KVM: use SRCU for dirty log
[safe/jmp/linux-2.6] / arch / x86 / kvm / x86.c
index 098e7f8..e748835 100644 (file)
 #include <linux/iommu.h>
 #include <linux/intel-iommu.h>
 #include <linux/cpufreq.h>
+#include <linux/user-return-notifier.h>
 #include <trace/events/kvm.h>
 #undef TRACE_INCLUDE_FILE
 #define CREATE_TRACE_POINTS
 #include "trace.h"
 
+#include <asm/debugreg.h>
 #include <asm/uaccess.h>
 #include <asm/msr.h>
 #include <asm/desc.h>
@@ -87,6 +89,25 @@ EXPORT_SYMBOL_GPL(kvm_x86_ops);
 int ignore_msrs = 0;
 module_param_named(ignore_msrs, ignore_msrs, bool, S_IRUGO | S_IWUSR);
 
+#define KVM_NR_SHARED_MSRS 16
+
+struct kvm_shared_msrs_global {
+       int nr;
+       u32 msrs[KVM_NR_SHARED_MSRS];
+};
+
+struct kvm_shared_msrs {
+       struct user_return_notifier urn;
+       bool registered;
+       struct kvm_shared_msr_values {
+               u64 host;
+               u64 curr;
+       } values[KVM_NR_SHARED_MSRS];
+};
+
+static struct kvm_shared_msrs_global __read_mostly shared_msrs_global;
+static DEFINE_PER_CPU(struct kvm_shared_msrs, shared_msrs);
+
 struct kvm_stats_debugfs_item debugfs_entries[] = {
        { "pf_fixed", VCPU_STAT(pf_fixed) },
        { "pf_guest", VCPU_STAT(pf_guest) },
@@ -123,6 +144,83 @@ struct kvm_stats_debugfs_item debugfs_entries[] = {
        { NULL }
 };
 
+static void kvm_on_user_return(struct user_return_notifier *urn)
+{
+       unsigned slot;
+       struct kvm_shared_msrs *locals
+               = container_of(urn, struct kvm_shared_msrs, urn);
+       struct kvm_shared_msr_values *values;
+
+       for (slot = 0; slot < shared_msrs_global.nr; ++slot) {
+               values = &locals->values[slot];
+               if (values->host != values->curr) {
+                       wrmsrl(shared_msrs_global.msrs[slot], values->host);
+                       values->curr = values->host;
+               }
+       }
+       locals->registered = false;
+       user_return_notifier_unregister(urn);
+}
+
+static void shared_msr_update(unsigned slot, u32 msr)
+{
+       struct kvm_shared_msrs *smsr;
+       u64 value;
+
+       smsr = &__get_cpu_var(shared_msrs);
+       /* only read, and nobody should modify it at this time,
+        * so don't need lock */
+       if (slot >= shared_msrs_global.nr) {
+               printk(KERN_ERR "kvm: invalid MSR slot!");
+               return;
+       }
+       rdmsrl_safe(msr, &value);
+       smsr->values[slot].host = value;
+       smsr->values[slot].curr = value;
+}
+
+void kvm_define_shared_msr(unsigned slot, u32 msr)
+{
+       if (slot >= shared_msrs_global.nr)
+               shared_msrs_global.nr = slot + 1;
+       shared_msrs_global.msrs[slot] = msr;
+       /* we need ensured the shared_msr_global have been updated */
+       smp_wmb();
+}
+EXPORT_SYMBOL_GPL(kvm_define_shared_msr);
+
+static void kvm_shared_msr_cpu_online(void)
+{
+       unsigned i;
+
+       for (i = 0; i < shared_msrs_global.nr; ++i)
+               shared_msr_update(i, shared_msrs_global.msrs[i]);
+}
+
+void kvm_set_shared_msr(unsigned slot, u64 value, u64 mask)
+{
+       struct kvm_shared_msrs *smsr = &__get_cpu_var(shared_msrs);
+
+       if (((value ^ smsr->values[slot].curr) & mask) == 0)
+               return;
+       smsr->values[slot].curr = value;
+       wrmsrl(shared_msrs_global.msrs[slot], value);
+       if (!smsr->registered) {
+               smsr->urn.on_user_return = kvm_on_user_return;
+               user_return_notifier_register(&smsr->urn);
+               smsr->registered = true;
+       }
+}
+EXPORT_SYMBOL_GPL(kvm_set_shared_msr);
+
+static void drop_user_return_notifiers(void *ignore)
+{
+       struct kvm_shared_msrs *smsr = &__get_cpu_var(shared_msrs);
+
+       if (smsr->registered)
+               kvm_on_user_return(&smsr->urn);
+}
+
 unsigned long segment_base(u16 selector)
 {
        struct descriptor_table gdt;
@@ -170,12 +268,68 @@ void kvm_set_apic_base(struct kvm_vcpu *vcpu, u64 data)
 }
 EXPORT_SYMBOL_GPL(kvm_set_apic_base);
 
