]> www.pilppa.org Git - linux-2.6-omap-h63xx.git/blobdiff - arch/x86/kvm/x86.c
Merge branch 'kvm-updates/2.6.28' of git://git.kernel.org/pub/scm/linux/kernel/git...
[linux-2.6-omap-h63xx.git] / arch / x86 / kvm / x86.c
index 19afbb644c7f7649420d1bbc5a7cba209e0b3f2b..4f0677d1eae8f495147b2184474f5806c81303bd 100644 (file)
@@ -4,10 +4,14 @@
  * derived from drivers/kvm/kvm_main.c
  *
  * Copyright (C) 2006 Qumranet, Inc.
+ * Copyright (C) 2008 Qumranet, Inc.
+ * Copyright IBM Corporation, 2008
  *
  * Authors:
  *   Avi Kivity   <avi@qumranet.com>
  *   Yaniv Kamay  <yaniv@qumranet.com>
+ *   Amit Shah    <amit.shah@qumranet.com>
+ *   Ben-Ami Yassour <benami@il.ibm.com>
  *
  * This work is licensed under the terms of the GNU GPL, version 2.  See
  * the COPYING file in the top-level directory.
 #include "mmu.h"
 #include "i8254.h"
 #include "tss.h"
+#include "kvm_cache_regs.h"
+#include "x86.h"
 
 #include <linux/clocksource.h>
+#include <linux/interrupt.h>
 #include <linux/kvm.h>
 #include <linux/fs.h>
 #include <linux/vmalloc.h>
 #include <linux/module.h>
 #include <linux/mman.h>
 #include <linux/highmem.h>
+#include <linux/intel-iommu.h>
 
 #include <asm/uaccess.h>
 #include <asm/msr.h>
@@ -61,6 +69,7 @@ static int kvm_dev_ioctl_get_supported_cpuid(struct kvm_cpuid2 *cpuid,
                                    struct kvm_cpuid_entry2 __user *entries);
 
 struct kvm_x86_ops *kvm_x86_ops;
+EXPORT_SYMBOL_GPL(kvm_x86_ops);
 
 struct kvm_stats_debugfs_item debugfs_entries[] = {
        { "pf_fixed", VCPU_STAT(pf_fixed) },
@@ -83,6 +92,7 @@ struct kvm_stats_debugfs_item debugfs_entries[] = {
        { "fpu_reload", VCPU_STAT(fpu_reload) },
        { "insn_emulation", VCPU_STAT(insn_emulation) },
        { "insn_emulation_fail", VCPU_STAT(insn_emulation_fail) },
+       { "irq_injections", VCPU_STAT(irq_injections) },
        { "mmu_shadow_zapped", VM_STAT(mmu_shadow_zapped) },
        { "mmu_pte_write", VM_STAT(mmu_pte_write) },
        { "mmu_pte_updated", VM_STAT(mmu_pte_updated) },
@@ -90,12 +100,12 @@ struct kvm_stats_debugfs_item debugfs_entries[] = {
        { "mmu_flooded", VM_STAT(mmu_flooded) },
        { "mmu_recycled", VM_STAT(mmu_recycled) },
        { "mmu_cache_miss", VM_STAT(mmu_cache_miss) },
+       { "mmu_unsync", VM_STAT(mmu_unsync) },
        { "remote_tlb_flush", VM_STAT(remote_tlb_flush) },
        { "largepages", VM_STAT(lpages) },
        { NULL }
 };
 
-
 unsigned long segment_base(u16 selector)
 {
        struct descriptor_table gdt;
@@ -352,6 +362,7 @@ EXPORT_SYMBOL_GPL(kvm_set_cr4);
 void kvm_set_cr3(struct kvm_vcpu *vcpu, unsigned long cr3)
 {
        if (cr3 == vcpu->arch.cr3 && !pdptrs_changed(vcpu)) {
+               kvm_mmu_sync_roots(vcpu);
                kvm_mmu_flush_tlb(vcpu);
                return;
        }
@@ -662,6 +673,18 @@ int kvm_set_msr_common(struct kvm_vcpu *vcpu, u32 msr, u64 data)
                pr_unimpl(vcpu, "%s: MSR_IA32_MCG_CTL 0x%llx, nop\n",
                        __func__, data);
                break;
+       case MSR_IA32_DEBUGCTLMSR:
+               if (!data) {
+                       /* We support the non-activated case already */
+                       break;
+               } else if (data & ~(DEBUGCTLMSR_LBR | DEBUGCTLMSR_BTF)) {
+                       /* Values other than LBR and BTF are vendor-specific,
+                          thus reserved and should throw a #GP */
+                       return 1;
+               }
+               pr_unimpl(vcpu, "%s: MSR_IA32_DEBUGCTLMSR 0x%llx, nop\n",
+                       __func__, data);
+               break;
        case MSR_IA32_UCODE_REV:
        case MSR_IA32_UCODE_WRITE:
                break;
@@ -692,10 +715,8 @@ int kvm_set_msr_common(struct kvm_vcpu *vcpu, u32 msr, u64 data)
                /* ...but clean it before doing the actual write */
                vcpu->arch.time_offset = data & ~(PAGE_MASK | 1);
 
-               down_read(&current->mm->mmap_sem);
                vcpu->arch.time_page =
                                gfn_to_page(vcpu->kvm, data >> PAGE_SHIFT);
-               up_read(&current->mm->mmap_sem);
 
                if (is_error_page(vcpu->arch.time_page)) {
                        kvm_release_page_clean(vcpu->arch.time_page);
@@ -752,8 +773,14 @@ int kvm_get_msr_common(struct kvm_vcpu *vcpu, u32 msr, u64 *pdata)
        case MSR_IA32_MC0_MISC+8:
        case MSR_IA32_MC0_MISC+12:
        case MSR_IA32_MC0_MISC+16:
+       case MSR_IA32_MC0_MISC+20:
        case MSR_IA32_UCODE_REV:
        case MSR_IA32_EBL_CR_POWERON:
+       case MSR_IA32_DEBUGCTLMSR:
+       case MSR_IA32_LASTBRANCHFROMIP:
+       case MSR_IA32_LASTBRANCHTOIP:
+       case MSR_IA32_LASTINTFROMIP:
+       case MSR_IA32_LASTINTTOIP:
                data = 0;
                break;
        case MSR_MTRRcap:
@@ -901,6 +928,9 @@ int kvm_dev_ioctl_check_extension(long ext)
        case KVM_CAP_PV_MMU:
                r = !tdp_enabled;
                break;
+       case KVM_CAP_IOMMU:
+               r = intel_iommu_found();
+               break;
        default:
                r = 0;
                break;
@@ -1303,28 +1333,33 @@ long kvm_arch_vcpu_ioctl(struct file *filp,
        struct kvm_vcpu *vcpu = filp->private_data;
        void __user *argp = (void __user *)arg;
        int r;
+       struct kvm_lapic_state *lapic = NULL;
 
        switch (ioctl) {
        case KVM_GET_LAPIC: {
-               struct kvm_lapic_state lapic;
+               lapic = kzalloc(sizeof(struct kvm_lapic_state), GFP_KERNEL);
 
