSC_RATIO_DEFAULT);
		__get_cpu_var(current_tsc_ratio) = TSC_RATIO_DEFAULT;
	}

	svm_init_erratum_383();

	return 0;
}

static void svm_cpu_uninit(int cpu)
{
	struct svm_cpu_data *sd = per_cpu(svm_data, raw_smp_processor_id());

	if (!sd)
		return;

	per_cpu(svm_data, raw_smp_processor_id()) = NULL;
	__free_page(sd->save_area);
	kfree(sd);
}

static int svm_cpu_init(int cpu)
{
	struct svm_cpu_data *sd;
	int r;

	sd = kzalloc(sizeof(struct svm_cpu_data), GFP_KERNEL);
	if (!sd)
		return -ENOMEM;
	sd->cpu = cpu;
	sd->save_area = alloc_page(GFP_KERNEL);
	r = -ENOMEM;
	if (!sd->save_area)
		goto err_1;

	per_cpu(svm_data, cpu) = sd;

	return 0;

err_1:
	kfree(sd);
	return r;

}

static bool valid_msr_intercept(u32 index)
{
	int i;

	for (i = 0; direct_access_msrs[i].index != MSR_INVALID; i++)
		if (direct_access_msrs[i].index == index)
			return true;

	return false;
}

static void set_msr_interception(u32 *msrpm, unsigned msr,
				 int read, int write)
{
	u8 bit_read, bit_write;
	unsigned long tmp;
	u32 offset;

	/*
	 * If this warning triggers extend the direct_access_msrs list at the
	 * beginning of the file
	 */
	WARN_ON(!valid_msr_intercept(msr));

	offset    = svm_msrpm_offset(msr);
	bit_read  = 2 * (msr & 0x0f);
	bit_write = 2 * (msr & 0x0f) + 1;
	tmp       = msrpm[offset];

	BUG_ON(offset == MSR_INVALID);

	read  ? clear_bit(bit_read,  &tmp) : set_bit(bit_read,  &tmp);
	write ? clear_bit(bit_write, &tmp) : set_bit(bit_write, &tmp);

	msrpm[offset] = tmp;
}

static void svm_vcpu_init_msrpm(u32 *msrpm)
{
	int i;

	memset(msrpm, 0xff, PAGE_SIZE * (1 << MSRPM_ALLOC_ORDER));

	for (i = 0; direct_access_msrs[i].index != MSR_INVALID; i++) {
		if (!direct_access_msrs[i].always)
			continue;

		set_msr_interception(msrpm, direct_access_msrs[i].index, 1, 1);
	}
}

static void add_msr_offset(u32 offset)
{
	int i;

	for (i = 0; i < MSRPM_OFFSETS; ++i) {

		/* Offset already in list? */
		if (msrpm_offsets[i] == offset)
			return;

		/* Slot used by another offset? */
		if (msrpm_offsets[i] != MSR_INVALID)
			continue;

		/* Add offset to list */
		msrpm_offsets[i] = offset;

		return;
	}

	/*
	 * If this BUG triggers the msrpm_offsets table has an overflow. Just
	 * increase MSRPM_OFFSETS in this case.
	 */
	BUG();
}

static void init_msrpm_offsets(void)
{
	int i;

	memset(msrpm_offsets, 0xff, sizeof(msrpm_offsets));

	for (i = 0; direct_access_msrs[i].index != MSR_INVALID; i++) {
		u32 offset;

		offset = svm_msrpm_offset(direct_access_msrs[i].index);
		BUG_ON(offset == MSR_INVALID);

		add_msr_offset(offset);
	}
}

static void svm_enable_lbrv(struct vcpu_svm *svm)
{
	u32 *msrpm = svm->msrpm;

	svm->vmcb->control.lbr_ctl = 1;
	set_msr_interception(msrpm, MSR_IA32_LASTBRANCHFROMIP, 1, 1);
	set_msr_interception(msrpm, MSR_IA32_LASTBRANCHTOIP, 1, 1);
	set_msr_interception(msrpm, MSR_IA32_LASTINTFROMIP, 1, 1);
	set_msr_interception(msrpm, MSR_IA32_LASTINTTOIP, 1, 1);
}

static void svm_disable_lbrv(struct vcpu_svm *svm)
{
	u32 *msrpm = svm->msrpm;

	svm->vmcb->control.lbr_ctl = 0;
	set_msr_interception(msrpm, MSR_IA32_LASTBRANCHFROMIP, 0, 0);
	set_msr_interception(msrpm, MSR_IA32_LASTBRANCHTOIP, 0, 0);
	set_msr_interception(msrpm, MSR_IA32_LASTINTFROMIP, 0, 0);
	set_msr_interception(msrpm, MSR_IA32_LASTINTTOIP, 0, 0);
}

static __init int svm_hardware_setup(void)
{
	int cpu;
	struct page *iopm_pages;
	void *iopm_va;
	int r;

	iopm_pages = alloc_pages(GFP_KERNEL, IOPM_ALLOC_ORDER);

	if (!iopm_pages)
		return -ENOMEM;

	iopm_va = page_address(iopm_pages);
	memset(iopm_va, 0xff, PAGE_SIZE * (1 << IOPM_ALLOC_ORDER));
	iopm_base = page_to_pfn(iopm_pages) << PAGE_SHIFT;

	init_msrpm_offsets();

	if (boot_cpu_has(X86_FEATURE_NX))
		kvm_enable_efer_bits(EFER_NX);

	if (boot_cpu_has(X86_FEATURE_FXSR_OPT))
		kvm_enable_efer_bits(EFER_FFXSR);

	if (boot_cpu_has(X86_FEATURE_TSCRATEMSR)) {
		u64 max;

		kvm_has_tsc_control = true;

		/*
		 * Make sure the user can only configure tsc_khz values that
		 * fit into a signed integer.
		 * A min value is not calculated needed because it will always
		 * be 1 on all machines and a value of 0 is used to disable
		 * tsc-scaling for the vcpu.
		 */
		max = min(0x7fffffffULL, __scale_tsc(tsc_khz, TSC_RATIO_MAX));

		kvm_max_guest_tsc_khz = max;
	}

	if (nested) {
		printk(KERN_INFO "kvm: Nested Virtualization enabled\n");
		kvm_enable_efer_bits(EFER_SVME | EFER_LMSLE);
	}

	for_each_possible_cpu(cpu) {
		r = svm_cpu_init(cpu);
		if (r)
			goto err;
	}

	if (!boot_cpu_has(X86_FEATURE_NPT))
		npt_enabled = false;

	if (npt_enabled && !npt) {
		printk(KERN_INFO "kvm: Nested Paging disabled\n");
		npt_enabled = false;
	}

	if (npt_enabled) {
		printk(KERN_INFO "kvm: Nested Paging enabled\n");
		kvm_enable_tdp();
	} else
		kvm_disable_tdp();

	return 0;

err:
	__free_pages(iopm_pages, IOPM_ALLOC_ORDER);
	iopm_base = 0;
	return r;
}

static __exit void svm_hardware_unsetup(void)
{
	int cpu;

	for_each_possible_cpu(cpu)
		svm_cpu_uninit(cpu);

	__free_pages(pfn_to_page(iopm_base >> PAGE_SHIFT), IOPM_ALLOC_ORDER);
	iopm_base = 0;
}

static void init_seg(struct vmcb_seg *seg)
{
	seg->selector = 0;
	seg->attrib = SVM_SELECTOR_P_MASK | SVM_SELECTOR_S_MASK |
		      SVM_SELECTOR_WRITE_MASK; /* Read/Write Data Segment */
	seg->limit = 0xffff;
	seg->base = 0;
}

static void init_sys_seg(struct vmcb_seg *seg, uint32_t type)
{
	seg->selector = 0;
	seg->attrib = SVM_SELECTOR_P_MASK | type;
	seg->limit = 0xffff;
	seg->base = 0;
}

static u64 __scale_tsc(u64 ratio, u64 tsc)
{
	u64 mult, frac, _tsc;

	mult  = ratio >> 32;
	frac  = ratio & ((1ULL << 32) - 1);

	_tsc  = tsc;
	_tsc *= mult;
	_tsc += (tsc >> 32) * frac;
	_tsc += ((tsc & ((1ULL << 32) - 1)) * frac) >> 32;

	return _tsc;
}

static u64 svm_scale_tsc(struct kvm_vcpu *vcpu, u64 tsc)
{
	struct vcpu_svm *svm = to_svm(vcpu);
	u64 _tsc = tsc;

	if (svm->tsc_ratio != TSC_RATIO_DEFAULT)
		_tsc = __scale_tsc(svm->tsc_ratio, tsc);

	return _tsc;
}

static void svm_set_tsc_khz(struct kvm_vcpu *vcpu, u32 user_tsc_khz)
{
	struct vcpu_svm *svm = to_svm(vcpu);
	u64 ratio;
	u64 khz;

	/* TSC scaling supported? */
	if (!boot_cpu_has(X86_FEATURE_TSCRATEMSR))
		return;

	/* TSC-Scaling disabled or guest TSC same frequency as host TSC? */
	if (user_tsc_khz == 0) {
		vcpu->arch.virtual_tsc_khz = 0;
		svm->tsc_ratio = TSC_RATIO_DEFAULT;
		return;
	}

	khz = user_tsc_khz;