+#define EXCPT_BENIGN           0
+#define EXCPT_CONTRIBUTORY     1
+#define EXCPT_PF               2
+
+static int exception_class(int vector)
+{
+       switch (vector) {
+       case PF_VECTOR:
+               return EXCPT_PF;
+       case DE_VECTOR:
+       case TS_VECTOR:
+       case NP_VECTOR:
+       case SS_VECTOR:
+       case GP_VECTOR:
+               return EXCPT_CONTRIBUTORY;
+       default:
+               break;
+       }
+       return EXCPT_BENIGN;
+}
+
+static void kvm_multiple_exception(struct kvm_vcpu *vcpu,
+               unsigned nr, bool has_error, u32 error_code)
+{
+       u32 prev_nr;
+       int class1, class2;
+
+       if (!vcpu->arch.exception.pending) {
+       queue:
+               vcpu->arch.exception.pending = true;
+               vcpu->arch.exception.has_error_code = has_error;
+               vcpu->arch.exception.nr = nr;
+               vcpu->arch.exception.error_code = error_code;
+               return;
+       }
+
+       /* to check exception */
+       prev_nr = vcpu->arch.exception.nr;
+       if (prev_nr == DF_VECTOR) {
+               /* triple fault -> shutdown */
+               set_bit(KVM_REQ_TRIPLE_FAULT, &vcpu->requests);
+               return;
+       }
+       class1 = exception_class(prev_nr);
+       class2 = exception_class(nr);
+       if ((class1 == EXCPT_CONTRIBUTORY && class2 == EXCPT_CONTRIBUTORY)
+               || (class1 == EXCPT_PF && class2 != EXCPT_BENIGN)) {
+               /* generate double fault per SDM Table 5-5 */
+               vcpu->arch.exception.pending = true;
+               vcpu->arch.exception.has_error_code = true;
+               vcpu->arch.exception.nr = DF_VECTOR;
+               vcpu->arch.exception.error_code = 0;
+       } else
+               /* replace previous exception with a new one in a hope
+                  that instruction re-execution will regenerate lost
+                  exception */
+               goto queue;
+}
+
 void kvm_queue_exception(struct kvm_vcpu *vcpu, unsigned nr)
 {
-       WARN_ON(vcpu->arch.exception.pending);
-       vcpu->arch.exception.pending = true;
-       vcpu->arch.exception.has_error_code = false;
-       vcpu->arch.exception.nr = nr;
+       kvm_multiple_exception(vcpu, nr, false, 0);
 }
 EXPORT_SYMBOL_GPL(kvm_queue_exception);
 
@@ -183,25 +337,6 @@ void kvm_inject_page_fault(struct kvm_vcpu *vcpu, unsigned long addr,
                           u32 error_code)
 {
        ++vcpu->stat.pf_guest;
-
-       if (vcpu->arch.exception.pending) {
-               switch(vcpu->arch.exception.nr) {
-               case DF_VECTOR:
-                       /* triple fault -> shutdown */
-                       set_bit(KVM_REQ_TRIPLE_FAULT, &vcpu->requests);
-                       return;
-               case PF_VECTOR:
-                       vcpu->arch.exception.nr = DF_VECTOR;
-                       vcpu->arch.exception.error_code = 0;
-                       return;
-               default:
-                       /* replace previous exception with a new one in a hope
-                          that instruction re-execution will regenerate lost
-                          exception */
-                       vcpu->arch.exception.pending = false;
-                       break;
-               }
-       }
        vcpu->arch.cr2 = addr;
        kvm_queue_exception_e(vcpu, PF_VECTOR, error_code);
 }
@@ -214,11 +349,7 @@ EXPORT_SYMBOL_GPL(kvm_inject_nmi);
 
 void kvm_queue_exception_e(struct kvm_vcpu *vcpu, unsigned nr, u32 error_code)
 {
-       WARN_ON(vcpu->arch.exception.pending);
-       vcpu->arch.exception.pending = true;
-       vcpu->arch.exception.has_error_code = true;
-       vcpu->arch.exception.nr = nr;
-       vcpu->arch.exception.error_code = error_code;
+       kvm_multiple_exception(vcpu, nr, true, error_code);
 }
 EXPORT_SYMBOL_GPL(kvm_queue_exception_e);
 