-               memset(&lapic, 0, sizeof lapic);
-               r = kvm_vcpu_ioctl_get_lapic(vcpu, &lapic);
+               r = -ENOMEM;
+               if (!lapic)
+                       goto out;
+               r = kvm_vcpu_ioctl_get_lapic(vcpu, lapic);
                if (r)
                        goto out;
                r = -EFAULT;
-               if (copy_to_user(argp, &lapic, sizeof lapic))
+               if (copy_to_user(argp, lapic, sizeof(struct kvm_lapic_state)))
                        goto out;
                r = 0;
                break;
        }
        case KVM_SET_LAPIC: {
-               struct kvm_lapic_state lapic;
-
+               lapic = kmalloc(sizeof(struct kvm_lapic_state), GFP_KERNEL);
+               r = -ENOMEM;
+               if (!lapic)
+                       goto out;
                r = -EFAULT;
-               if (copy_from_user(&lapic, argp, sizeof lapic))
+               if (copy_from_user(lapic, argp, sizeof(struct kvm_lapic_state)))
                        goto out;
-               r = kvm_vcpu_ioctl_set_lapic(vcpu, &lapic);;
+               r = kvm_vcpu_ioctl_set_lapic(vcpu, lapic);
                if (r)
                        goto out;
                r = 0;
@@ -1422,6 +1457,8 @@ long kvm_arch_vcpu_ioctl(struct file *filp,
                r = -EINVAL;
        }
 out:
+       if (lapic)
+               kfree(lapic);
        return r;
 }
 
@@ -1630,6 +1667,15 @@ long kvm_arch_vm_ioctl(struct file *filp,
        struct kvm *kvm = filp->private_data;
        void __user *argp = (void __user *)arg;
        int r = -EINVAL;
+       /*
+        * This union makes it completely explicit to gcc-3.x
+        * that these two variables' stack usage should be
+        * combined, not added together.
+        */
+       union {
+               struct kvm_pit_state ps;
+               struct kvm_memory_alias alias;
+       } u;
 
        switch (ioctl) {
        case KVM_SET_TSS_ADDR:
@@ -1661,17 +1707,14 @@ long kvm_arch_vm_ioctl(struct file *filp,
        case KVM_GET_NR_MMU_PAGES:
                r = kvm_vm_ioctl_get_nr_mmu_pages(kvm);
                break;
-       case KVM_SET_MEMORY_ALIAS: {
-               struct kvm_memory_alias alias;
-
+       case KVM_SET_MEMORY_ALIAS:
                r = -EFAULT;
-               if (copy_from_user(&alias, argp, sizeof alias))
+               if (copy_from_user(&u.alias, argp, sizeof(struct kvm_memory_alias)))
                        goto out;
-               r = kvm_vm_ioctl_set_memory_alias(kvm, &alias);
+               r = kvm_vm_ioctl_set_memory_alias(kvm, &u.alias);
                if (r)
                        goto out;
                break;
-       }
        case KVM_CREATE_IRQCHIP:
                r = -ENOMEM;
                kvm->arch.vpic = kvm_create_pic(kvm);
@@ -1699,13 +1742,7 @@ long kvm_arch_vm_ioctl(struct file *filp,
                        goto out;
                if (irqchip_in_kernel(kvm)) {
                        mutex_lock(&kvm->lock);
-                       if (irq_event.irq < 16)
-                               kvm_pic_set_irq(pic_irqchip(kvm),
-                                       irq_event.irq,
-                                       irq_event.level);
-                       kvm_ioapic_set_irq(kvm->arch.vioapic,
-                                       irq_event.irq,
-                                       irq_event.level);
+                       kvm_set_irq(kvm, irq_event.irq, irq_event.level);
                        mutex_unlock(&kvm->lock);
                        r = 0;
                }
@@ -1713,65 +1750,77 @@ long kvm_arch_vm_ioctl(struct file *filp,
        }
        case KVM_GET_IRQCHIP: {
                /* 0: PIC master, 1: PIC slave, 2: IOAPIC */
-               struct kvm_irqchip chip;
+               struct kvm_irqchip *chip = kmalloc(sizeof(*chip), GFP_KERNEL);
 
-               r = -EFAULT;
-               if (copy_from_user(&chip, argp, sizeof chip))
+               r = -ENOMEM;
+               if (!chip)
                        goto out;
+               r = -EFAULT;
+               if (copy_from_user(chip, argp, sizeof *chip))
+                       goto get_irqchip_out;
                r = -ENXIO;
                if (!irqchip_in_kernel(kvm))
-                       goto out;
-               r = kvm_vm_ioctl_get_irqchip(kvm, &chip);
+                       goto get_irqchip_out;
+               r = kvm_vm_ioctl_get_irqchip(kvm, chip);
                if (r)
-                       goto out;
+                       goto get_irqchip_out;
                r = -EFAULT;
-               if (copy_to_user(argp, &chip, sizeof chip))
-                       goto out;
+               if (copy_to_user(argp, chip, sizeof *chip))
+                       goto get_irqchip_out;
                r = 0;
+       get_irqchip_out:
+               kfree(chip);
+               if (r)
+                       goto out;
                break;
        }
        case KVM_SET_IRQCHIP: {
                /* 0: PIC master, 1: PIC slave, 2: IOAPIC */
-               struct kvm_irqchip chip;
+               struct kvm_irqchip *chip = kmalloc(sizeof(*chip), GFP_KERNEL);
 