	/* TSC scaling required  - calculate ratio */
	ratio = khz << 32;
	do_div(ratio, tsc_khz);

	if (ratio == 0 || ratio & TSC_RATIO_RSVD) {
		WARN_ONCE(1, "Invalid TSC ratio - virtual-tsc-khz=%u\n",
				user_tsc_khz);
		return;
	}
	vcpu->arch.virtual_tsc_khz = user_tsc_khz;
	svm->tsc_ratio             = ratio;
}

static void svm_write_tsc_offset(struct kvm_vcpu *vcpu, u64 offset)
{
	struct vcpu_svm *svm = to_svm(vcpu);
	u64 g_tsc_offset = 0;

	if (is_guest_mode(vcpu)) {
		g_tsc_offset = svm->vmcb->control.tsc_offset -
			       svm->nested.hsave->control.tsc_offset;
		svm->nested.hsave->control.tsc_offset = offset;
	}

	svm->vmcb->control.tsc_offset = offset + g_tsc_offset;

	mark_dirty(svm->vmcb, VMCB_INTERCEPTS);
}

static void svm_adjust_tsc_offset(struct kvm_vcpu *vcpu, s64 adjustment)
{
	struct vcpu_svm *svm = to_svm(vcpu);

	svm->vmcb->control.tsc_offset += adjustment;
	if (is_guest_mode(vcpu))
		svm->nested.hsave->control.tsc_offset += adjustment;
	mark_dirty(svm->vmcb, VMCB_INTERCEPTS);
}

static u64 svm_compute_tsc_offset(struct kvm_vcpu *vcpu, u64 target_tsc)
{
	u64 tsc;

	tsc = svm_scale_tsc(vcpu, native_read_tsc());

	return target_tsc - tsc;
}

static void init_vmcb(struct vcpu_svm *svm)
{
	struct vmcb_control_area *control = &svm->vmcb->control;
	struct vmcb_save_area *save = &svm->vmcb->save;

	svm->vcpu.fpu_active = 1;
	svm->vcpu.arch.hflags = 0;

	set_cr_intercept(svm, INTERCEPT_CR0_READ);
	set_cr_intercept(svm, INTERCEPT_CR3_READ);
	set_cr_intercept(svm, INTERCEPT_CR4_READ);
	set_cr_intercept(svm, INTERCEPT_CR0_WRITE);
	set_cr_intercept(svm, INTERCEPT_CR3_WRITE);
	set_cr_intercept(svm, INTERCEPT_CR4_WRITE);
	set_cr_intercept(svm, INTERCEPT_CR8_WRITE);

	set_dr_intercept(svm, INTERCEPT_DR0_READ);
	set_dr_intercept(svm, INTERCEPT_DR1_READ);
	set_dr_intercept(svm, INTERCEPT_DR2_READ);
	set_dr_intercept(svm, INTERCEPT_DR3_READ);
	set_dr_intercept(svm, INTERCEPT_DR4_READ);
	set_dr_intercept(svm, INTERCEPT_DR5_READ);
	set_dr_intercept(svm, INTERCEPT_DR6_READ);
	set_dr_intercept(svm, INTERCEPT_DR7_READ);

	set_dr_intercept(svm, INTERCEPT_DR0_WRITE);
	set_dr_intercept(svm, INTERCEPT_DR1_WRITE);
	set_dr_intercept(svm, INTERCEPT_DR2_WRITE);
	set_dr_intercept(svm, INTERCEPT_DR3_WRITE);
	set_dr_intercept(svm, INTERCEPT_DR4_WRITE);
	set_dr_intercept(svm, INTERCEPT_DR5_WRITE);
	set_dr_intercept(svm, INTERCEPT_DR6_WRITE);
	set_dr_intercept(svm, INTERCEPT_DR7_WRITE);

	set_exception_intercept(svm, PF_VECTOR);
	set_exception_intercept(svm, UD_VECTOR);
	set_exception_intercept(svm, MC_VECTOR);

	set_intercept(svm, INTERCEPT_INTR);
	set_intercept(svm, INTERCEPT_NMI);
	set_intercept(svm, INTERCEPT_SMI);
	set_intercept(svm, INTERCEPT_SELECTIVE_CR0);
	set_intercept(svm, INTERCEPT_CPUID);
	set_intercept(svm, INTERCEPT_INVD);
	set_intercept(svm, INTERCEPT_HLT);
	set_intercept(svm, INTERCEPT_INVLPG);
	set_intercept(svm, INTERCEPT_INVLPGA);
	set_intercept(svm, INTERCEPT_IOIO_PROT);
	set_intercept(svm, INTERCEPT_MSR_PROT);
	set_intercept(svm, INTERCEPT_TASK_SWITCH);
	set_intercept(svm, INTERCEPT_SHUTDOWN);
	set_intercept(svm, INTERCEPT_VMRUN);
	set_intercept(svm, INTERCEPT_VMMCALL);
	set_intercept(svm, INTERCEPT_VMLOAD);
	set_intercept(svm, INTERCEPT_VMSAVE);
	set_intercept(svm, INTERCEPT_STGI);
	set_intercept(svm, INTERCEPT_CLGI);
	set_intercept(svm, INTERCEPT_SKINIT);
	set_intercept(svm, INTERCEPT_WBINVD);
	set_intercept(svm, INTERCEPT_MONITOR);
	set_intercept(svm, INTERCEPT_MWAIT);
	set_intercept(svm, INTERCEPT_XSETBV);

	control->iopm_base_pa = iopm_base;
	control->msrpm_base_pa = __pa(svm->msrpm);
	control->int_ctl = V_INTR_MASKING_MASK;

	init_seg(&save->es);
	init_seg(&save->ss);
	init_seg(&save->ds);
	init_seg(&save->fs);
	init_seg(&save->gs);

	save->cs.selector = 0xf000;
	/* Executable/Readable Code Segment */
	save->cs.attrib = SVM_SELECTOR_READ_MASK | SVM_SELECTOR_P_MASK |
		SVM_SELECTOR_S_MASK | SVM_SELECTOR_CODE_MASK;
	save->cs.limit = 0xffff;
	/*
	 * cs.base should really be 0xffff0000, but vmx can't handle that, so
	 * be consistent with it.
	 *
	 * Replace when we have real mode working for vmx.
	 */
	save->cs.base = 0xf0000;

	save->gdtr.limit = 0xffff;
	save->idtr.limit = 0xffff;

	init_sys_seg(&save->ldtr, SEG_TYPE_LDT);
	init_sys_seg(&save->tr, SEG_TYPE_BUSY_TSS16);

	svm_set_efer(&svm->vcpu, 0);
	save->dr6 = 0xffff0ff0;
	save->dr7 = 0x400;
	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.
	 */
	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;
	/* rdx = ?? */

	if (npt_enabled) {
		/* Setup VMCB for Nested Paging */
		control->nested_ctl = 1;
		clr_intercept(svm, INTERCEPT_INVLPG);
		clr_exception_intercept(svm, PF_VECTOR);
		clr_cr_intercept(svm, INTERCEPT_CR3_READ);
		clr_cr_intercept(svm, INTERCEPT_CR3_WRITE);
		save->g_pat = 0x0007040600070406ULL;
		save->cr3 = 0;
		save->cr4 = 0;
	}
	svm->asid_generation = 0;

	svm->nested.vmcb = 0;
	svm->vcpu.arch.hflags = 0;

	if (boot_cpu_has(X86_FEATURE_PAUSEFILTER)) {
		control->pause_filter_count = 3000;
		set_intercept(svm, INTERCEPT_PAUSE);
	}

	mark_all_dirty(svm->vmcb);

	enable_gif(svm);
}

static int svm_vcpu_reset(struct kvm_vcpu *vcpu)
{
	struct vcpu_svm *svm = to_svm(vcpu);

	init_vmcb(svm);

	if (!kvm_vcpu_is_bsp(vcpu)) {
		kvm_rip_write(vcpu, 0);
		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;

	return 0;
}

static struct kvm_vcpu *svm_create_vcpu(struct kvm *kvm, unsigned int id)
{
	struct vcpu_svm *svm;
	struct page *page;
	struct page *msrpm_pages;
	struct page *hsave_page;
	struct page *nested_msrpm_pages;
	int err;

	svm = kmem_cache_zalloc(kvm_vcpu_cache, GFP_KERNEL);
	if (!svm) {
		err = -ENOMEM;
		goto out;
	}

	svm->tsc_ratio = TSC_RATIO_DEFAULT;

	err = kvm_vcpu_init(&svm->vcpu, kvm, id);
	if (err)
		goto free_svm;

	err = -ENOMEM;
	page = alloc_page(GFP_KERNEL);
	if (!page)
		goto uninit;

	msrpm_pages = alloc_pages(GFP_KERNEL, MSRPM_ALLOC_ORDER);
	if (!msrpm_pages)
		goto free_page1;

	nested_msrpm_pages = alloc_pages(GFP_KERNEL, MSRPM_ALLOC_ORDER);
	if (!nested_msrpm_pages)
		goto free_page2;

	hsave_page = alloc_page(GFP_KERNEL);
	if (!hsave_page)
		goto free_page3;

	svm->nested.hsave = page_address(hsave_page);

	svm->msrpm = page_address(msrpm_pages);
	svm_vcpu_init_msrpm(svm->msrpm);

	svm->nested.msrpm = page_address(nested_msrpm_pages);
	svm_vcpu_init_msrpm(svm->nested.msrpm);

	svm->vmcb = page_address(page);
	clear_page(svm->vmcb);
	svm->vmcb_pa = page_to_pfn(page) << PAGE_SHIFT;
	svm->asid_generation = 0;
	init_vmcb(svm);
	kvm_write_tsc(&svm->vcpu, 0);

	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;

	return &svm->vcpu;

free_page4:
	__free_page(hsave_page);
free_page3:
	__free_pages(nested_msrpm_pages, MSRPM_ALLOC_ORDER);
free_page2:
	__free_pages(msrpm_pages, MSRPM_ALLOC_ORDER);
free_page1:
	__free_page(page);
uninit:
	kvm_vcpu_uninit(&svm->vcpu);
free_svm:
	kmem_cache_free(kvm_vcpu_cache, svm);
out:
	return ERR_PTR(err);
}

static void svm_free_vcpu(struct kvm_vcpu *vcpu)
{
	struct vcpu_svm *svm = to_svm(vcpu);

	__free_page(pfn_to_page(svm->vmcb_pa >> PAGE_SHIFT));
	__free_pages(virt_to_page(svm->msrpm), MSRPM_ALLOC_ORDER);
	__free_page(virt_to_page(svm->nested.hsave));
	__free_pages(virt_to_page(svm->nested.msrpm), MSRPM_ALLOC_ORDER);
	kvm_vcpu_uninit(vcpu);
	kmem_cache_free(kvm_vcpu_cache, svm);
}

static void svm_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
{
	struct vcpu_svm *svm = to_svm(vcpu);
	int i;

	if (unlikely(cpu != vcpu->cpu)) {
		svm->asid_generation = 0;
		mark_all_dirty(svm->vmcb);
	}

#ifdef CONFIG_X86_64
	rdmsrl(MSR_GS_BASE, to_svm(vcpu)->host.gs_base);
#endif
	savesegment(fs, svm->host.fs);
	savesegment(gs, svm->host.gs);
	svm->host.ldt = kvm_read_ldt();

	for (i = 0; i < NR_HOST_SAVE_USER_MSRS; i++)
		rdmsrl(host_save_user_msrs[i], svm->host_user_msrs[i]);

	if (static_cpu_has(X86_FEATURE_TSCRATEMSR) &&
	    svm->tsc_ratio != __get_cpu_var(current_tsc_ratio)) {
		__get_cpu_var(current_tsc_ratio) = svm->tsc_ratio;
		wrmsrl(MSR_AMD64_TSC_RATIO, svm->tsc_ratio);
	}
}

static void svm_vcpu_put(struct kvm_vcpu *vcpu)
{
	struct vcpu_svm *svm = to_svm(vcpu);
	int i;