@@ -235,25 +366,6 @@ bool kvm_require_cpl(struct kvm_vcpu *vcpu, int required_cpl)
 }
 EXPORT_SYMBOL_GPL(kvm_require_cpl);
 
-unsigned long kvm_get_rflags(struct kvm_vcpu *vcpu)
-{
-       unsigned long rflags;
-
-       rflags = kvm_x86_ops->get_rflags(vcpu);
-       if (vcpu->guest_debug & KVM_GUESTDBG_SINGLESTEP)
-               rflags &= ~(unsigned long)(X86_EFLAGS_TF | X86_EFLAGS_RF);
-       return rflags;
-}
-EXPORT_SYMBOL_GPL(kvm_get_rflags);
-
-void kvm_set_rflags(struct kvm_vcpu *vcpu, unsigned long rflags)
-{
-       if (vcpu->guest_debug & KVM_GUESTDBG_SINGLESTEP)
-               rflags |= X86_EFLAGS_TF | X86_EFLAGS_RF;
-       kvm_x86_ops->set_rflags(vcpu, rflags);
-}
-EXPORT_SYMBOL_GPL(kvm_set_rflags);
-
 /*
  * Load the pae pdptrs.  Return true is they are all valid.
  */
@@ -381,7 +493,7 @@ EXPORT_SYMBOL_GPL(kvm_lmsw);
 
 void kvm_set_cr4(struct kvm_vcpu *vcpu, unsigned long cr4)
 {
-       unsigned long old_cr4 = vcpu->arch.cr4;
+       unsigned long old_cr4 = kvm_read_cr4(vcpu);
        unsigned long pdptr_bits = X86_CR4_PGE | X86_CR4_PSE | X86_CR4_PAE;
 
        if (cr4 & CR4_RESERVED_BITS) {
@@ -602,7 +714,7 @@ static void kvm_write_wall_clock(struct kvm *kvm, gpa_t wall_clock)
 {
        static int version;
        struct pvclock_wall_clock wc;
-       struct timespec now, sys, boot;
+       struct timespec boot;
 
        if (!wall_clock)
                return;
@@ -617,9 +729,7 @@ static void kvm_write_wall_clock(struct kvm *kvm, gpa_t wall_clock)
         * wall clock specified here.  guest system time equals host
         * system time for us, thus we must fill in host boot time here.
         */
-       now = current_kernel_time();
-       ktime_get_ts(&sys);
-       boot = ns_to_timespec(timespec_to_ns(&now) - timespec_to_ns(&sys));
+       getboottime(&boot);
 
        wc.sec = boot.tv_sec;
        wc.nsec = boot.tv_nsec;
@@ -694,12 +804,14 @@ static void kvm_write_guest_time(struct kvm_vcpu *v)
        local_irq_save(flags);
        kvm_get_msr(v, MSR_IA32_TSC, &vcpu->hv_clock.tsc_timestamp);
        ktime_get_ts(&ts);
+       monotonic_to_bootbased(&ts);
        local_irq_restore(flags);
 
        /* With all the info we got, fill in the values */
 
        vcpu->hv_clock.system_time = ts.tv_nsec +
-                                    (NSEC_PER_SEC * (u64)ts.tv_sec);
+                                    (NSEC_PER_SEC * (u64)ts.tv_sec) + v->kvm->arch.kvmclock_offset;
+
        /*
         * The interface expects us to write an even number signaling that the
         * update is finished. Since the guest won't see the intermediate
@@ -857,6 +969,38 @@ static int set_msr_mce(struct kvm_vcpu *vcpu, u32 msr, u64 data)
        return 0;
 }
 