-               r = -EFAULT;
-               if (copy_from_user(&chip, argp, sizeof chip))
+               r = -ENOMEM;
+               if (!chip)
                        goto out;
+               r = -EFAULT;
+               if (copy_from_user(chip, argp, sizeof *chip))
+                       goto set_irqchip_out;
                r = -ENXIO;
                if (!irqchip_in_kernel(kvm))
-                       goto out;
-               r = kvm_vm_ioctl_set_irqchip(kvm, &chip);
+                       goto set_irqchip_out;
+               r = kvm_vm_ioctl_set_irqchip(kvm, chip);
                if (r)
-                       goto out;
+                       goto set_irqchip_out;
                r = 0;
+       set_irqchip_out:
+               kfree(chip);
+               if (r)
+                       goto out;
                break;
        }
        case KVM_GET_PIT: {
-               struct kvm_pit_state ps;
                r = -EFAULT;
-               if (copy_from_user(&ps, argp, sizeof ps))
+               if (copy_from_user(&u.ps, argp, sizeof(struct kvm_pit_state)))
                        goto out;
                r = -ENXIO;
                if (!kvm->arch.vpit)
                        goto out;
-               r = kvm_vm_ioctl_get_pit(kvm, &ps);
+               r = kvm_vm_ioctl_get_pit(kvm, &u.ps);
                if (r)
                        goto out;
                r = -EFAULT;
-               if (copy_to_user(argp, &ps, sizeof ps))
+               if (copy_to_user(argp, &u.ps, sizeof(struct kvm_pit_state)))
                        goto out;
                r = 0;
                break;
        }
        case KVM_SET_PIT: {
-               struct kvm_pit_state ps;
                r = -EFAULT;
-               if (copy_from_user(&ps, argp, sizeof ps))
+               if (copy_from_user(&u.ps, argp, sizeof u.ps))
                        goto out;
                r = -ENXIO;
                if (!kvm->arch.vpit)
                        goto out;
-               r = kvm_vm_ioctl_set_pit(kvm, &ps);
+               r = kvm_vm_ioctl_set_pit(kvm, &u.ps);
                if (r)
                        goto out;
                r = 0;
@@ -2018,9 +2067,7 @@ static int emulator_cmpxchg_emulated(unsigned long addr,
 
                val = *(u64 *)new;
 
-               down_read(&current->mm->mmap_sem);
                page = gfn_to_page(vcpu->kvm, gpa >> PAGE_SHIFT);
-               up_read(&current->mm->mmap_sem);
 
                kaddr = kmap_atomic(page, KM_USER0);
                set_64bit((u64 *)(kaddr + offset_in_page(gpa)), val);
@@ -2040,6 +2087,7 @@ static unsigned long get_segment_base(struct kvm_vcpu *vcpu, int seg)
 
 int emulate_invlpg(struct kvm_vcpu *vcpu, gva_t address)
 {
+       kvm_mmu_invlpg(vcpu, address);
        return X86EMUL_CONTINUE;
 }
 
@@ -2080,7 +2128,7 @@ int emulator_set_dr(struct x86_emulate_ctxt *ctxt, int dr, unsigned long value)
 void kvm_report_emulation_failure(struct kvm_vcpu *vcpu, const char *context)
 {
        u8 opcodes[4];
-       unsigned long rip = vcpu->arch.rip;
+       unsigned long rip = kvm_rip_read(vcpu);
        unsigned long rip_linear;
 
        if (!printk_ratelimit())
@@ -2102,6 +2150,14 @@ static struct x86_emulate_ops emulate_ops = {
        .cmpxchg_emulated    = emulator_cmpxchg_emulated,
 };
 
+static void cache_all_regs(struct kvm_vcpu *vcpu)
+{
+       kvm_register_read(vcpu, VCPU_REGS_RAX);
+       kvm_register_read(vcpu, VCPU_REGS_RSP);
+       kvm_register_read(vcpu, VCPU_REGS_RIP);
+       vcpu->arch.regs_dirty = ~0;
+}
+
 int emulate_instruction(struct kvm_vcpu *vcpu,
                        struct kvm_run *run,
                        unsigned long cr2,
@@ -2111,8 +2167,15 @@ int emulate_instruction(struct kvm_vcpu *vcpu,
        int r;
        struct decode_cache *c;
 
+       kvm_clear_exception_queue(vcpu);
        vcpu->arch.mmio_fault_cr2 = cr2;
-       kvm_x86_ops->cache_regs(vcpu);
+       /*
+        * TODO: fix x86_emulate.c to use guest_read/write_register
+        * instead of direct ->regs accesses, can save hundred cycles
+        * on Intel for instructions that don't read/change RSP, for
+        * for example.
+        */
+       cache_all_regs(vcpu);
 
        vcpu->mmio_is_write = 0;
        vcpu->arch.pio.string = 0;
@@ -2172,7 +2235,6 @@ int emulate_instruction(struct kvm_vcpu *vcpu,
                return EMULATE_DO_MMIO;
        }
 
-       kvm_x86_ops->decache_regs(vcpu);
        kvm_x86_ops->set_rflags(vcpu, vcpu->arch.emulate_ctxt.eflags);
 
        if (vcpu->mmio_is_write) {
@@ -2225,20 +2287,19 @@ int complete_pio(struct kvm_vcpu *vcpu)
        struct kvm_pio_request *io = &vcpu->arch.pio;
        long delta;
        int r;
-
-       kvm_x86_ops->cache_regs(vcpu);
+       unsigned long val;
 
        if (!io->string) {
-               if (io->in)
-                       memcpy(&vcpu->arch.regs[VCPU_REGS_RAX], vcpu->arch.pio_data,
-                              io->size);
+               if (io->in) {
+                       val = kvm_register_read(vcpu, VCPU_REGS_RAX);
+                       memcpy(&val, vcpu->arch.pio_data, io->size);
+                       kvm_register_write(vcpu, VCPU_REGS_RAX, val);
+               }
        } else {
                if (io->in) {
                        r = pio_copy_data(vcpu);
-                       if (r) {
-                               kvm_x86_ops->cache_regs(vcpu);
+                       if (r)
                                return r;
-                       }
                }
 
                delta = 1;
@@ -2248,19 +2309,24 @@ int complete_pio(struct kvm_vcpu *vcpu)
                         * The size of the register should really depend on
                         * current address size.
                         */
-                       vcpu->arch.regs[VCPU_REGS_RCX] -= delta;
+                       val = kvm_register_read(vcpu, VCPU_REGS_RCX);
+                       val -= delta;
+                       kvm_register_write(vcpu, VCPU_REGS_RCX, val);
                }
                if (io->down)
                        delta = -delta;
                delta *= io->size;
-               if (io->in)
-                       vcpu->arch.regs[VCPU_REGS_RDI] += delta;
-               else
-                       vcpu->arch.regs[VCPU_REGS_RSI] += delta;
+               if (io->in) {
+                       val = kvm_register_read(vcpu, VCPU_REGS_RDI);
+                       val += delta;
+                       kvm_register_write(vcpu, VCPU_REGS_RDI, val);
+               } else {
+                       val = kvm_register_read(vcpu, VCPU_REGS_RSI);
+                       val += delta;
+                       kvm_register_write(vcpu, VCPU_REGS_RSI, val);
+               }
        }
 
-       kvm_x86_ops->decache_regs(vcpu);
-
        io->count -= io->cur_count;
        io->cur_count = 0;
 