	++vcpu->stat.host_state_reload;
	kvm_load_ldt(svm->host.ldt);
#ifdef CONFIG_X86_64
	loadsegment(fs, svm->host.fs);
	wrmsrl(MSR_KERNEL_GS_BASE, current->thread.gs);
	load_gs_index(svm->host.gs);
#else
#ifdef CONFIG_X86_32_LAZY_GS
	loadsegment(gs, svm->host.gs);
#endif
#endif
	for (i = 0; i < NR_HOST_SAVE_USER_MSRS; i++)
		wrmsrl(host_save_user_msrs[i], svm->host_user_msrs[i]);
}

static unsigned long svm_get_rflags(struct kvm_vcpu *vcpu)
{
	return to_svm(vcpu)->vmcb->save.rflags;
}

static void svm_set_rflags(struct kvm_vcpu *vcpu, unsigned long rflags)
{
	to_svm(vcpu)->vmcb->save.rflags = rflags;
}

static void svm_cache_reg(struct kvm_vcpu *vcpu, enum kvm_reg reg)
{
	switch (reg) {
	case VCPU_EXREG_PDPTR:
		BUG_ON(!npt_enabled);
		load_pdptrs(vcpu, vcpu->arch.walk_mmu, kvm_read_cr3(vcpu));
		break;
	default:
		BUG();
	}
}

static void svm_set_vintr(struct vcpu_svm *svm)
{
	set_intercept(svm, INTERCEPT_VINTR);
}

static void svm_clear_vintr(struct vcpu_svm *svm)
{
	clr_intercept(svm, INTERCEPT_VINTR);
}

static struct vmcb_seg *svm_seg(struct kvm_vcpu *vcpu, int seg)
{
	struct vmcb_save_area *save = &to_svm(vcpu)->vmcb->save;

	switch (seg) {
	case VCPU_SREG_CS: return &save->cs;
	case VCPU_SREG_DS: return &save->ds;
	case VCPU_SREG_ES: return &save->es;
	case VCPU_SREG_FS: return &save->fs;
	case VCPU_SREG_GS: return &save->gs;
	case VCPU_SREG_SS: return &save->ss;
	case VCPU_SREG_TR: return &save->tr;
	case VCPU_SREG_LDTR: return &save->ldtr;
	}
	BUG();
	return NULL;
}

static u64 svm_get_segment_base(struct kvm_vcpu *vcpu, int seg)
{
	struct vmcb_seg *s = svm_seg(vcpu, seg);

	return s->base;
}

static void svm_get_segment(struct kvm_vcpu *vcpu,
			    struct kvm_segment *var, int seg)
{
	struct vmcb_seg *s = svm_seg(vcpu, seg);

	var->base = s->base;
	var->limit = s->limit;
	var->selector = s->selector;
	var->type = s->attrib & SVM_SELECTOR_TYPE_MASK;
	var->s = (s->attrib >> SVM_SELECTOR_S_SHIFT) & 1;
	var->dpl = (s->attrib >> SVM_SELECTOR_DPL_SHIFT) & 3;
	var->present = (s->attrib >> SVM_SELECTOR_P_SHIFT) & 1;
	var->avl = (s->attrib >> SVM_SELECTOR_AVL_SHIFT) & 1;
	var->l = (s->attrib >> SVM_SELECTOR_L_SHIFT) & 1;
	var->db = (s->attrib >> SVM_SELECTOR_DB_SHIFT) & 1;
	var->g = (s->attrib >> SVM_SELECTOR_G_SHIFT) & 1;

	/*
	 * AMD's VMCB does not have an explicit unusable field, so emulate it
	 * for cross vendor migration purposes by "not present"
	 */
	var->unusable = !var->present || (var->type == 0);

	switch (seg) {
	case VCPU_SREG_CS:
		/*
		 * SVM always stores 0 for the 'G' bit in the CS selector in
		 * the VMCB on a VMEXIT. This hurts cross-vendor migration:
		 * Intel's VMENTRY has a check on the 'G' bit.
		 */
		var->g = s->limit > 0xfffff;
		break;
	case VCPU_SREG_TR:
		/*
		 * Work around a bug where the busy flag in the tr selector
		 * isn't exposed
		 */
		var->type |= 0x2;
		break;
	case VCPU_SREG_DS:
	case VCPU_SREG_ES:
	case VCPU_SREG_FS:
	case VCPU_SREG_GS:
		/*
		 * The accessed bit must always be set in the segment
		 * descriptor cache, although it can be cleared in the
		 * descriptor, the cached bit always remains at 1. Since
		 * Intel has a check on this, set it here to support
		 * cross-vendor migration.
		 */
		if (!var->unusable)
			var->type |= 0x1;
		break;
	case VCPU_SREG_SS:
		/*
		 * On AMD CPUs sometimes the DB bit in the segment
		 * descriptor is left as 1, although the whole segment has
		 * been made unusable. Clear it here to pass an Intel VMX
		 * entry check when cross vendor migrating.
		 */
		if (var->unusable)
			var->db = 0;
		break;
	}
}

static int svm_get_cpl(struct kvm_vcpu *vcpu)
{
	struct vmcb_save_area *save = &to_svm(vcpu)->vmcb->save;

	return save->cpl;
}

static void svm_get_idt(struct kvm_vcpu *vcpu, struct desc_ptr *dt)
{
	struct vcpu_svm *svm = to_svm(vcpu);

	dt->size = svm->vmcb->save.idtr.limit;
	dt->address = svm->vmcb->save.idtr.base;
}

static void svm_set_idt(struct kvm_vcpu *vcpu, struct desc_ptr *dt)
{
	struct vcpu_svm *svm = to_svm(vcpu);

	svm->vmcb->save.idtr.limit = dt->size;
	svm->vmcb->save.idtr.base = dt->address ;
	mark_dirty(svm->vmcb, VMCB_DT);
}

static void svm_get_gdt(struct kvm_vcpu *vcpu, struct desc_ptr *dt)
{
	struct vcpu_svm *svm = to_svm(vcpu);

	dt->size = svm->vmcb->save.gdtr.limit;
	dt->address = svm->vmcb->save.gdtr.base;
}

static void svm_set_gdt(struct kvm_vcpu *vcpu, struct desc_ptr *dt)
{
	struct vcpu_svm *svm = to_svm(vcpu);

	svm->vmcb->save.gdtr.limit = dt->size;
	svm->vmcb->save.gdtr.base = dt->address ;
	mark_dirty(svm->vmcb, VMCB_DT);
}

static void svm_decache_cr0_guest_bits(struct kvm_vcpu *vcpu)
{
}

static void svm_decache_cr3(struct kvm_vcpu *vcpu)
{
}

static void svm_decache_cr4_guest_bits(struct kvm_vcpu *vcpu)
{
}

static void update_cr0_intercept(struct vcpu_svm *svm)
{
	ulong gcr0 = svm->vcpu.arch.cr0;
	u64 *hcr0 = &svm->vmcb->save.cr0;

	if (!svm->vcpu.fpu_active)
		*hcr0 |= SVM_CR0_SELECTIVE_MASK;
	else
		*hcr0 = (*hcr0 & ~SVM_CR0_SELECTIVE_MASK)
			| (gcr0 & SVM_CR0_SELECTIVE_MASK);

	mark_dirty(svm->vmcb, VMCB_CR);

	if (gcr0 == *hcr0 && svm->vcpu.fpu_active) {
		clr_cr_intercept(svm, INTERCEPT_CR0_READ);
		clr_cr_intercept(svm, INTERCEPT_CR0_WRITE);
	} else {
		set_cr_intercept(svm, INTERCEPT_CR0_READ);
		set_cr_intercept(svm, INTERCEPT_CR0_WRITE);
	}
}

static void svm_set_cr0(struct kvm_vcpu *vcpu, unsigned long cr0)
{
	struct vcpu_svm *svm = to_svm(vcpu);

#ifdef CONFIG_X86_64
	if (vcpu->arch.efer & EFER_LME) {
		if (!is_paging(vcpu) && (cr0 & X86_CR0_PG)) {
			vcpu->arch.efer |= EFER_LMA;
			svm->vmcb->save.efer |= EFER_LMA | EFER_LME;
		}

		if (is_paging(vcpu) && !(cr0 & X86_CR0_PG)) {
			vcpu->arch.efer &= ~EFER_LMA;
			svm->vmcb->save.efer &= ~(EFER_LMA | EFER_LME);
		}
	}
#endif
	vcpu->arch.cr0 = cr0;

	if (!npt_enabled)
		cr0 |= X86_CR0_PG | X86_CR0_WP;

	if (!vcpu->fpu_active)
		cr0 |= X86_CR0_TS;
	/*
	 * re-enable caching here because the QEMU bios
	 * does not do it - this results in some delay at
	 * reboot
	 */
	cr0 &= ~(X86_CR0_CD | X86_CR0_NW);
	svm->vmcb->save.cr0 = cr0;
	mark_dirty(svm->vmcb, VMCB_CR);
	update_cr0_intercept(svm);
}

static int svm_set_cr4(struct kvm_vcpu *vcpu, unsigned long cr4)
{
	unsigned long host_cr4_mce = read_cr4() & X86_CR4_MCE;
	unsigned long old_cr4 = to_svm(vcpu)->vmcb->save.cr4;

	if (cr4 & X86_CR4_VMXE)
		return 1;

	if (npt_enabled && ((old_cr4 ^ cr4) & X86_CR4_PGE))
		svm_flush_tlb(vcpu);

	vcpu->arch.cr4 = cr4;
	if (!npt_enabled)
		cr4 |= X86_CR4_PAE;
	cr4 |= host_cr4_mce;
	to_svm(vcpu)->vmcb->save.cr4 = cr4;
	mark_dirty(to_svm(vcpu)->vmcb, VMCB_CR);
	return 0;
}

static void svm_set_segment(struct kvm_vcpu *vcpu,
			    struct kvm_segment *var, int seg)
{
	struct vcpu_svm *svm = to_svm(vcpu);
	struct vmcb_seg *s = svm_seg(vcpu, seg);

	s->base = var->base;
	s->limit = var->limit;
	s->selector = var->selector;
	if (var->unusable)
		s->attrib = 0;
	else {
		s->attrib = (var->type & SVM_SELECTOR_TYPE_MASK);
		s->attrib |= (var->s & 1) << SVM_SELECTOR_S_SHIFT;
		s->attrib |= (var->dpl & 3) << SVM_SELECTOR_DPL_SHIFT;
		s->attrib |= (var->present & 1) << SVM_SELECTOR_P_SHIFT;
		s->attrib |= (var->avl & 1) << SVM_SELECTOR_AVL_SHIFT;
		s->attrib |= (var->l & 1) << SVM_SELECTOR_L_SHIFT;
		s->attrib |= (var->db & 1) << SVM_SELECTOR_DB_SHIFT;
		s->attrib |= (var->g & 1) << SVM_SELECTOR_G_SHIFT;
	}
	if (seg == VCPU_SREG_CS)
		svm->vmcb->save.cpl
			= (svm->vmcb->save.cs.attrib
			   >> SVM_SELECTOR_DPL_SHIFT) & 3;