+static int xen_hvm_config(struct kvm_vcpu *vcpu, u64 data)
+{
+       struct kvm *kvm = vcpu->kvm;
+       int lm = is_long_mode(vcpu);
+       u8 *blob_addr = lm ? (u8 *)(long)kvm->arch.xen_hvm_config.blob_addr_64
+               : (u8 *)(long)kvm->arch.xen_hvm_config.blob_addr_32;
+       u8 blob_size = lm ? kvm->arch.xen_hvm_config.blob_size_64
+               : kvm->arch.xen_hvm_config.blob_size_32;
+       u32 page_num = data & ~PAGE_MASK;
+       u64 page_addr = data & PAGE_MASK;
+       u8 *page;
+       int r;
+
+       r = -E2BIG;
+       if (page_num >= blob_size)
+               goto out;
+       r = -ENOMEM;
+       page = kzalloc(PAGE_SIZE, GFP_KERNEL);
+       if (!page)
+               goto out;
+       r = -EFAULT;
+       if (copy_from_user(page, blob_addr + (page_num * PAGE_SIZE), PAGE_SIZE))
+               goto out_free;
+       if (kvm_write_guest(kvm, page_addr, page, PAGE_SIZE))
+               goto out_free;
+       r = 0;
+out_free:
+       kfree(page);
+out:
+       return r;
+}
+
 int kvm_set_msr_common(struct kvm_vcpu *vcpu, u32 msr, u64 data)
 {
        switch (msr) {
@@ -972,6 +1116,8 @@ int kvm_set_msr_common(struct kvm_vcpu *vcpu, u32 msr, u64 data)
                        "0x%x data 0x%llx\n", msr, data);
                break;
        default:
+               if (msr && (msr == vcpu->kvm->arch.xen_hvm_config.msr))
+                       return xen_hvm_config(vcpu, data);
                if (!ignore_msrs) {
                        pr_unimpl(vcpu, "unhandled wrmsr: 0x%x data %llx\n",
                                msr, data);
@@ -1246,6 +1392,9 @@ int kvm_dev_ioctl_check_extension(long ext)
        case KVM_CAP_PIT2:
        case KVM_CAP_PIT_STATE2:
        case KVM_CAP_SET_IDENTITY_MAP_ADDR:
+       case KVM_CAP_XEN_HVM:
+       case KVM_CAP_ADJUST_CLOCK:
+       case KVM_CAP_VCPU_EVENTS:
                r = 1;
                break;
        case KVM_CAP_COALESCED_MMIO:
@@ -1348,8 +1497,12 @@ out:
 void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
 {
        kvm_x86_ops->vcpu_load(vcpu, cpu);
-       if (unlikely(per_cpu(cpu_tsc_khz, cpu) == 0))
-               per_cpu(cpu_tsc_khz, cpu) = cpufreq_quick_get(cpu);
+       if (unlikely(per_cpu(cpu_tsc_khz, cpu) == 0)) {
+               unsigned long khz = cpufreq_quick_get(cpu);
+               if (!khz)
+                       khz = tsc_khz;
+               per_cpu(cpu_tsc_khz, cpu) = khz;
+       }
        kvm_request_guest_time_update(vcpu);
 }
 
@@ -1421,6 +1574,7 @@ static int kvm_vcpu_ioctl_set_cpuid(struct kvm_vcpu *vcpu,
        cpuid_fix_nx_cap(vcpu);
        r = 0;
        kvm_apic_set_version(vcpu);
+       kvm_x86_ops->cpuid_update(vcpu);
 
 out_free:
        vfree(cpuid_entries);
@@ -1443,6 +1597,7 @@ static int kvm_vcpu_ioctl_set_cpuid2(struct kvm_vcpu *vcpu,
                goto out;
        vcpu->arch.cpuid_nent = cpuid->nent;
        kvm_apic_set_version(vcpu);
+       kvm_x86_ops->cpuid_update(vcpu);
        return 0;
 
 out:
@@ -1491,6 +1646,7 @@ static void do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 function,
 #else
        unsigned f_lm = 0;
 #endif
+       unsigned f_rdtscp = kvm_x86_ops->rdtscp_supported() ? F(RDTSCP) : 0;
 
        /* cpuid 1.edx */
        const u32 kvm_supported_word0_x86_features =
@@ -1510,7 +1666,7 @@ static void do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 function,
                F(MTRR) | F(PGE) | F(MCA) | F(CMOV) |
                F(PAT) | F(PSE36) | 0 /* Reserved */ |
                f_nx | 0 /* Reserved */ | F(MMXEXT) | F(MMX) |
-               F(FXSR) | F(FXSR_OPT) | f_gbpages | 0 /* RDTSCP */ |
+               F(FXSR) | F(FXSR_OPT) | f_gbpages | f_rdtscp |
                0 /* Reserved */ | f_lm | F(3DNOWEXT) | F(3DNOW);
        /* cpuid 1.ecx */
        const u32 kvm_supported_word4_x86_features =
@@ -1757,7 +1913,7 @@ static int kvm_vcpu_ioctl_x86_set_mce(struct kvm_vcpu *vcpu,
                return 0;
        if (mce->status & MCI_STATUS_UC) {
                if ((vcpu->arch.mcg_status & MCG_STATUS_MCIP) ||
-                   !(vcpu->arch.cr4 & X86_CR4_MCE)) {
+                   !kvm_read_cr4_bits(vcpu, X86_CR4_MCE)) {
                        printk(KERN_DEBUG "kvm: set_mce: "
                               "injects mce exception while "
                               "previous one is in progress!\n");
@@ -1783,6 +1939,65 @@ static int kvm_vcpu_ioctl_x86_set_mce(struct kvm_vcpu *vcpu,
        return 0;
 }
 