@@ -2313,6 +2379,7 @@ int kvm_emulate_pio(struct kvm_vcpu *vcpu, struct kvm_run *run, int in,
                  int size, unsigned port)
 {
        struct kvm_io_device *pio_dev;
+       unsigned long val;
 
        vcpu->run->exit_reason = KVM_EXIT_IO;
        vcpu->run->io.direction = in ? KVM_EXIT_IO_IN : KVM_EXIT_IO_OUT;
@@ -2333,8 +2400,8 @@ int kvm_emulate_pio(struct kvm_vcpu *vcpu, struct kvm_run *run, int in,
                KVMTRACE_2D(IO_WRITE, vcpu, vcpu->run->io.port, (u32)size,
                            handler);
 
-       kvm_x86_ops->cache_regs(vcpu);
-       memcpy(vcpu->arch.pio_data, &vcpu->arch.regs[VCPU_REGS_RAX], 4);
+       val = kvm_register_read(vcpu, VCPU_REGS_RAX);
+       memcpy(vcpu->arch.pio_data, &val, 4);
 
        kvm_x86_ops->skip_emulated_instruction(vcpu);
 
@@ -2492,11 +2559,6 @@ int kvm_emulate_halt(struct kvm_vcpu *vcpu)
        KVMTRACE_0D(HLT, vcpu, handler);
        if (irqchip_in_kernel(vcpu->kvm)) {
                vcpu->arch.mp_state = KVM_MP_STATE_HALTED;
-               up_read(&vcpu->kvm->slots_lock);
-               kvm_vcpu_block(vcpu);
-               down_read(&vcpu->kvm->slots_lock);
-               if (vcpu->arch.mp_state != KVM_MP_STATE_RUNNABLE)
-                       return -EINTR;
                return 1;
        } else {
                vcpu->run->exit_reason = KVM_EXIT_HLT;
@@ -2519,13 +2581,11 @@ int kvm_emulate_hypercall(struct kvm_vcpu *vcpu)
        unsigned long nr, a0, a1, a2, a3, ret;
        int r = 1;
 
-       kvm_x86_ops->cache_regs(vcpu);
-
-       nr = vcpu->arch.regs[VCPU_REGS_RAX];
-       a0 = vcpu->arch.regs[VCPU_REGS_RBX];
-       a1 = vcpu->arch.regs[VCPU_REGS_RCX];
-       a2 = vcpu->arch.regs[VCPU_REGS_RDX];
-       a3 = vcpu->arch.regs[VCPU_REGS_RSI];
+       nr = kvm_register_read(vcpu, VCPU_REGS_RAX);
+       a0 = kvm_register_read(vcpu, VCPU_REGS_RBX);
+       a1 = kvm_register_read(vcpu, VCPU_REGS_RCX);
+       a2 = kvm_register_read(vcpu, VCPU_REGS_RDX);
+       a3 = kvm_register_read(vcpu, VCPU_REGS_RSI);
 
        KVMTRACE_1D(VMMCALL, vcpu, (u32)nr, handler);
 
@@ -2548,8 +2608,7 @@ int kvm_emulate_hypercall(struct kvm_vcpu *vcpu)
                ret = -KVM_ENOSYS;
                break;
        }
-       vcpu->arch.regs[VCPU_REGS_RAX] = ret;
-       kvm_x86_ops->decache_regs(vcpu);
+       kvm_register_write(vcpu, VCPU_REGS_RAX, ret);
        ++vcpu->stat.hypercalls;
        return r;
 }
@@ -2559,6 +2618,7 @@ int kvm_fix_hypercall(struct kvm_vcpu *vcpu)
 {
        char instruction[3];
        int ret = 0;
+       unsigned long rip = kvm_rip_read(vcpu);
 
 
        /*
@@ -2568,9 +2628,8 @@ int kvm_fix_hypercall(struct kvm_vcpu *vcpu)
         */
        kvm_mmu_zap_all(vcpu->kvm);
 
-       kvm_x86_ops->cache_regs(vcpu);
        kvm_x86_ops->patch_hypercall(vcpu, instruction);
-       if (emulator_write_emulated(vcpu->arch.rip, instruction, 3, vcpu)
+       if (emulator_write_emulated(rip, instruction, 3, vcpu)
            != X86EMUL_CONTINUE)
                ret = -EFAULT;
 
@@ -2700,13 +2759,12 @@ void kvm_emulate_cpuid(struct kvm_vcpu *vcpu)
        u32 function, index;
        struct kvm_cpuid_entry2 *e, *best;
 
-       kvm_x86_ops->cache_regs(vcpu);
-       function = vcpu->arch.regs[VCPU_REGS_RAX];
-       index = vcpu->arch.regs[VCPU_REGS_RCX];
-       vcpu->arch.regs[VCPU_REGS_RAX] = 0;
-       vcpu->arch.regs[VCPU_REGS_RBX] = 0;
-       vcpu->arch.regs[VCPU_REGS_RCX] = 0;
-       vcpu->arch.regs[VCPU_REGS_RDX] = 0;
+       function = kvm_register_read(vcpu, VCPU_REGS_RAX);
+       index = kvm_register_read(vcpu, VCPU_REGS_RCX);
+       kvm_register_write(vcpu, VCPU_REGS_RAX, 0);
+       kvm_register_write(vcpu, VCPU_REGS_RBX, 0);
+       kvm_register_write(vcpu, VCPU_REGS_RCX, 0);
+       kvm_register_write(vcpu, VCPU_REGS_RDX, 0);
        best = NULL;
        for (i = 0; i < vcpu->arch.cpuid_nent; ++i) {
                e = &vcpu->arch.cpuid_entries[i];
@@ -2724,18 +2782,17 @@ void kvm_emulate_cpuid(struct kvm_vcpu *vcpu)
                                best = e;
        }
        if (best) {
-               vcpu->arch.regs[VCPU_REGS_RAX] = best->eax;
-               vcpu->arch.regs[VCPU_REGS_RBX] = best->ebx;
-               vcpu->arch.regs[VCPU_REGS_RCX] = best->ecx;
-               vcpu->arch.regs[VCPU_REGS_RDX] = best->edx;
+               kvm_register_write(vcpu, VCPU_REGS_RAX, best->eax);
+               kvm_register_write(vcpu, VCPU_REGS_RBX, best->ebx);
+               kvm_register_write(vcpu, VCPU_REGS_RCX, best->ecx);
+               kvm_register_write(vcpu, VCPU_REGS_RDX, best->edx);
        }
-       kvm_x86_ops->decache_regs(vcpu);
        kvm_x86_ops->skip_emulated_instruction(vcpu);
        KVMTRACE_5D(CPUID, vcpu, function,
-                   (u32)vcpu->arch.regs[VCPU_REGS_RAX],
-                   (u32)vcpu->arch.regs[VCPU_REGS_RBX],
-                   (u32)vcpu->arch.regs[VCPU_REGS_RCX],
-                   (u32)vcpu->arch.regs[VCPU_REGS_RDX], handler);
+                   (u32)kvm_register_read(vcpu, VCPU_REGS_RAX),
+                   (u32)kvm_register_read(vcpu, VCPU_REGS_RBX),
+                   (u32)kvm_register_read(vcpu, VCPU_REGS_RCX),
+                   (u32)kvm_register_read(vcpu, VCPU_REGS_RDX), handler);
 }
 EXPORT_SYMBOL_GPL(kvm_emulate_cpuid);
 