	mark_dirty(svm->vmcb, VMCB_SEG);
}

static void update_db_intercept(struct kvm_vcpu *vcpu)
{
	struct vcpu_svm *svm = to_svm(vcpu);

	clr_exception_intercept(svm, DB_VECTOR);
	clr_exception_intercept(svm, BP_VECTOR);

	if (svm->nmi_singlestep)
		set_exception_intercept(svm, DB_VECTOR);

	if (vcpu->guest_debug & KVM_GUESTDBG_ENABLE) {
		if (vcpu->guest_debug &
		    (KVM_GUESTDBG_SINGLESTEP | KVM_GUESTDBG_USE_HW_BP))
			set_exception_intercept(svm, DB_VECTOR);
		if (vcpu->guest_debug & KVM_GUESTDBG_USE_SW_BP)
			set_exception_intercept(svm, BP_VECTOR);
	} else
		vcpu->guest_debug = 0;
}

static void svm_guest_debug(struct kvm_vcpu *vcpu, struct kvm_guest_debug *dbg)
{
	struct vcpu_svm *svm = to_svm(vcpu);

	if (vcpu->guest_debug & KVM_GUESTDBG_USE_HW_BP)
		svm->vmcb->save.dr7 = dbg->arch.debugreg[7];
	else
		svm->vmcb->save.dr7 = vcpu->arch.dr7;

	mark_dirty(svm->vmcb, VMCB_DR);

	update_db_intercept(vcpu);
}

static void new_asid(struct vcpu_svm *svm, struct svm_cpu_data *sd)
{
	if (sd->next_asid > sd->max_asid) {
		++sd->asid_generation;
		sd->next_asid = 1;
		svm->vmcb->control.tlb_ctl = TLB_CONTROL_FLUSH_ALL_ASID;
	}

	svm->asid_generation = sd->asid_generation;
	svm->vmcb->control.asid = sd->next_asid++;

	mark_dirty(svm->vmcb, VMCB_ASID);
}

static void svm_set_dr7(struct kvm_vcpu *vcpu, unsigned long value)
{
	struct vcpu_svm *svm = to_svm(vcpu);

	svm->vmcb->save.dr7 = value;
	mark_dirty(svm->vmcb, VMCB_DR);
}

static int pf_interception(struct vcpu_svm *svm)
{
	u64 fault_address = svm->vmcb->control.exit_info_2;
	u32 error_code;
	int r = 1;

	switch (svm->apf_reason) {
	default:
		error_code = svm->vmcb->control.exit_info_1;

		trace_kvm_page_fault(fault_address, error_code);
		if (!npt_enabled && kvm_event_needs_reinjection(&svm->vcpu))
			kvm_mmu_unprotect_page_virt(&svm->vcpu, fault_address);
		r = kvm_mmu_page_fault(&svm->vcpu, fault_address, error_code,
			svm->vmcb->control.insn_bytes,
			svm->vmcb->control.insn_len);
		break;
	case KVM_PV_REASON_PAGE_NOT_PRESENT:
		svm->apf_reason = 0;
		local_irq_disable();
		kvm_async_pf_task_wait(fault_address);
		local_irq_enable();
		break;
	case KVM_PV_REASON_PAGE_READY:
		svm->apf_reason = 0;
		local_irq_disable();
		kvm_async_pf_task_wake(fault_address);
		local_irq_enable();
		break;
	}
	return r;
}

static int db_interception(struct vcpu_svm *svm)
{
	struct kvm_run *kvm_run = svm->vcpu.run;

	if (!(svm->vcpu.guest_debug &
	      (KVM_GUESTDBG_SINGLESTEP | KVM_GUESTDBG_USE_HW_BP)) &&
		!svm->nmi_singlestep) {
		kvm_queue_exception(&svm->vcpu, DB_VECTOR);
		return 1;
	}

	if (svm->nmi_singlestep) {
		svm->nmi_singlestep = false;
		if (!(svm->vcpu.guest_debug & KVM_GUESTDBG_SINGLESTEP))
			svm->vmcb->save.rflags &=
				~(X86_EFLAGS_TF | X86_EFLAGS_RF);
		update_db_intercept(&svm->vcpu);
	}

	if (svm->vcpu.guest_debug &
	    (KVM_GUESTDBG_SINGLESTEP | KVM_GUESTDBG_USE_HW_BP)) {
		kvm_run->exit_reason = KVM_EXIT_DEBUG;
		kvm_run->debug.arch.pc =
			svm->vmcb->save.cs.base + svm->vmcb->save.rip;
		kvm_run->debug.arch.exception = DB_VECTOR;
		return 0;
	}

	return 1;
}

static int bp_interception(struct vcpu_svm *svm)
{
	struct kvm_run *kvm_run = svm->vcpu.run;

	kvm_run->exit_reason = KVM_EXIT_DEBUG;
	kvm_run->debug.arch.pc = svm->vmcb->save.cs.base + svm->vmcb->save.rip;
	kvm_run->debug.arch.exception = BP_VECTOR;
	return 0;
}

static int ud_interception(struct vcpu_svm *svm)
{
	int er;

	er = emulate_instruction(&svm->vcpu, EMULTYPE_TRAP_UD);
	if (er != EMULATE_DONE)
		kvm_queue_exception(&svm->vcpu, UD_VECTOR);
	return 1;
}

static void svm_fpu_activate(struct kvm_vcpu *vcpu)
{
	struct vcpu_svm *svm = to_svm(vcpu);

	clr_exception_intercept(svm, NM_VECTOR);

	svm->vcpu.fpu_active = 1;
	update_cr0_intercept(svm);
}

static int nm_interception(struct vcpu_svm *svm)
{
	svm_fpu_activate(&svm->vcpu);
	return 1;
}

static bool is_erratum_383(void)
{
	int err, i;
	u64 value;

	if (!erratum_383_found)
		return false;

	value = native_read_msr_safe(MSR_IA32_MC0_STATUS, &err);
	if (err)
		return false;

	/* Bit 62 may or may not be set for this mce */
	value &= ~(1ULL << 62);

	if (value != 0xb600000000010015ULL)
		return false;

	/* Clear MCi_STATUS registers */
	for (i = 0; i < 6; ++i)
		native_write_msr_safe(MSR_IA32_MCx_STATUS(i), 0, 0);

	value = native_read_msr_safe(MSR_IA32_MCG_STATUS, &err);
	if (!err) {
		u32 low, high;

		value &= ~(1ULL << 2);
		low    = lower_32_bits(value);
		high   = upper_32_bits(value);

		native_write_msr_safe(MSR_IA32_MCG_STATUS, low, high);
	}

	/* Flush tlb to evict multi-match entries */
	__flush_tlb_all();

	return true;
}

static void svm_handle_mce(struct vcpu_svm *svm)
{
	if (is_erratum_383()) {
		/*
		 * Erratum 383 triggered. Guest state is corrupt so kill the
		 * guest.
		 */
		pr_err("KVM: Guest triggered AMD Erratum 383\n");

		kvm_make_request(KVM_REQ_TRIPLE_FAULT, &svm->vcpu);

		return;
	}

	/*
	 * On an #MC intercept the MCE handler is not called automatically in
	 * the host. So do it by hand here.
	 */
	asm volatile (
		"int $0x12\n");
	/* not sure if we ever come back to this point */

	return;
}

static int mc_interception(struct vcpu_svm *svm)
{
	return 1;
}

static int shutdown_interception(struct vcpu_svm *svm)
{
	struct kvm_run *kvm_run = svm->vcpu.run;

	/*
	 * VMCB is undefined after a SHUTDOWN intercept
	 * so reinitialize it.
	 */
	clear_page(svm->vmcb);
	init_vmcb(svm);

	kvm_run->exit_reason = KVM_EXIT_SHUTDOWN;
	return 0;
}

static int io_interception(struct vcpu_svm *svm)
{
	struct kvm_vcpu *vcpu = &svm->vcpu;
	u32 io_info = svm->vmcb->control.exit_info_1; /* address size bug? */
	int size, in, string;
	unsigned port;

	++svm->vcpu.stat.io_exits;
	string = (io_info & SVM_IOIO_STR_MASK) != 0;
	in = (io_info & SVM_IOIO_TYPE_MASK) != 0;
	if (string || in)
		return emulate_instruction(vcpu, 0) == EMULATE_DONE;

	port = io_info >> 16;
	size = (io_info & SVM_IOIO_SIZE_MASK) >> SVM_IOIO_SIZE_SHIFT;
	svm->next_rip = svm->vmcb->control.exit_info_2;
	skip_emulated_instruction(&svm->vcpu);

	return kvm_fast_pio_out(vcpu, size, port);
}

static int nmi_interception(struct vcpu_svm *svm)
{
	return 1;
}

static int intr_interception(struct vcpu_svm *svm)
{
	++svm->vcpu.stat.irq_exits;
	return 1;
}

static int nop_on_interception(struct vcpu_svm *svm)
{
	return 1;
}

static int halt_interception(struct vcpu_svm *svm)
{
	svm->next_rip = kvm_rip_read(&svm->vcpu) + 1;
	skip_emulated_instruction(&svm->vcpu);
	return kvm_emulate_halt(&svm->vcpu);
}

static int vmmcall_interception(struct vcpu_svm *svm)
{
	svm->next_rip = kvm_rip_read(&svm->vcpu) + 3;
	skip_emulated_instruction(&svm->vcpu);
	kvm_emulate_hypercall(&svm->vcpu);
	return 1;
}

static unsigned long nested_svm_get_tdp_cr3(struct kvm_vcpu *vcpu)
{
	struct vcpu_svm *svm = to_svm(vcpu);

	return svm->nested.nested_cr3;
}

static u64 nested_svm_get_tdp_pdptr(struct kvm_vcpu *vcpu, int index)
{
	struct vcpu_svm *svm = to_svm(vcpu);
	u64 cr3 = svm->nested.nested_cr3;
	u64 pdpte;
	int ret;

	ret = kvm_read_guest_page(vcpu->kvm, gpa_to_gfn(cr3), &pdpte,
				  offset_in_page(cr3) + index * 8, 8);
	if (ret)
		return 0;
	return pdpte;
}

static void nested_svm_set_tdp_cr3(struct kvm_vcpu *vcpu,
				   unsigned long root)
{
	struct vcpu_svm *svm = to_svm(vcpu);

	svm->vmcb->control.nested_cr3 = root;
	mark_dirty(svm->vmcb, VMCB_NPT);
	svm_flush_tlb(vcpu);
}