+static void kvm_vcpu_ioctl_x86_get_vcpu_events(struct kvm_vcpu *vcpu,
+                                              struct kvm_vcpu_events *events)
+{
+       vcpu_load(vcpu);
+
+       events->exception.injected = vcpu->arch.exception.pending;
+       events->exception.nr = vcpu->arch.exception.nr;
+       events->exception.has_error_code = vcpu->arch.exception.has_error_code;
+       events->exception.error_code = vcpu->arch.exception.error_code;
+
+       events->interrupt.injected = vcpu->arch.interrupt.pending;
+       events->interrupt.nr = vcpu->arch.interrupt.nr;
+       events->interrupt.soft = vcpu->arch.interrupt.soft;
+
+       events->nmi.injected = vcpu->arch.nmi_injected;
+       events->nmi.pending = vcpu->arch.nmi_pending;
+       events->nmi.masked = kvm_x86_ops->get_nmi_mask(vcpu);
+
+       events->sipi_vector = vcpu->arch.sipi_vector;
+
+       events->flags = (KVM_VCPUEVENT_VALID_NMI_PENDING
+                        | KVM_VCPUEVENT_VALID_SIPI_VECTOR);
+
+       vcpu_put(vcpu);
+}
+
+static int kvm_vcpu_ioctl_x86_set_vcpu_events(struct kvm_vcpu *vcpu,
+                                             struct kvm_vcpu_events *events)
+{
+       if (events->flags & ~(KVM_VCPUEVENT_VALID_NMI_PENDING
+                             | KVM_VCPUEVENT_VALID_SIPI_VECTOR))
+               return -EINVAL;
+
+       vcpu_load(vcpu);
+
+       vcpu->arch.exception.pending = events->exception.injected;
+       vcpu->arch.exception.nr = events->exception.nr;
+       vcpu->arch.exception.has_error_code = events->exception.has_error_code;
+       vcpu->arch.exception.error_code = events->exception.error_code;
+
+       vcpu->arch.interrupt.pending = events->interrupt.injected;
+       vcpu->arch.interrupt.nr = events->interrupt.nr;
+       vcpu->arch.interrupt.soft = events->interrupt.soft;
+       if (vcpu->arch.interrupt.pending && irqchip_in_kernel(vcpu->kvm))
+               kvm_pic_clear_isr_ack(vcpu->kvm);
+
+       vcpu->arch.nmi_injected = events->nmi.injected;
+       if (events->flags & KVM_VCPUEVENT_VALID_NMI_PENDING)
+               vcpu->arch.nmi_pending = events->nmi.pending;
+       kvm_x86_ops->set_nmi_mask(vcpu, events->nmi.masked);
+
+       if (events->flags & KVM_VCPUEVENT_VALID_SIPI_VECTOR)
+               vcpu->arch.sipi_vector = events->sipi_vector;
+
+       vcpu_put(vcpu);
+
+       return 0;
+}
+
 long kvm_arch_vcpu_ioctl(struct file *filp,
                         unsigned int ioctl, unsigned long arg)
 {
@@ -1793,6 +2008,9 @@ long kvm_arch_vcpu_ioctl(struct file *filp,
 
        switch (ioctl) {
        case KVM_GET_LAPIC: {
+               r = -EINVAL;
+               if (!vcpu->arch.apic)
+                       goto out;
                lapic = kzalloc(sizeof(struct kvm_lapic_state), GFP_KERNEL);
 