@@ -2776,9 +2833,7 @@ static void vapic_enter(struct kvm_vcpu *vcpu)
        if (!apic || !apic->vapic_addr)
                return;
 
-       down_read(&current->mm->mmap_sem);
        page = gfn_to_page(vcpu->kvm, apic->vapic_addr >> PAGE_SHIFT);
-       up_read(&current->mm->mmap_sem);
 
        vcpu->arch.apic->vapic_page = page;
 }
@@ -2796,28 +2851,10 @@ static void vapic_exit(struct kvm_vcpu *vcpu)
        up_read(&vcpu->kvm->slots_lock);
 }
 
-static int __vcpu_run(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run)
+static int vcpu_enter_guest(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run)
 {
        int r;
 
-       if (unlikely(vcpu->arch.mp_state == KVM_MP_STATE_SIPI_RECEIVED)) {
-               pr_debug("vcpu %d received sipi with vector # %x\n",
-                      vcpu->vcpu_id, vcpu->arch.sipi_vector);
-               kvm_lapic_reset(vcpu);
-               r = kvm_x86_ops->vcpu_reset(vcpu);
-               if (r)
-                       return r;
-               vcpu->arch.mp_state = KVM_MP_STATE_RUNNABLE;
-       }
-
-       down_read(&vcpu->kvm->slots_lock);
-       vapic_enter(vcpu);
-
-preempted:
-       if (vcpu->guest_debug.enabled)
-               kvm_x86_ops->guest_debug_pre(vcpu);
-
-again:
        if (vcpu->requests)
                if (test_and_clear_bit(KVM_REQ_MMU_RELOAD, &vcpu->requests))
                        kvm_mmu_unload(vcpu);
@@ -2829,6 +2866,8 @@ again:
        if (vcpu->requests) {
                if (test_and_clear_bit(KVM_REQ_MIGRATE_TIMER, &vcpu->requests))
                        __kvm_migrate_timers(vcpu);
+               if (test_and_clear_bit(KVM_REQ_MMU_SYNC, &vcpu->requests))
+                       kvm_mmu_sync_roots(vcpu);
                if (test_and_clear_bit(KVM_REQ_TLB_FLUSH, &vcpu->requests))
                        kvm_x86_ops->tlb_flush(vcpu);
                if (test_and_clear_bit(KVM_REQ_REPORT_TPR_ACCESS,
@@ -2854,21 +2893,15 @@ again:
 
        local_irq_disable();
 
-       if (vcpu->requests || need_resched()) {
+       if (vcpu->requests || need_resched() || signal_pending(current)) {
                local_irq_enable();
                preempt_enable();
                r = 1;
                goto out;
        }
 
-       if (signal_pending(current)) {
-               local_irq_enable();
-               preempt_enable();
-               r = -EINTR;
-               kvm_run->exit_reason = KVM_EXIT_INTR;
-               ++vcpu->stat.signal_exits;
-               goto out;
-       }
+       if (vcpu->guest_debug.enabled)
+               kvm_x86_ops->guest_debug_pre(vcpu);
 
        vcpu->guest_mode = 1;
        /*
@@ -2917,8 +2950,8 @@ again:
         * Profile KVM exit RIPs:
         */
        if (unlikely(prof_on == KVM_PROFILING)) {
-               kvm_x86_ops->cache_regs(vcpu);
-               profile_hit(KVM_PROFILING, (void *)vcpu->arch.rip);
+               unsigned long rip = kvm_rip_read(vcpu);
+               profile_hit(KVM_PROFILING, (void *)rip);
        }
 
        if (vcpu->arch.exception.pending && kvm_x86_ops->exception_injected(vcpu))
@@ -2927,26 +2960,63 @@ again:
        kvm_lapic_sync_from_vapic(vcpu);
 
        r = kvm_x86_ops->handle_exit(kvm_run, vcpu);
+out:
+       return r;
+}
 
-       if (r > 0) {
-               if (dm_request_for_irq_injection(vcpu, kvm_run)) {
-                       r = -EINTR;
-                       kvm_run->exit_reason = KVM_EXIT_INTR;
-                       ++vcpu->stat.request_irq_exits;
-                       goto out;
-               }
-               if (!need_resched())
-                       goto again;
+static int __vcpu_run(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run)
+{
+       int r;
+
+       if (unlikely(vcpu->arch.mp_state == KVM_MP_STATE_SIPI_RECEIVED)) {
+               pr_debug("vcpu %d received sipi with vector # %x\n",
+                        vcpu->vcpu_id, vcpu->arch.sipi_vector);
+               kvm_lapic_reset(vcpu);
+               r = kvm_x86_ops->vcpu_reset(vcpu);
+               if (r)
+                       return r;
+               vcpu->arch.mp_state = KVM_MP_STATE_RUNNABLE;
        }
 
-out:
-       up_read(&vcpu->kvm->slots_lock);
-       if (r > 0) {
-               kvm_resched(vcpu);
-               down_read(&vcpu->kvm->slots_lock);
-               goto preempted;
+       down_read(&vcpu->kvm->slots_lock);
+       vapic_enter(vcpu);
+
+       r = 1;
+       while (r > 0) {
+               if (vcpu->arch.mp_state == KVM_MP_STATE_RUNNABLE)
+                       r = vcpu_enter_guest(vcpu, kvm_run);
+               else {
+                       up_read(&vcpu->kvm->slots_lock);
+                       kvm_vcpu_block(vcpu);
+                       down_read(&vcpu->kvm->slots_lock);
+                       if (test_and_clear_bit(KVM_REQ_UNHALT, &vcpu->requests))
+                               if (vcpu->arch.mp_state == KVM_MP_STATE_HALTED)
+                                       vcpu->arch.mp_state =
+                                                       KVM_MP_STATE_RUNNABLE;
+                       if (vcpu->arch.mp_state != KVM_MP_STATE_RUNNABLE)
+                               r = -EINTR;
+               }
+
+               if (r > 0) {
+                       if (dm_request_for_irq_injection(vcpu, kvm_run)) {
+                               r = -EINTR;
+                               kvm_run->exit_reason = KVM_EXIT_INTR;
+                               ++vcpu->stat.request_irq_exits;
+                       }
+                       if (signal_pending(current)) {
+                               r = -EINTR;
+                               kvm_run->exit_reason = KVM_EXIT_INTR;
+                               ++vcpu->stat.signal_exits;
+                       }
+                       if (need_resched()) {
+                               up_read(&vcpu->kvm->slots_lock);
+                               kvm_resched(vcpu);
+                               down_read(&vcpu->kvm->slots_lock);
+                       }
+               }
        }
 