static void nested_svm_inject_npf_exit(struct kvm_vcpu *vcpu,
				       struct x86_exception *fault)
{
	struct vcpu_svm *svm = to_svm(vcpu);

	svm->vmcb->control.exit_code = SVM_EXIT_NPF;
	svm->vmcb->control.exit_code_hi = 0;
	svm->vmcb->control.exit_info_1 = fault->error_code;
	svm->vmcb->control.exit_info_2 = fault->address;

	nested_svm_vmexit(svm);
}

static int nested_svm_init_mmu_context(struct kvm_vcpu *vcpu)
{
	int r;

	r = kvm_init_shadow_mmu(vcpu, &vcpu->arch.mmu);

	vcpu->arch.mmu.set_cr3           = nested_svm_set_tdp_cr3;
	vcpu->arch.mmu.get_cr3           = nested_svm_get_tdp_cr3;
	vcpu->arch.mmu.get_pdptr         = nested_svm_get_tdp_pdptr;
	vcpu->arch.mmu.inject_page_fault = nested_svm_inject_npf_exit;
	vcpu->arch.mmu.shadow_root_level = get_npt_level();
	vcpu->arch.walk_mmu              = &vcpu->arch.nested_mmu;

	return r;
}

static void nested_svm_uninit_mmu_context(struct kvm_vcpu *vcpu)
{
	vcpu->arch.walk_mmu = &vcpu->arch.mmu;
}

static int nested_svm_check_permissions(struct vcpu_svm *svm)
{
	if (!(svm->vcpu.arch.efer & EFER_SVME)
	    || !is_paging(&svm->vcpu)) {
		kvm_queue_exception(&svm->vcpu, UD_VECTOR);
		return 1;
	}

	if (svm->vmcb->save.cpl) {
		kvm_inject_gp(&svm->vcpu, 0);
		return 1;
	}

       return 0;
}

static int nested_svm_check_exception(struct vcpu_svm *svm, unsigned nr,
				      bool has_error_code, u32 error_code)
{
	int vmexit;

	if (!is_guest_mode(&svm->vcpu))
		return 0;

	svm->vmcb->control.exit_code = SVM_EXIT_EXCP_BASE + nr;
	svm->vmcb->control.exit_code_hi = 0;
	svm->vmcb->control.exit_info_1 = error_code;
	svm->vmcb->control.exit_info_2 = svm->vcpu.arch.cr2;

	vmexit = nested_svm_intercept(svm);
	if (vmexit == NESTED_EXIT_DONE)
		svm->nested.exit_required = true;

	return vmexit;
}

/* This function returns true if it is save to enable the irq window */
static inline bool nested_svm_intr(struct vcpu_svm *svm)
{
	if (!is_guest_mode(&svm->vcpu))
		return true;

	if (!(svm->vcpu.arch.hflags & HF_VINTR_MASK))
		return true;

	if (!(svm->vcpu.arch.hflags & HF_HIF_MASK))
		return false;

	/*
	 * if vmexit was already requested (by intercepted exception
	 * for instance) do not overwrite it with "external interrupt"
	 * vmexit.
	 */
	if (svm->nested.exit_required)
		return false;

	svm->vmcb->control.exit_code   = SVM_EXIT_INTR;
	svm->vmcb->control.exit_info_1 = 0;
	svm->vmcb->control.exit_info_2 = 0;

	if (svm->nested.intercept & 1ULL) {
		/*
		 * The #vmexit can't be emulated here directly because this
		 * code path runs with irqs and preemtion disabled. A
		 * #vmexit emulation might sleep. Only signal request for
		 * the #vmexit here.
		 */
		svm->nested.exit_required = true;
		trace_kvm_nested_intr_vmexit(svm->vmcb->save.rip);
		return false;
	}

	return true;
}

/* This function returns true if it is save to enable the nmi window */
static inline bool nested_svm_nmi(struct vcpu_svm *svm)
{
	if (!is_guest_mode(&svm->vcpu))
		return true;

	if (!(svm->nested.intercept & (1ULL << INTERCEPT_NMI)))
		return true;

	svm->vmcb->control.exit_code = SVM_EXIT_NMI;
	svm->nested.exit_required = true;

	return false;
}

static void *nested_svm_map(struct vcpu_svm *svm, u64 gpa, struct page **_page)
{
	struct page *page;

	might_sleep();

	page = gfn_to_page(svm->vcpu.kvm, gpa >> PAGE_SHIFT);
	if (is_error_page(page))
		goto error;

	*_page = page;

	return kmap(page);

error:
	kvm_release_page_clean(page);
	kvm_inject_gp(&svm->vcpu, 0);

	return NULL;
}

static void nested_svm_unmap(struct page *page)
{
	kunmap(page);
	kvm_release_page_dirty(page);
}

static int nested_svm_intercept_ioio(struct vcpu_svm *svm)
{
	unsigned port;
	u8 val, bit;
	u64 gpa;

	if (!(svm->nested.intercept & (1ULL << INTERCEPT_IOIO_PROT)))
		return NESTED_EXIT_HOST;

	port = svm->vmcb->control.exit_info_1 >> 16;
	gpa  = svm->nested.vmcb_iopm + (port / 8);
	bit  = port % 8;
	val  = 0;

	if (kvm_read_guest(svm->vcpu.kvm, gpa, &val, 1))
		val &= (1 << bit);

	return val ? NESTED_EXIT_DONE : NESTED_EXIT_HOST;
}

static int nested_svm_exit_handled_msr(struct vcpu_svm *svm)
{
	u32 offset, msr, value;
	int write, mask;

	if (!(svm->nested.intercept & (1ULL << INTERCEPT_MSR_PROT)))
		return NESTED_EXIT_HOST;

	msr    = svm->vcpu.arch.regs[VCPU_REGS_RCX];
	offset = svm_msrpm_offset(msr);
	write  = svm->vmcb->control.exit_info_1 & 1;
	mask   = 1 << ((2 * (msr & 0xf)) + write);

	if (offset == MSR_INVALID)
		return NESTED_EXIT_DONE;

	/* Offset is in 32 bit units but need in 8 bit units */
	offset *= 4;

	if (kvm_read_guest(svm->vcpu.kvm, svm->nested.vmcb_msrpm + offset, &value, 4))
		return NESTED_EXIT_DONE;

	return (value & mask) ? NESTED_EXIT_DONE : NESTED_EXIT_HOST;
}

static int nested_svm_exit_special(struct vcpu_svm *svm)
{
	u32 exit_code = svm->vmcb->control.exit_code;

	switch (exit_code) {
	case SVM_EXIT_INTR:
	case SVM_EXIT_NMI:
	case SVM_EXIT_EXCP_BASE + MC_VECTOR:
		return NESTED_EXIT_HOST;
	case SVM_EXIT_NPF:
		/* For now we are always handling NPFs when using them */
		if (npt_enabled)
			return NESTED_EXIT_HOST;
		break;
	case SVM_EXIT_EXCP_BASE + PF_VECTOR:
		/* When we're shadowing, trap PFs, but not async PF */
		if (!npt_enabled && svm->apf_reason == 0)
			return NESTED_EXIT_HOST;
		break;
	case SVM_EXIT_EXCP_BASE + NM_VECTOR:
		nm_interception(svm);
		break;
	default:
		break;
	}

	return NESTED_EXIT_CONTINUE;
}

/*
 * If this function returns true, this #vmexit was already handled
 */
static int nested_svm_intercept(struct vcpu_svm *svm)
{
	u32 exit_code = svm->vmcb->control.exit_code;
	int vmexit = NESTED_EXIT_HOST;

	switch (exit_code) {
	case SVM_EXIT_MSR:
		vmexit = nested_svm_exit_handled_msr(svm);
		break;
	case SVM_EXIT_IOIO:
		vmexit = nested_svm_intercept_ioio(svm);
		break;
	case SVM_EXIT_READ_CR0 ... SVM_EXIT_WRITE_CR8: {
		u32 bit = 1U << (exit_code - SVM_EXIT_READ_CR0);
		if (svm->nested.intercept_cr & bit)
			vmexit = NESTED_EXIT_DONE;
		break;
	}
	case SVM_EXIT_READ_DR0 ... SVM_EXIT_WRITE_DR7: {
		u32 bit = 1U << (exit_code - SVM_EXIT_READ_DR0);
		if (svm->nested.intercept_dr & bit)
			vmexit = NESTED_EXIT_DONE;
		break;
	}
	case SVM_EXIT_EXCP_BASE ... SVM_EXIT_EXCP_BASE + 0x1f: {
		u32 excp_bits = 1 << (exit_code - SVM_EXIT_EXCP_BASE);
		if (svm->nested.intercept_exceptions & excp_bits)
			vmexit = NESTED_EXIT_DONE;
		/* async page fault always cause vmexit */
		else if ((exit_code == SVM_EXIT_EXCP_BASE + PF_VECTOR) &&
			 svm->apf_reason != 0)
			vmexit = NESTED_EXIT_DONE;
		break;
	}
	case SVM_EXIT_ERR: {
		vmexit = NESTED_EXIT_DONE;
		break;
	}
	default: {
		u64 exit_bits = 1ULL << (exit_code - SVM_EXIT_INTR);
		if (svm->nested.intercept & exit_bits)
			vmexit = NESTED_EXIT_DONE;
	}
	}

	return vmexit;
}

static int nested_svm_exit_handled(struct vcpu_svm *svm)
{
	int vmexit;

	vmexit = nested_svm_intercept(svm);

	if (vmexit == NESTED_EXIT_DONE)
		nested_svm_vmexit(svm);

	return vmexit;
}

static inline void copy_vmcb_control_area(struct vmcb *dst_vmcb, struct vmcb *from_vmcb)
{
	struct vmcb_control_area *dst  = &dst_vmcb->control;
	struct vmcb_control_area *from = &from_vmcb->control;

	dst->intercept_cr         = from->intercept_cr;
	dst->intercept_dr         = from->intercept_dr;
	dst->intercept_exceptions = from->intercept_exceptions;
	dst->intercept            = from->intercept;
	dst->iopm_base_pa         = from->iopm_base_pa;
	dst->msrpm_base_pa        = from->msrpm_base_pa;
	dst->tsc_offset           = from->tsc_offset;
	dst->asid                 = from->asid;
	dst->tlb_ctl              = from->tlb_ctl;
	dst->int_ctl              = from->int_ctl;
	dst->int_vector           = from->int_vector;
	dst->int_state            = from->int_state;
	dst->exit_code            = from->exit_code;
	dst->exit_code_hi         = from->exit_code_hi;
	dst->exit_info_1          = from->exit_info_1;
	dst->exit_info_2          = from->exit_info_2;
	dst->exit_int_info        = from->exit_int_info;
	dst->exit_int_info_err    = from->exit_int_info_err;
	dst->nested_ctl           = from->nested_ctl;
	dst->event_inj            = from->event_inj;
	dst->event_inj_err        = from->event_inj_err;
	dst->nested_cr3           = from->nested_cr3;
	dst->lbr_ctl              = from->lbr_ctl;
}

static int nested_svm_vmexit(struct vcpu_svm *svm)
{
	struct vmcb *nested_vmcb;
	struct vmcb *hsave = svm->nested.hsave;
	struct vmcb *vmcb = svm->vmcb;
	struct page *page;

	trace_kvm_nested_vmexit_inject(vmcb->control.exit_code,
				       vmcb->control.exit_info_1,
				       vmcb->control.exit_info_2,
				       vmcb->control.exit_int_info,
				       vmcb->control.exit_int_info_err,
				       KVM_ISA_SVM);

	nested_vmcb = nested_svm_map(svm, svm->nested.vmcb, &page);
	if (!nested_vmcb)
		return 1;