                r = -ENOMEM;
@@ -1808,6 +2026,9 @@ long kvm_arch_vcpu_ioctl(struct file *filp,
                break;
        }
        case KVM_SET_LAPIC: {
+               r = -EINVAL;
+               if (!vcpu->arch.apic)
+                       goto out;
                lapic = kmalloc(sizeof(struct kvm_lapic_state), GFP_KERNEL);
                r = -ENOMEM;
                if (!lapic)
@@ -1934,6 +2155,27 @@ long kvm_arch_vcpu_ioctl(struct file *filp,
                r = kvm_vcpu_ioctl_x86_set_mce(vcpu, &mce);
                break;
        }
+       case KVM_GET_VCPU_EVENTS: {
+               struct kvm_vcpu_events events;
+
+               kvm_vcpu_ioctl_x86_get_vcpu_events(vcpu, &events);
+
+               r = -EFAULT;
+               if (copy_to_user(argp, &events, sizeof(struct kvm_vcpu_events)))
+                       break;
+               r = 0;
+               break;
+       }
+       case KVM_SET_VCPU_EVENTS: {
+               struct kvm_vcpu_events events;
+
+               r = -EFAULT;
+               if (copy_from_user(&events, argp, sizeof(struct kvm_vcpu_events)))
+                       break;
+
+               r = kvm_vcpu_ioctl_x86_set_vcpu_events(vcpu, &events);
+               break;
+       }
        default:
                r = -EINVAL;
        }
@@ -1985,9 +2227,10 @@ gfn_t unalias_gfn(struct kvm *kvm, gfn_t gfn)
 {
        int i;
        struct kvm_mem_alias *alias;
+       struct kvm_mem_aliases *aliases = kvm->arch.aliases;
 
-       for (i = 0; i < kvm->arch.naliases; ++i) {
-               alias = &kvm->arch.aliases[i];
+       for (i = 0; i < aliases->naliases; ++i) {
+               alias = &aliases->aliases[i];
                if (gfn >= alias->base_gfn
                    && gfn < alias->base_gfn + alias->npages)
                        return alias->target_gfn + gfn - alias->base_gfn;
@@ -2005,6 +2248,7 @@ static int kvm_vm_ioctl_set_memory_alias(struct kvm *kvm,
 {
        int r, n;
        struct kvm_mem_alias *p;
+       struct kvm_mem_aliases *aliases;
 
        r = -EINVAL;
        /* General sanity checks */
@@ -2024,15 +2268,17 @@ static int kvm_vm_ioctl_set_memory_alias(struct kvm *kvm,
        down_write(&kvm->slots_lock);
        spin_lock(&kvm->mmu_lock);
 
-       p = &kvm->arch.aliases[alias->slot];
+       aliases = kvm->arch.aliases;
+
+       p = &aliases->aliases[alias->slot];
        p->base_gfn = alias->guest_phys_addr >> PAGE_SHIFT;
        p->npages = alias->memory_size >> PAGE_SHIFT;
        p->target_gfn = alias->target_phys_addr >> PAGE_SHIFT;
 
        for (n = KVM_ALIAS_SLOTS; n > 0; --n)
-               if (kvm->arch.aliases[n - 1].npages)
+               if (aliases->aliases[n - 1].npages)
                        break;
-       kvm->arch.naliases = n;
+       aliases->naliases = n;
 
        spin_unlock(&kvm->mmu_lock);
        kvm_mmu_zap_all(kvm);
@@ -2169,27 +2415,60 @@ static int kvm_vm_ioctl_reinject(struct kvm *kvm,
 int kvm_vm_ioctl_get_dirty_log(struct kvm *kvm,
                                      struct kvm_dirty_log *log)
 {
-       int r;
-       int n;
+       int r, n, i;
        struct kvm_memory_slot *memslot;
-       int is_dirty = 0;
+       unsigned long is_dirty = 0;
+       unsigned long *dirty_bitmap = NULL;
 
        down_write(&kvm->slots_lock);
 
-       r = kvm_get_dirty_log(kvm, log, &is_dirty);
-       if (r)
+       r = -EINVAL;
+       if (log->slot >= KVM_MEMORY_SLOTS)
+               goto out;
+
+       memslot = &kvm->memslots->memslots[log->slot];
+       r = -ENOENT;
+       if (!memslot->dirty_bitmap)
+               goto out;
+
+       n = ALIGN(memslot->npages, BITS_PER_LONG) / 8;
+
+       r = -ENOMEM;
+       dirty_bitmap = vmalloc(n);
+       if (!dirty_bitmap)
                goto out;
+       memset(dirty_bitmap, 0, n);
+
+       for (i = 0; !is_dirty && i < n/sizeof(long); i++)
+               is_dirty = memslot->dirty_bitmap[i];
 