+       up_read(&vcpu->kvm->slots_lock);
        post_kvm_run_save(vcpu, kvm_run);
 
        vapic_exit(vcpu);
@@ -2966,6 +3036,7 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run)
 
        if (unlikely(vcpu->arch.mp_state == KVM_MP_STATE_UNINITIALIZED)) {
                kvm_vcpu_block(vcpu);
+               clear_bit(KVM_REQ_UNHALT, &vcpu->requests);
                r = -EAGAIN;
                goto out;
        }
@@ -2999,11 +3070,9 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run)
                }
        }
 #endif
-       if (kvm_run->exit_reason == KVM_EXIT_HYPERCALL) {
-               kvm_x86_ops->cache_regs(vcpu);
-               vcpu->arch.regs[VCPU_REGS_RAX] = kvm_run->hypercall.ret;
-               kvm_x86_ops->decache_regs(vcpu);
-       }
+       if (kvm_run->exit_reason == KVM_EXIT_HYPERCALL)
+               kvm_register_write(vcpu, VCPU_REGS_RAX,
+                                    kvm_run->hypercall.ret);
 
        r = __vcpu_run(vcpu, kvm_run);
 
@@ -3019,28 +3088,26 @@ int kvm_arch_vcpu_ioctl_get_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
 {
        vcpu_load(vcpu);
 
-       kvm_x86_ops->cache_regs(vcpu);
-
-       regs->rax = vcpu->arch.regs[VCPU_REGS_RAX];
-       regs->rbx = vcpu->arch.regs[VCPU_REGS_RBX];
-       regs->rcx = vcpu->arch.regs[VCPU_REGS_RCX];
-       regs->rdx = vcpu->arch.regs[VCPU_REGS_RDX];
-       regs->rsi = vcpu->arch.regs[VCPU_REGS_RSI];
-       regs->rdi = vcpu->arch.regs[VCPU_REGS_RDI];
-       regs->rsp = vcpu->arch.regs[VCPU_REGS_RSP];
-       regs->rbp = vcpu->arch.regs[VCPU_REGS_RBP];
+       regs->rax = kvm_register_read(vcpu, VCPU_REGS_RAX);
+       regs->rbx = kvm_register_read(vcpu, VCPU_REGS_RBX);
+       regs->rcx = kvm_register_read(vcpu, VCPU_REGS_RCX);
+       regs->rdx = kvm_register_read(vcpu, VCPU_REGS_RDX);
+       regs->rsi = kvm_register_read(vcpu, VCPU_REGS_RSI);
+       regs->rdi = kvm_register_read(vcpu, VCPU_REGS_RDI);
+       regs->rsp = kvm_register_read(vcpu, VCPU_REGS_RSP);
+       regs->rbp = kvm_register_read(vcpu, VCPU_REGS_RBP);
 #ifdef CONFIG_X86_64
-       regs->r8 = vcpu->arch.regs[VCPU_REGS_R8];
-       regs->r9 = vcpu->arch.regs[VCPU_REGS_R9];
-       regs->r10 = vcpu->arch.regs[VCPU_REGS_R10];
-       regs->r11 = vcpu->arch.regs[VCPU_REGS_R11];
-       regs->r12 = vcpu->arch.regs[VCPU_REGS_R12];
-       regs->r13 = vcpu->arch.regs[VCPU_REGS_R13];
-       regs->r14 = vcpu->arch.regs[VCPU_REGS_R14];
-       regs->r15 = vcpu->arch.regs[VCPU_REGS_R15];
+       regs->r8 = kvm_register_read(vcpu, VCPU_REGS_R8);
+       regs->r9 = kvm_register_read(vcpu, VCPU_REGS_R9);
+       regs->r10 = kvm_register_read(vcpu, VCPU_REGS_R10);
+       regs->r11 = kvm_register_read(vcpu, VCPU_REGS_R11);
+       regs->r12 = kvm_register_read(vcpu, VCPU_REGS_R12);
+       regs->r13 = kvm_register_read(vcpu, VCPU_REGS_R13);
+       regs->r14 = kvm_register_read(vcpu, VCPU_REGS_R14);
+       regs->r15 = kvm_register_read(vcpu, VCPU_REGS_R15);
 #endif
 
-       regs->rip = vcpu->arch.rip;
+       regs->rip = kvm_rip_read(vcpu);
        regs->rflags = kvm_x86_ops->get_rflags(vcpu);
 
        /*
@@ -3058,29 +3125,29 @@ int kvm_arch_vcpu_ioctl_set_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
 {
        vcpu_load(vcpu);
 
-       vcpu->arch.regs[VCPU_REGS_RAX] = regs->rax;
-       vcpu->arch.regs[VCPU_REGS_RBX] = regs->rbx;
-       vcpu->arch.regs[VCPU_REGS_RCX] = regs->rcx;
-       vcpu->arch.regs[VCPU_REGS_RDX] = regs->rdx;
-       vcpu->arch.regs[VCPU_REGS_RSI] = regs->rsi;
-       vcpu->arch.regs[VCPU_REGS_RDI] = regs->rdi;
-       vcpu->arch.regs[VCPU_REGS_RSP] = regs->rsp;
-       vcpu->arch.regs[VCPU_REGS_RBP] = regs->rbp;
+       kvm_register_write(vcpu, VCPU_REGS_RAX, regs->rax);
+       kvm_register_write(vcpu, VCPU_REGS_RBX, regs->rbx);
+       kvm_register_write(vcpu, VCPU_REGS_RCX, regs->rcx);
+       kvm_register_write(vcpu, VCPU_REGS_RDX, regs->rdx);
+       kvm_register_write(vcpu, VCPU_REGS_RSI, regs->rsi);
+       kvm_register_write(vcpu, VCPU_REGS_RDI, regs->rdi);
+       kvm_register_write(vcpu, VCPU_REGS_RSP, regs->rsp);
+       kvm_register_write(vcpu, VCPU_REGS_RBP, regs->rbp);
 #ifdef CONFIG_X86_64
-       vcpu->arch.regs[VCPU_REGS_R8] = regs->r8;
-       vcpu->arch.regs[VCPU_REGS_R9] = regs->r9;
-       vcpu->arch.regs[VCPU_REGS_R10] = regs->r10;
-       vcpu->arch.regs[VCPU_REGS_R11] = regs->r11;
-       vcpu->arch.regs[VCPU_REGS_R12] = regs->r12;
-       vcpu->arch.regs[VCPU_REGS_R13] = regs->r13;
-       vcpu->arch.regs[VCPU_REGS_R14] = regs->r14;
-       vcpu->arch.regs[VCPU_REGS_R15] = regs->r15;
+       kvm_register_write(vcpu, VCPU_REGS_R8, regs->r8);
+       kvm_register_write(vcpu, VCPU_REGS_R9, regs->r9);
+       kvm_register_write(vcpu, VCPU_REGS_R10, regs->r10);
+       kvm_register_write(vcpu, VCPU_REGS_R11, regs->r11);
+       kvm_register_write(vcpu, VCPU_REGS_R12, regs->r12);
+       kvm_register_write(vcpu, VCPU_REGS_R13, regs->r13);
+       kvm_register_write(vcpu, VCPU_REGS_R14, regs->r14);
+       kvm_register_write(vcpu, VCPU_REGS_R15, regs->r15);
+
 #endif
 