	/* Exit Guest-Mode */
	leave_guest_mode(&svm->vcpu);
	svm->nested.vmcb = 0;

	/* Give the current vmcb to the guest */
	disable_gif(svm);

	nested_vmcb->save.es     = vmcb->save.es;
	nested_vmcb->save.cs     = vmcb->save.cs;
	nested_vmcb->save.ss     = vmcb->save.ss;
	nested_vmcb->save.ds     = vmcb->save.ds;
	nested_vmcb->save.gdtr   = vmcb->save.gdtr;
	nested_vmcb->save.idtr   = vmcb->save.idtr;
	nested_vmcb->save.efer   = svm->vcpu.arch.efer;
	nested_vmcb->save.cr0    = kvm_read_cr0(&svm->vcpu);
	nested_vmcb->save.cr3    = kvm_read_cr3(&svm->vcpu);
	nested_vmcb->save.cr2    = vmcb->save.cr2;
	nested_vmcb->save.cr4    = svm->vcpu.arch.cr4;
	nested_vmcb->save.rflags = kvm_get_rflags(&svm->vcpu);
	nested_vmcb->save.rip    = vmcb->save.rip;
	nested_vmcb->save.rsp    = vmcb->save.rsp;
	nested_vmcb->save.rax    = vmcb->save.rax;
	nested_vmcb->save.dr7    = vmcb->save.dr7;
	nested_vmcb->save.dr6    = vmcb->save.dr6;
	nested_vmcb->save.cpl    = vmcb->save.cpl;

	nested_vmcb->control.int_ctl           = vmcb->control.int_ctl;
	nested_vmcb->control.int_vector        = vmcb->control.int_vector;
	nested_vmcb->control.int_state         = vmcb->control.int_state;
	nested_vmcb->control.exit_code         = vmcb->control.exit_code;
	nested_vmcb->control.exit_code_hi      = vmcb->control.exit_code_hi;
	nested_vmcb->control.exit_info_1       = vmcb->control.exit_info_1;
	nested_vmcb->control.exit_info_2       = vmcb->control.exit_info_2;
	nested_vmcb->control.exit_int_info     = vmcb->control.exit_int_info;
	nested_vmcb->control.exit_int_info_err = vmcb->control.exit_int_info_err;
	nested_vmcb->control.next_rip          = vmcb->control.next_rip;

	/*
	 * If we emulate a VMRUN/#VMEXIT in the same host #vmexit cycle we have
	 * to make sure that we do not lose injected events. So check event_inj
	 * here and copy it to exit_int_info if it is valid.
	 * Exit_int_info and event_inj can't be both valid because the case
	 * below only happens on a VMRUN instruction intercept which has
	 * no valid exit_int_info set.
	 */
	if (vmcb->control.event_inj & SVM_EVTINJ_VALID) {
		struct vmcb_control_area *nc = &nested_vmcb->control;

		nc->exit_int_info     = vmcb->control.event_inj;
		nc->exit_int_info_err = vmcb->control.event_inj_err;
	}

	nested_vmcb->control.tlb_ctl           = 0;
	nested_vmcb->control.event_inj         = 0;
	nested_vmcb->control.event_inj_err     = 0;

	/* We always set V_INTR_MASKING and remember the old value in hflags */
	if (!(svm->vcpu.arch.hflags & HF_VINTR_MASK))
		nested_vmcb->control.int_ctl &= ~V_INTR_MASKING_MASK;

	/* Restore the original control entries */
	copy_vmcb_control_area(vmcb, hsave);

	kvm_clear_exception_queue(&svm->vcpu);
	kvm_clear_interrupt_queue(&svm->vcpu);

	svm->nested.nested_cr3 = 0;

	/* Restore selected save entries */
	svm->vmcb->save.es = hsave->save.es;
	svm->vmcb->save.cs = hsave->save.cs;
	svm->vmcb->save.ss = hsave->save.ss;
	svm->vmcb->save.ds = hsave->save.ds;
	svm->vmcb->save.gdtr = hsave->save.gdtr;
	svm->vmcb->save.idtr = hsave->save.idtr;
	kvm_set_rflags(&svm->vcpu, hsave->save.rflags);
	svm_set_efer(&svm->vcpu, hsave->save.efer);
	svm_set_cr0(&svm->vcpu, hsave->save.cr0 | X86_CR0_PE);
	svm_set_cr4(&svm->vcpu, hsave->save.cr4);
	if (npt_enabled) {
		svm->vmcb->save.cr3 = hsave->save.cr3;
		svm->vcpu.arch.cr3 = hsave->save.cr3;
	} else {
		(void)kvm_set_cr3(&svm->vcpu, hsave->save.cr3);
	}
	kvm_register_write(&svm->vcpu, VCPU_REGS_RAX, hsave->save.rax);
	kvm_register_write(&svm->vcpu, VCPU_REGS_RSP, hsave->save.rsp);
	kvm_register_write(&svm->vcpu, VCPU_REGS_RIP, hsave->save.rip);
	svm->vmcb->save.dr7 = 0;
	svm->vmcb->save.cpl = 0;
	svm->vmcb->control.exit_int_info = 0;

	mark_all_dirty(svm->vmcb);

	nested_svm_unmap(page);

	nested_svm_uninit_mmu_context(&svm->vcpu);
	kvm_mmu_reset_context(&svm->vcpu);
	kvm_mmu_load(&svm->vcpu);

	return 0;
}

static bool nested_svm_vmrun_msrpm(struct vcpu_svm *svm)
{
	/*
	 * This function merges the msr permission bitmaps of kvm and the
	 * nested vmcb. It is omptimized in that it only merges the parts where
	 * the kvm msr permission bitmap may contain zero bits
	 */
	int i;

	if (!(svm->nested.intercept & (1ULL << INTERCEPT_MSR_PROT)))
		return true;

	for (i = 0; i < MSRPM_OFFSETS; i++) {
		u32 value, p;
		u64 offset;

		if (msrpm_offsets[i] == 0xffffffff)
			break;

		p      = msrpm_offsets[i];
		offset = svm->nested.vmcb_msrpm + (p * 4);

		if (kvm_read_guest(svm->vcpu.kvm, offset, &value, 4))
			return false;

		svm->nested.msrpm[p] = svm->msrpm[p] | value;
	}

	svm->vmcb->control.msrpm_base_pa = __pa(svm->nested.msrpm);

	return true;
}

static bool nested_vmcb_checks(struct vmcb *vmcb)
{
	if ((vmcb->control.intercept & (1ULL << INTERCEPT_VMRUN)) == 0)
		return false;

	if (vmcb->control.asid == 0)
		return false;

	if (vmcb->control.nested_ctl && !npt_enabled)
		return false;

	return true;
}

static bool nested_svm_vmrun(struct vcpu_svm *svm)
{
	struct vmcb *nested_vmcb;
	struct vmcb *hsave = svm->nested.hsave;
	struct vmcb *vmcb = svm->vmcb;
	struct page *page;
	u64 vmcb_gpa;

	vmcb_gpa = svm->vmcb->save.rax;

	nested_vmcb = nested_svm_map(svm, svm->vmcb->save.rax, &page);
	if (!nested_vmcb)
		return false;

	if (!nested_vmcb_checks(nested_vmcb)) {
		nested_vmcb->control.exit_code    = SVM_EXIT_ERR;
		nested_vmcb->control.exit_code_hi = 0;
		nested_vmcb->control.exit_info_1  = 0;
		nested_vmcb->control.exit_info_2  = 0;

		nested_svm_unmap(page);

		return false;
	}

	trace_kvm_nested_vmrun(svm->vmcb->save.rip, vmcb_gpa,
			       nested_vmcb->save.rip,
			       nested_vmcb->control.int_ctl,
			       nested_vmcb->control.event_inj,
			       nested_vmcb->control.nested_ctl);

	trace_kvm_nested_intercepts(nested_vmcb->control.intercept_cr & 0xffff,
				    nested_vmcb->control.intercept_cr >> 16,
				    nested_vmcb->control.intercept_exceptions,
				    nested_vmcb->control.intercept);

	/* Clear internal status */
	kvm_clear_exception_queue(&svm->vcpu);
	kvm_clear_interrupt_queue(&svm->vcpu);

	/*
	 * Save the old vmcb, so we don't need to pick what we save, but can
	 * restore everything when a VMEXIT occurs
	 */
	hsave->save.es     = vmcb->save.es;
	hsave->save.cs     = vmcb->save.cs;
	hsave->save.ss     = vmcb->save.ss;
	hsave->save.ds     = vmcb->save.ds;
	hsave->save.gdtr   = vmcb->save.gdtr;
	hsave->save.idtr   = vmcb->save.idtr;
	hsave->save.efer   = svm->vcpu.arch.efer;
	hsave->save.cr0    = kvm_read_cr0(&svm->vcpu);
	hsave->save.cr4    = svm->vcpu.arch.cr4;
	hsave->save.rflags = kvm_get_rflags(&svm->vcpu);
	hsave->save.rip    = kvm_rip_read(&svm->vcpu);
	hsave->save.rsp    = vmcb->save.rsp;
	hsave->save.rax    = vmcb->save.rax;
	if (npt_enabled)
		hsave->save.cr3    = vmcb->save.cr3;
	else
		hsave->save.cr3    = kvm_read_cr3(&svm->vcpu);

	copy_vmcb_control_area(hsave, vmcb);

	if (kvm_get_rflags(&svm->vcpu) & X86_EFLAGS_IF)
		svm->vcpu.arch.hflags |= HF_HIF_MASK;
	else
		svm->vcpu.arch.hflags &= ~HF_HIF_MASK;

	if (nested_vmcb->control.nested_ctl) {
		kvm_mmu_unload(&svm->vcpu);
		svm->nested.nested_cr3 = nested_vmcb->control.nested_cr3;
		nested_svm_init_mmu_context(&svm->vcpu);
	}