        /* If nothing is dirty, don't bother messing with page tables. */
        if (is_dirty) {
+               struct kvm_memslots *slots, *old_slots;
+
                spin_lock(&kvm->mmu_lock);
                kvm_mmu_slot_remove_write_access(kvm, log->slot);
                spin_unlock(&kvm->mmu_lock);
-               memslot = &kvm->memslots[log->slot];
-               n = ALIGN(memslot->npages, BITS_PER_LONG) / 8;
-               memset(memslot->dirty_bitmap, 0, n);
+
+               slots = kzalloc(sizeof(struct kvm_memslots), GFP_KERNEL);
+               if (!slots)
+                       goto out_free;
+
+               memcpy(slots, kvm->memslots, sizeof(struct kvm_memslots));
+               slots->memslots[log->slot].dirty_bitmap = dirty_bitmap;
+
+               old_slots = kvm->memslots;
+               rcu_assign_pointer(kvm->memslots, slots);
+               synchronize_srcu_expedited(&kvm->srcu);
+               dirty_bitmap = old_slots->memslots[log->slot].dirty_bitmap;
+               kfree(old_slots);
        }
+
        r = 0;
+       if (copy_to_user(log->dirty_bitmap, dirty_bitmap, n))
+               r = -EFAULT;
+out_free:
+       vfree(dirty_bitmap);
 out:
        up_write(&kvm->slots_lock);
        return r;
@@ -2262,25 +2541,39 @@ long kvm_arch_vm_ioctl(struct file *filp,
                if (r)
                        goto out;
                break;
-       case KVM_CREATE_IRQCHIP:
+       case KVM_CREATE_IRQCHIP: {
+               struct kvm_pic *vpic;
+
+               mutex_lock(&kvm->lock);
+               r = -EEXIST;
+               if (kvm->arch.vpic)
+                       goto create_irqchip_unlock;
                r = -ENOMEM;
-               kvm->arch.vpic = kvm_create_pic(kvm);
-               if (kvm->arch.vpic) {
+               vpic = kvm_create_pic(kvm);
+               if (vpic) {
                        r = kvm_ioapic_init(kvm);
                        if (r) {
-                               kfree(kvm->arch.vpic);
-                               kvm->arch.vpic = NULL;
-                               goto out;
+                               kfree(vpic);
+                               goto create_irqchip_unlock;
                        }
                } else
-                       goto out;
+                       goto create_irqchip_unlock;
+               smp_wmb();
+               kvm->arch.vpic = vpic;
+               smp_wmb();
                r = kvm_setup_default_irq_routing(kvm);
                if (r) {
+                       mutex_lock(&kvm->irq_lock);
                        kfree(kvm->arch.vpic);
                        kfree(kvm->arch.vioapic);
-                       goto out;
+                       kvm->arch.vpic = NULL;
+                       kvm->arch.vioapic = NULL;
+                       mutex_unlock(&kvm->irq_lock);
                }
+       create_irqchip_unlock:
+               mutex_unlock(&kvm->lock);
                break;
+       }
        case KVM_CREATE_PIT:
                u.pit_config.flags = KVM_PIT_SPEAKER_DUMMY;
                goto create_pit;
@@ -2437,6 +2730,55 @@ long kvm_arch_vm_ioctl(struct file *filp,
                r = 0;
                break;
        }
+       case KVM_XEN_HVM_CONFIG: {
+               r = -EFAULT;
+               if (copy_from_user(&kvm->arch.xen_hvm_config, argp,
+                                  sizeof(struct kvm_xen_hvm_config)))
+                       goto out;
+               r = -EINVAL;
+               if (kvm->arch.xen_hvm_config.flags)
+                       goto out;
+               r = 0;
+               break;
+       }
+       case KVM_SET_CLOCK: {
+               struct timespec now;
+               struct kvm_clock_data user_ns;
+               u64 now_ns;
+               s64 delta;
+
+               r = -EFAULT;
+               if (copy_from_user(&user_ns, argp, sizeof(user_ns)))
+                       goto out;
+
+               r = -EINVAL;
+               if (user_ns.flags)
+                       goto out;
+
+               r = 0;
+               ktime_get_ts(&now);
+               now_ns = timespec_to_ns(&now);
+               delta = user_ns.clock - now_ns;
+               kvm->arch.kvmclock_offset = delta;
+               break;
+       }
+       case KVM_GET_CLOCK: {
+               struct timespec now;
+               struct kvm_clock_data user_ns;
+               u64 now_ns;
+
+               ktime_get_ts(&now);
+               now_ns = timespec_to_ns(&now);
+               user_ns.clock = kvm->arch.kvmclock_offset + now_ns;
+               user_ns.flags = 0;
+
+               r = -EFAULT;
+               if (copy_to_user(argp, &user_ns, sizeof(user_ns)))
+                       goto out;
+               r = 0;
+               break;
+       }
+
        default:
                ;
        }
@@ -3144,8 +3486,12 @@ static void kvm_timer_init(void)
        if (!boot_cpu_has(X86_FEATURE_CONSTANT_TSC)) {
                cpufreq_register_notifier(&kvmclock_cpufreq_notifier_block,
                                          CPUFREQ_TRANSITION_NOTIFIER);
-               for_each_online_cpu(cpu)
-                       per_cpu(cpu_tsc_khz, cpu) = cpufreq_get(cpu);
+               for_each_online_cpu(cpu) {
+                       unsigned long khz = cpufreq_get(cpu);
+                       if (!khz)
+                               khz = tsc_khz;
+                       per_cpu(cpu_tsc_khz, cpu) = khz;
+               }
        } else {
                for_each_possible_cpu(cpu)
                        per_cpu(cpu_tsc_khz, cpu) = tsc_khz;
@@ -3321,7 +3667,6 @@ unsigned long realmode_get_cr(struct kvm_vcpu *vcpu, int cr)
 {
        unsigned long value;
 