-       vcpu->arch.rip = regs->rip;
+       kvm_rip_write(vcpu, regs->rip);
        kvm_x86_ops->set_rflags(vcpu, regs->rflags);
 
-       kvm_x86_ops->decache_regs(vcpu);
 
        vcpu->arch.exception.pending = false;
 
@@ -3294,11 +3361,33 @@ static int load_segment_descriptor_to_kvm_desct(struct kvm_vcpu *vcpu,
        return 0;
 }
 
+static int kvm_load_realmode_segment(struct kvm_vcpu *vcpu, u16 selector, int seg)
+{
+       struct kvm_segment segvar = {
+               .base = selector << 4,
+               .limit = 0xffff,
+               .selector = selector,
+               .type = 3,
+               .present = 1,
+               .dpl = 3,
+               .db = 0,
+               .s = 1,
+               .l = 0,
+               .g = 0,
+               .avl = 0,
+               .unusable = 0,
+       };
+       kvm_x86_ops->set_segment(vcpu, &segvar, seg);
+       return 0;
+}
+
 int kvm_load_segment_descriptor(struct kvm_vcpu *vcpu, u16 selector,
                                int type_bits, int seg)
 {
        struct kvm_segment kvm_seg;
 
+       if (!(vcpu->arch.cr0 & X86_CR0_PE))
+               return kvm_load_realmode_segment(vcpu, selector, seg);
        if (load_segment_descriptor_to_kvm_desct(vcpu, selector, &kvm_seg))
                return 1;
        kvm_seg.type |= type_bits;
@@ -3316,17 +3405,16 @@ static void save_state_to_tss32(struct kvm_vcpu *vcpu,
                                struct tss_segment_32 *tss)
 {
        tss->cr3 = vcpu->arch.cr3;
-       tss->eip = vcpu->arch.rip;
+       tss->eip = kvm_rip_read(vcpu);
        tss->eflags = kvm_x86_ops->get_rflags(vcpu);
-       tss->eax = vcpu->arch.regs[VCPU_REGS_RAX];
-       tss->ecx = vcpu->arch.regs[VCPU_REGS_RCX];
-       tss->edx = vcpu->arch.regs[VCPU_REGS_RDX];
-       tss->ebx = vcpu->arch.regs[VCPU_REGS_RBX];
-       tss->esp = vcpu->arch.regs[VCPU_REGS_RSP];
-       tss->ebp = vcpu->arch.regs[VCPU_REGS_RBP];
-       tss->esi = vcpu->arch.regs[VCPU_REGS_RSI];
-       tss->edi = vcpu->arch.regs[VCPU_REGS_RDI];
-
+       tss->eax = kvm_register_read(vcpu, VCPU_REGS_RAX);
+       tss->ecx = kvm_register_read(vcpu, VCPU_REGS_RCX);
+       tss->edx = kvm_register_read(vcpu, VCPU_REGS_RDX);
+       tss->ebx = kvm_register_read(vcpu, VCPU_REGS_RBX);
+       tss->esp = kvm_register_read(vcpu, VCPU_REGS_RSP);
+       tss->ebp = kvm_register_read(vcpu, VCPU_REGS_RBP);
+       tss->esi = kvm_register_read(vcpu, VCPU_REGS_RSI);
+       tss->edi = kvm_register_read(vcpu, VCPU_REGS_RDI);
        tss->es = get_segment_selector(vcpu, VCPU_SREG_ES);
        tss->cs = get_segment_selector(vcpu, VCPU_SREG_CS);
        tss->ss = get_segment_selector(vcpu, VCPU_SREG_SS);
@@ -3342,17 +3430,17 @@ static int load_state_from_tss32(struct kvm_vcpu *vcpu,
 {
        kvm_set_cr3(vcpu, tss->cr3);
 
-       vcpu->arch.rip = tss->eip;
+       kvm_rip_write(vcpu, tss->eip);
        kvm_x86_ops->set_rflags(vcpu, tss->eflags | 2);
 
-       vcpu->arch.regs[VCPU_REGS_RAX] = tss->eax;
-       vcpu->arch.regs[VCPU_REGS_RCX] = tss->ecx;
-       vcpu->arch.regs[VCPU_REGS_RDX] = tss->edx;
-       vcpu->arch.regs[VCPU_REGS_RBX] = tss->ebx;
-       vcpu->arch.regs[VCPU_REGS_RSP] = tss->esp;
-       vcpu->arch.regs[VCPU_REGS_RBP] = tss->ebp;
-       vcpu->arch.regs[VCPU_REGS_RSI] = tss->esi;
-       vcpu->arch.regs[VCPU_REGS_RDI] = tss->edi;
+       kvm_register_write(vcpu, VCPU_REGS_RAX, tss->eax);
+       kvm_register_write(vcpu, VCPU_REGS_RCX, tss->ecx);
+       kvm_register_write(vcpu, VCPU_REGS_RDX, tss->edx);
+       kvm_register_write(vcpu, VCPU_REGS_RBX, tss->ebx);
+       kvm_register_write(vcpu, VCPU_REGS_RSP, tss->esp);
+       kvm_register_write(vcpu, VCPU_REGS_RBP, tss->ebp);
+       kvm_register_write(vcpu, VCPU_REGS_RSI, tss->esi);
+       kvm_register_write(vcpu, VCPU_REGS_RDI, tss->edi);
 