	/* Load the nested guest state */
	svm->vmcb->save.es = nested_vmcb->save.es;
	svm->vmcb->save.cs = nested_vmcb->save.cs;
	svm->vmcb->save.ss = nested_vmcb->save.ss;
	svm->vmcb->save.ds = nested_vmcb->save.ds;
	svm->vmcb->save.gdtr = nested_vmcb->save.gdtr;
	svm->vmcb->save.idtr = nested_vmcb->save.idtr;
	kvm_set_rflags(&svm->vcpu, nested_vmcb->save.rflags);
	svm_set_efer(&svm->vcpu, nested_vmcb->save.efer);
	svm_set_cr0(&svm->vcpu, nested_vmcb->save.cr0);
	svm_set_cr4(&svm->vcpu, nested_vmcb->save.cr4);
	if (npt_enabled) {
		svm->vmcb->save.cr3 = nested_vmcb->save.cr3;
		svm->vcpu.arch.cr3 = nested_vmcb->save.cr3;
	} else
		(void)kvm_set_cr3(&svm->vcpu, nested_vmcb->save.cr3);

	/* Guest paging mode is active - reset mmu */
	kvm_mmu_reset_context(&svm->vcpu);

	svm->vmcb->save.cr2 = svm->vcpu.arch.cr2 = nested_vmcb->save.cr2;
	kvm_register_write(&svm->vcpu, VCPU_REGS_RAX, nested_vmcb->save.rax);
	kvm_register_write(&svm->vcpu, VCPU_REGS_RSP, nested_vmcb->save.rsp);
	kvm_register_write(&svm->vcpu, VCPU_REGS_RIP, nested_vmcb->save.rip);

	/* In case we don't even reach vcpu_run, the fields are not updated */
	svm->vmcb->save.rax = nested_vmcb->save.rax;
	svm->vmcb->save.rsp = nested_vmcb->save.rsp;
	svm->vmcb->save.rip = nested_vmcb->save.rip;
	svm->vmcb->save.dr7 = nested_vmcb->save.dr7;
	svm->vmcb->save.dr6 = nested_vmcb->save.dr6;
	svm->vmcb->save.cpl = nested_vmcb->save.cpl;

	svm->nested.vmcb_msrpm = nested_vmcb->control.msrpm_base_pa & ~0x0fffULL;
	svm->nested.vmcb_iopm  = nested_vmcb->control.iopm_base_pa  & ~0x0fffULL;

	/* cache intercepts */
	svm->nested.intercept_cr         = nested_vmcb->control.intercept_cr;
	svm->nested.intercept_dr         = nested_vmcb->control.intercept_dr;
	svm->nested.intercept_exceptions = nested_vmcb->control.intercept_exceptions;
	svm->nested.intercept            = nested_vmcb->control.intercept;

	svm_flush_tlb(&svm->vcpu);
	svm->vmcb->control.int_ctl = nested_vmcb->control.int_ctl | V_INTR_MASKING_MASK;
	if (nested_vmcb->control.int_ctl & V_INTR_MASKING_MASK)
		svm->vcpu.arch.hflags |= HF_VINTR_MASK;
	else
		svm->vcpu.arch.hflags &= ~HF_VINTR_MASK;

	if (svm->vcpu.arch.hflags & HF_VINTR_MASK) {
		/* We only want the cr8 intercept bits of the guest */
		clr_cr_intercept(svm, INTERCEPT_CR8_READ);
		clr_cr_intercept(svm, INTERCEPT_CR8_WRITE);
	}

	/* We don't want to see VMMCALLs from a nested guest */
	clr_intercept(svm, INTERCEPT_VMMCALL);

	svm->vmcb->control.lbr_ctl = nested_vmcb->control.lbr_ctl;
	svm->vmcb->control.int_vector = nested_vmcb->control.int_vector;
	svm->vmcb->control.int_state = nested_vmcb->control.int_state;
	svm->vmcb->control.tsc_offset += nested_vmcb->control.tsc_offset;
	svm->vmcb->control.event_inj = nested_vmcb->control.event_inj;
	svm->vmcb->control.event_inj_err = nested_vmcb->control.event_inj_err;

	nested_svm_unmap(page);

	/* Enter Guest-Mode */
	enter_guest_mode(&svm->vcpu);

	/*
	 * Merge guest and host intercepts - must be called  with vcpu in
	 * guest-mode to take affect here
	 */
	recalc_intercepts(svm);

	svm->nested.vmcb = vmcb_gpa;

	enable_gif(svm);

	mark_all_dirty(svm->vmcb);

	return true;
}

static void nested_svm_vmloadsave(struct vmcb *from_vmcb, struct vmcb *to_vmcb)
{
	to_vmcb->save.fs = from_vmcb->save.fs;
	to_vmcb->save.gs = from_vmcb->save.gs;
	to_vmcb->save.tr = from_vmcb->save.tr;
	to_vmcb->save.ldtr = from_vmcb->save.ldtr;
	to_vmcb->save.kernel_gs_base = from_vmcb->save.kernel_gs_base;
	to_vmcb->save.star = from_vmcb->save.star;
	to_vmcb->save.lstar = from_vmcb->save.lstar;
	to_vmcb->save.cstar = from_vmcb->save.cstar;
	to_vmcb->save.sfmask = from_vmcb->save.sfmask;
	to_vmcb->save.sysenter_cs = from_vmcb->save.sysenter_cs;
	to_vmcb->save.sysenter_esp = from_vmcb->save.sysenter_esp;
	to_vmcb->save.sysenter_eip = from_vmcb->save.sysenter_eip;
}

static int vmload_interception(struct vcpu_svm *svm)
{
	struct vmcb *nested_vmcb;
	struct page *page;

	if (nested_svm_check_permissions(svm))
		return 1;

	nested_vmcb = nested_svm_map(svm, svm->vmcb->save.rax, &page);
	if (!nested_vmcb)
		return 1;

	svm->next_rip = kvm_rip_read(&svm->vcpu) + 3;
	skip_emulated_instruction(&svm->vcpu);

	nested_svm_vmloadsave(nested_vmcb, svm->vmcb);
	nested_svm_unmap(page);

	return 1;
}

static int vmsave_interception(struct vcpu_svm *svm)
{
	struct vmcb *nested_vmcb;
	struct page *page;

	if (nested_svm_check_permissions(svm))
		return 1;

	nested_vmcb = nested_svm_map(svm, svm->vmcb->save.rax, &page);
	if (!nested_vmcb)
		return 1;

	svm->next_rip = kvm_rip_read(&svm->vcpu) + 3;
	skip_emulated_instruction(&svm->vcpu);

	nested_svm_vmloadsave(svm->vmcb, nested_vmcb);
	nested_svm_unmap(page);

	return 1;
}

static int vmrun_interception(struct vcpu_svm *svm)
{
	if (nested_svm_check_permissions(svm))
		return 1;

	/* Save rip after vmrun instruction */
	kvm_rip_write(&svm->vcpu, kvm_rip_read(&svm->vcpu) + 3);

	if (!nested_svm_vmrun(svm))
		return 1;

	if (!nested_svm_vmrun_msrpm(svm))
		goto failed;

	return 1;

failed:

	svm->vmcb->control.exit_code    = SVM_EXIT_ERR;
	svm->vmcb->control.exit_code_hi = 0;
	svm->vmcb->control.exit_info_1  = 0;
	svm->vmcb->control.exit_info_2  = 0;

	nested_svm_vmexit(svm);

	return 1;
}

static int stgi_interception(struct vcpu_svm *svm)
{
	if (nested_svm_check_permissions(svm))
		return 1;

	svm->next_rip = kvm_rip_read(&svm->vcpu) + 3;
	skip_emulated_instruction(&svm->vcpu);
	kvm_make_request(KVM_REQ_EVENT, &svm->vcpu);

	enable_gif(svm);

	return 1;
}

static int clgi_interception(struct vcpu_svm *svm)
{
	if (nested_svm_check_permissions(svm))
		return 1;

	svm->next_rip = kvm_rip_read(&svm->vcpu) + 3;
	skip_emulated_instruction(&svm->vcpu);

	disable_gif(svm);

	/* After a CLGI no interrupts should come */
	svm_clear_vintr(svm);
	svm->vmcb->control.int_ctl &= ~V_IRQ_MASK;

	mark_dirty(svm->vmcb, VMCB_INTR);

	return 1;
}

static int invlpga_interception(struct vcpu_svm *svm)
{
	struct kvm_vcpu *vcpu = &svm->vcpu;

	trace_kvm_invlpga(svm->vmcb->save.rip, vcpu->arch.regs[VCPU_REGS_RCX],
			  vcpu->arch.regs[VCPU_REGS_RAX]);

	/* Let's treat INVLPGA the same as INVLPG (can be optimized!) */
	kvm_mmu_invlpg(vcpu, vcpu->arch.regs[VCPU_REGS_RAX]);

	svm->next_rip = kvm_rip_read(&svm->vcpu) + 3;
	skip_emulated_instruction(&svm->vcpu);
	return 1;
}

static int skinit_interception(struct vcpu_svm *svm)
{
	trace_kvm_skinit(svm->vmcb->save.rip, svm->vcpu.arch.regs[VCPU_REGS_RAX]);

	kvm_queue_exception(&svm->vcpu, UD_VECTOR);
	return 1;
}

static int xsetbv_interception(struct vcpu_svm *svm)
{
	u64 new_bv = kvm_read_edx_eax(&svm->vcpu);
	u32 index = kvm_register_read(&svm->vcpu, VCPU_REGS_RCX);

	if (kvm_set_xcr(&svm->vcpu, index, new_bv) == 0) {
		svm->next_rip = kvm_rip_read(&svm->vcpu) + 3;
		skip_emulated_instruction(&svm->vcpu);
	}

	return 1;
}

static int invalid_op_interception(struct vcpu_svm *svm)
{
	kvm_queue_exception(&svm->vcpu, UD_VECTOR);
	return 1;
}

static int task_switch_interception(struct vcpu_svm *svm)
{
	u16 tss_selector;
	int reason;
	int int_type = svm->vmcb->control.exit_int_info &
		SVM_EXITINTINFO_TYPE_MASK;
	int int_vec = svm->vmcb->control.exit_int_info & SVM_EVTINJ_VEC_MASK;
	uint32_t type =
		svm->vmcb->control.exit_int_info & SVM_EXITINTINFO_TYPE_MASK;
	uint32_t idt_v =
		svm->vmcb->control.exit_int_info & SVM_EXITINTINFO_VALID;
	bool has_error_code = false;
	u32 error_code = 0;

	tss_selector = (u16)svm->vmcb->control.exit_info_1;