        if (kvm_load_segment_descriptor(vcpu, tss->ldt_selector, 0, VCPU_SREG_LDTR))
                return 1;
@@ -3380,16 +3468,16 @@ static int load_state_from_tss32(struct kvm_vcpu *vcpu,
 static void save_state_to_tss16(struct kvm_vcpu *vcpu,
                                struct tss_segment_16 *tss)
 {
-       tss->ip = vcpu->arch.rip;
+       tss->ip = kvm_rip_read(vcpu);
        tss->flag = kvm_x86_ops->get_rflags(vcpu);
-       tss->ax = vcpu->arch.regs[VCPU_REGS_RAX];
-       tss->cx = vcpu->arch.regs[VCPU_REGS_RCX];
-       tss->dx = vcpu->arch.regs[VCPU_REGS_RDX];
-       tss->bx = vcpu->arch.regs[VCPU_REGS_RBX];
-       tss->sp = vcpu->arch.regs[VCPU_REGS_RSP];
-       tss->bp = vcpu->arch.regs[VCPU_REGS_RBP];
-       tss->si = vcpu->arch.regs[VCPU_REGS_RSI];
-       tss->di = vcpu->arch.regs[VCPU_REGS_RDI];
+       tss->ax = kvm_register_read(vcpu, VCPU_REGS_RAX);
+       tss->cx = kvm_register_read(vcpu, VCPU_REGS_RCX);
+       tss->dx = kvm_register_read(vcpu, VCPU_REGS_RDX);
+       tss->bx = kvm_register_read(vcpu, VCPU_REGS_RBX);
+       tss->sp = kvm_register_read(vcpu, VCPU_REGS_RSP);
+       tss->bp = kvm_register_read(vcpu, VCPU_REGS_RBP);
+       tss->si = kvm_register_read(vcpu, VCPU_REGS_RSI);
+       tss->di = kvm_register_read(vcpu, VCPU_REGS_RDI);
 
        tss->es = get_segment_selector(vcpu, VCPU_SREG_ES);
        tss->cs = get_segment_selector(vcpu, VCPU_SREG_CS);
@@ -3402,16 +3490,16 @@ static void save_state_to_tss16(struct kvm_vcpu *vcpu,
 static int load_state_from_tss16(struct kvm_vcpu *vcpu,
                                 struct tss_segment_16 *tss)
 {
-       vcpu->arch.rip = tss->ip;
+       kvm_rip_write(vcpu, tss->ip);
        kvm_x86_ops->set_rflags(vcpu, tss->flag | 2);
-       vcpu->arch.regs[VCPU_REGS_RAX] = tss->ax;
-       vcpu->arch.regs[VCPU_REGS_RCX] = tss->cx;
-       vcpu->arch.regs[VCPU_REGS_RDX] = tss->dx;
-       vcpu->arch.regs[VCPU_REGS_RBX] = tss->bx;
-       vcpu->arch.regs[VCPU_REGS_RSP] = tss->sp;
-       vcpu->arch.regs[VCPU_REGS_RBP] = tss->bp;
-       vcpu->arch.regs[VCPU_REGS_RSI] = tss->si;
-       vcpu->arch.regs[VCPU_REGS_RDI] = tss->di;
+       kvm_register_write(vcpu, VCPU_REGS_RAX, tss->ax);
+       kvm_register_write(vcpu, VCPU_REGS_RCX, tss->cx);
+       kvm_register_write(vcpu, VCPU_REGS_RDX, tss->dx);
+       kvm_register_write(vcpu, VCPU_REGS_RBX, tss->bx);
+       kvm_register_write(vcpu, VCPU_REGS_RSP, tss->sp);
+       kvm_register_write(vcpu, VCPU_REGS_RBP, tss->bp);
+       kvm_register_write(vcpu, VCPU_REGS_RSI, tss->si);
+       kvm_register_write(vcpu, VCPU_REGS_RDI, tss->di);
 
        if (kvm_load_segment_descriptor(vcpu, tss->ldt, 0, VCPU_SREG_LDTR))
                return 1;
@@ -3534,7 +3622,6 @@ int kvm_task_switch(struct kvm_vcpu *vcpu, u16 tss_selector, int reason)
        }
 
        kvm_x86_ops->skip_emulated_instruction(vcpu);
-       kvm_x86_ops->cache_regs(vcpu);
 
        if (nseg_desc.type & 8)
                ret = kvm_task_switch_32(vcpu, tss_selector, old_tss_base,
@@ -3559,7 +3646,6 @@ int kvm_task_switch(struct kvm_vcpu *vcpu, u16 tss_selector, int reason)
        tr_seg.type = 11;
        kvm_set_segment(vcpu, &tr_seg, VCPU_SREG_TR);
 out:
-       kvm_x86_ops->decache_regs(vcpu);
        return ret;
 }
 EXPORT_SYMBOL_GPL(kvm_task_switch);
@@ -3622,6 +3708,7 @@ int kvm_arch_vcpu_ioctl_set_sregs(struct kvm_vcpu *vcpu,
                        pr_debug("Set back pending irq %d\n",
                                 pending_vec);
                }
+               kvm_pic_clear_isr_ack(vcpu->kvm);
        }
 
        kvm_set_segment(vcpu, &sregs->cs, VCPU_SREG_CS);
@@ -3634,6 +3721,12 @@ int kvm_arch_vcpu_ioctl_set_sregs(struct kvm_vcpu *vcpu,
        kvm_set_segment(vcpu, &sregs->tr, VCPU_SREG_TR);
        kvm_set_segment(vcpu, &sregs->ldt, VCPU_SREG_LDTR);
 
+       /* Older userspace won't unhalt the vcpu on reset. */
+       if (vcpu->vcpu_id == 0 && kvm_rip_read(vcpu) == 0xfff0 &&
+           sregs->cs.selector == 0xf000 && sregs->cs.base == 0xffff0000 &&
+           !(vcpu->arch.cr0 & X86_CR0_PE))
+               vcpu->arch.mp_state = KVM_MP_STATE_RUNNABLE;
+
        vcpu_put(vcpu);
 
        return 0;
@@ -3918,6 +4011,7 @@ struct  kvm *kvm_arch_create_vm(void)
                return ERR_PTR(-ENOMEM);
 
        INIT_LIST_HEAD(&kvm->arch.active_mmu_pages);
+       INIT_LIST_HEAD(&kvm->arch.assigned_dev_head);
 
        return kvm;
 }
@@ -3950,6 +4044,8 @@ static void kvm_free_vcpus(struct kvm *kvm)
 
 void kvm_arch_destroy_vm(struct kvm *kvm)
 {
+       kvm_iommu_unmap_guest(kvm);
+       kvm_free_all_assigned_devices(kvm);
        kvm_free_pit(kvm);
        kfree(kvm->arch.vpic);
        kfree(kvm->arch.vioapic);
@@ -3981,7 +4077,7 @@ int kvm_arch_set_memory_region(struct kvm *kvm,
                        userspace_addr = do_mmap(NULL, 0,
                                                 npages * PAGE_SIZE,
                                                 PROT_READ | PROT_WRITE,
-                                                MAP_SHARED | MAP_ANONYMOUS,
+                                                MAP_PRIVATE | MAP_ANONYMOUS,
                                                 0);
                        up_write(&current->mm->mmap_sem);