	if (svm->vmcb->control.exit_info_2 &
	    (1ULL << SVM_EXITINFOSHIFT_TS_REASON_IRET))
		reason = TASK_SWITCH_IRET;
	else if (svm->vmcb->control.exit_info_2 &
		 (1ULL << SVM_EXITINFOSHIFT_TS_REASON_JMP))
		reason = TASK_SWITCH_JMP;
	else if (idt_v)
		reason = TASK_SWITCH_GATE;
	else
		reason = TASK_SWITCH_CALL;

	if (reason == TASK_SWITCH_GATE) {
		switch (type) {
		case SVM_EXITINTINFO_TYPE_NMI:
			svm->vcpu.arch.nmi_injected = false;
			break;
		case SVM_EXITINTINFO_TYPE_EXEPT:
			if (svm->vmcb->control.exit_info_2 &
			    (1ULL << SVM_EXITINFOSHIFT_TS_HAS_ERROR_CODE)) {
				has_error_code = true;
				error_code =
					(u32)svm->vmcb->control.exit_info_2;
			}
			kvm_clear_exception_queue(&svm->vcpu);
			break;
		case SVM_EXITINTINFO_TYPE_INTR:
			kvm_clear_interrupt_queue(&svm->vcpu);
			break;
		default:
			break;
		}
	}

	if (reason != TASK_SWITCH_GATE ||
	    int_type == SVM_EXITINTINFO_TYPE_SOFT ||
	    (int_type == SVM_EXITINTINFO_TYPE_EXEPT &&
	     (int_vec == OF_VECTOR || int_vec == BP_VECTOR)))
		skip_emulated_instruction(&svm->vcpu);

	if (kvm_task_switch(&svm->vcpu, tss_selector, reason,
				has_error_code, error_code) == EMULATE_FAIL) {
		svm->vcpu.run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
		svm->vcpu.run->internal.suberror = KVM_INTERNAL_ERROR_EMULATION;
		svm->vcpu.run->internal.ndata = 0;
		return 0;
	}
	return 1;
}

static int cpuid_interception(struct vcpu_svm *svm)
{
	svm->next_rip = kvm_rip_read(&svm->vcpu) + 2;
	kvm_emulate_cpuid(&svm->vcpu);
	return 1;
}

static int iret_interception(struct vcpu_svm *svm)
{
	++svm->vcpu.stat.nmi_window_exits;
	clr_intercept(svm, INTERCEPT_IRET);
	svm->vcpu.arch.hflags |= HF_IRET_MASK;
	svm->nmi_iret_rip = kvm_rip_read(&svm->vcpu);
	return 1;
}

static int invlpg_interception(struct vcpu_svm *svm)
{
	if (!static_cpu_has(X86_FEATURE_DECODEASSISTS))
		return emulate_instruction(&svm->vcpu, 0) == EMULATE_DONE;

	kvm_mmu_invlpg(&svm->vcpu, svm->vmcb->control.exit_info_1);
	skip_emulated_instruction(&svm->vcpu);
	return 1;
}

static int emulate_on_interception(struct vcpu_svm *svm)
{
	return emulate_instruction(&svm->vcpu, 0) == EMULATE_DONE;
}

bool check_selective_cr0_intercepted(struct vcpu_svm *svm, unsigned long val)
{
	unsigned long cr0 = svm->vcpu.arch.cr0;
	bool ret = false;
	u64 intercept;

	intercept = svm->nested.intercept;

	if (!is_guest_mode(&svm->vcpu) ||
	    (!(intercept & (1ULL << INTERCEPT_SELECTIVE_CR0))))
		return false;

	cr0 &= ~SVM_CR0_SELECTIVE_MASK;
	val &= ~SVM_CR0_SELECTIVE_MASK;

	if (cr0 ^ val) {
		svm->vmcb->control.exit_code = SVM_EXIT_CR0_SEL_WRITE;
		ret = (nested_svm_exit_handled(svm) == NESTED_EXIT_DONE);
	}

	return ret;
}

#define CR_VALID (1ULL << 63)

static int cr_interception(struct vcpu_svm *svm)
{
	int reg, cr;
	unsigned long val;
	int err;

	if (!static_cpu_has(X86_FEATURE_DECODEASSISTS))
		return emulate_on_interception(svm);

	if (unlikely((svm->vmcb->control.exit_info_1 & CR_VALID) == 0))
		return emulate_on_interception(svm);

	reg = svm->vmcb->control.exit_info_1 & SVM_EXITINFO_REG_MASK;
	cr = svm->vmcb->control.exit_code - SVM_EXIT_READ_CR0;

	err = 0;
	if (cr >= 16) { /* mov to cr */
		cr -= 16;
		val = kvm_register_read(&svm->vcpu, reg);
		switch (cr) {
		case 0:
			if (!check_selective_cr0_intercepted(svm, val))
				err = kvm_set_cr0(&svm->vcpu, val);
			else
				return 1;

			break;
		case 3:
			err = kvm_set_cr3(&svm->vcpu, val);
			break;
		case 4:
			err = kvm_set_cr4(&svm->vcpu, val);
			break;
		case 8:
			err = kvm_set_cr8(&svm->vcpu, val);
			break;
		default:
			WARN(1, "unhandled write to CR%d", cr);
			kvm_queue_exception(&svm->vcpu, UD_VECTOR);
			return 1;
		}
	} else { /* mov from cr */
		switch (cr) {
		case 0:
			val = kvm_read_cr0(&svm->vcpu);
			break;
		case 2:
			val = svm->vcpu.arch.cr2;
			break;
		case 3:
			val = kvm_read_cr3(&svm->vcpu);
			break;
		case 4:
			val = kvm_read_cr4(&svm->vcpu);
			break;
		case 8:
			val = kvm_get_cr8(&svm->vcpu);
			break;
		default:
			WARN(1, "unhandled read from CR%d", cr);
			kvm_queue_exception(&svm->vcpu, UD_VECTOR);
			return 1;
		}
		kvm_register_write(&svm->vcpu, reg, val);
	}
	kvm_complete_insn_gp(&svm->vcpu, err);

	return 1;
}

static int dr_interception(struct vcpu_svm *svm)
{
	int reg, dr;
	unsigned long val;
	int err;

	if (!boot_cpu_has(X86_FEATURE_DECODEASSISTS))
		return emulate_on_interception(svm);

	reg = svm->vmcb->control.exit_info_1 & SVM_EXITINFO_REG_MASK;
	dr = svm->vmcb->control.exit_code - SVM_EXIT_READ_DR0;

	if (dr >= 16) { /* mov to DRn */
		val = kvm_register_read(&svm->vcpu, reg);
		kvm_set_dr(&svm->vcpu, dr - 16, val);
	} else {
		err = kvm_get_dr(&svm->vcpu, dr, &val);
		if (!err)
			kvm_register_write(&svm->vcpu, reg, val);
	}

	skip_emulated_instruction(&svm->vcpu);

	return 1;
}

static int cr8_write_interception(struct vcpu_svm *svm)
{
	struct kvm_run *kvm_run = svm->vcpu.run;
	int r;

	u8 cr8_prev = kvm_get_cr8(&svm->vcpu);
	/* instruction emulation calls kvm_set_cr8() */
	r = cr_interception(svm);
	if (irqchip_in_kernel(svm->vcpu.kvm)) {
		clr_cr_intercept(svm, INTERCEPT_CR8_WRITE);
		return r;
	}
	if (cr8_prev <= kvm_get_cr8(&svm->vcpu))
		return r;
	kvm_run->exit_reason = KVM_EXIT_SET_TPR;
	return 0;
}

u64 svm_read_l1_tsc(struct kvm_vcpu *vcpu)
{
	struct vmcb *vmcb = get_host_vmcb(to_svm(vcpu));
	return vmcb->control.tsc_offset +
		svm_scale_tsc(vcpu, native_read_tsc());
}

static int svm_get_msr(struct kvm_vcpu *vcpu, unsigned ecx, u64 *data)
{
	struct vcpu_svm *svm = to_svm(vcpu);

	switch (ecx) {
	case MSR_IA32_TSC: {
		*data = svm->vmcb->control.tsc_offset +
			svm_scale_tsc(vcpu, native_read_tsc());

		break;
	}
	case MSR_STAR:
		*data = svm->vmcb->save.star;
		break;
#ifdef CONFIG_X86_64
	case MSR_LSTAR:
		*data = svm->vmcb->save.lstar;
		break;
	case MSR_CSTAR:
		*data = svm->vmcb->save.cstar;
		break;
	case MSR_KERNEL_GS_BASE:
		*data = svm->vmcb->save.kernel_gs_base;
		break;
	case MSR_SYSCALL_MASK:
		*data = svm->vmcb->save.sfmask;
		break;
#endif
	case MSR_IA32_SYSENTER_CS:
		*data = svm->vmcb->save.sysenter_cs;
		break;
	case MSR_IA32_SYSENTER_EIP:
		*data = svm->sysenter_eip;
		break;
	case MSR_IA32_SYSENTER_ESP:
		*data = svm->sysenter_esp;
		break;
	/*
	 * Nobody will change the following 5 values in the VMCB so we can
	 * safely return them on rdmsr. They will always be 0 until LBRV is
	 * implemented.
	 */
	case MSR_IA32_DEBUGCTLMSR:
		*data = svm->vmcb->save.dbgctl;
		break;
	case MSR_IA32_LASTBRANCHFROMIP:
		*data = svm->vmcb->save.br_from;
		break;
	case MSR_IA32_LASTBRANCHTOIP:
		*data = svm->vmcb->save.br_to;
		break;
	case MSR_IA32_LASTINTFROMIP:
		*data = svm->vmcb->save.last_excp_from;
		break;
	case MSR_IA32_LASTINTTOIP:
		*data = svm->vmcb->save.last_excp_to;
		break;
	case MSR_VM_HSAVE_PA:
		*data = svm->nested.hsave_msr;
		break;
	case MSR_VM_CR:
		*data = svm->nested.vm_cr_msr;
		break;
	case MSR_IA32_UCODE_REV:
		*data = 0x01000065;
		break;
	default:
		return kvm_get_msr_common(vcpu, ecx, data);
	}
	return 0;
}

static int rdmsr_interception(struct vcpu_svm *svm)
{
	u32 ecx = svm->vcpu.arch.regs[VCPU_REGS_RCX];
	u64 data;

	if (svm_get_msr(&svm->vcpu, ecx, &data)) {
		trace_kvm_msr_read_ex(ecx);
		kvm_inject_gp(&svm->vcpu, 0);
	} else {
		trace_kvm_msr_read(ecx, data);

		svm->vcpu.arch.regs[VCPU_REGS_RAX] = data & 0xffffffff;
		svm->vcpu.arch.regs[VCPU_REGS_RDX] = data >> 32;
		svm->next_rip = kvm_rip_read(&