-       kvm_x86_ops->decache_cr4_guest_bits(vcpu);
        switch (cr) {
        case 0:
                value = vcpu->arch.cr0;
@@ -3333,7 +3678,7 @@ unsigned long realmode_get_cr(struct kvm_vcpu *vcpu, int cr)
                value = vcpu->arch.cr3;
                break;
        case 4:
-               value = vcpu->arch.cr4;
+               value = kvm_read_cr4(vcpu);
                break;
        case 8:
                value = kvm_get_cr8(vcpu);
@@ -3361,7 +3706,7 @@ void realmode_set_cr(struct kvm_vcpu *vcpu, int cr, unsigned long val,
                kvm_set_cr3(vcpu, val);
                break;
        case 4:
-               kvm_set_cr4(vcpu, mk_cr_64(vcpu->arch.cr4, val));
+               kvm_set_cr4(vcpu, mk_cr_64(kvm_read_cr4(vcpu), val));
                break;
        case 8:
                kvm_set_cr8(vcpu, val & 0xfUL);
@@ -3428,6 +3773,7 @@ struct kvm_cpuid_entry2 *kvm_find_cpuid_entry(struct kvm_vcpu *vcpu,
        }
        return best;
 }
+EXPORT_SYMBOL_GPL(kvm_find_cpuid_entry);
 
 int cpuid_maxphyaddr(struct kvm_vcpu *vcpu)
 {
@@ -3662,14 +4008,15 @@ static int vcpu_enter_guest(struct kvm_vcpu *vcpu)
        trace_kvm_entry(vcpu->vcpu_id);
        kvm_x86_ops->run(vcpu);
 
-       if (unlikely(vcpu->arch.switch_db_regs || test_thread_flag(TIF_DEBUG))) {
-               set_debugreg(current->thread.debugreg0, 0);
-               set_debugreg(current->thread.debugreg1, 1);
-               set_debugreg(current->thread.debugreg2, 2);
-               set_debugreg(current->thread.debugreg3, 3);
-               set_debugreg(current->thread.debugreg6, 6);
-               set_debugreg(current->thread.debugreg7, 7);
-       }
+       /*
+        * If the guest has used debug registers, at least dr7
+        * will be disabled while returning to the host.
+        * If we don't have active breakpoints in the host, we don't
+        * care about the messed up debug address registers. But if
+        * we have some of them active, restore the old state.
+        */
+       if (hw_breakpoint_active())
+               hw_breakpoint_restore();
 
        set_bit(KVM_REQ_KICK, &vcpu->requests);
        local_irq_enable();
@@ -3806,7 +4153,6 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run)
                if (r)
                        goto out;
        }
-#if CONFIG_HAS_IOMEM
        if (vcpu->mmio_needed) {
                memcpy(vcpu->mmio_data, kvm_run->mmio.data, 8);
                vcpu->mmio_read_completed = 1;
@@ -3824,7 +4170,6 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run)
                        goto out;
                }
        }
-#endif
        if (kvm_run->exit_reason == KVM_EXIT_HYPERCALL)
                kvm_register_write(vcpu, VCPU_REGS_RAX,
                                     kvm_run->hypercall.ret);
@@ -3943,11 +4288,10 @@ int kvm_arch_vcpu_ioctl_get_sregs(struct kvm_vcpu *vcpu,
        sregs->gdt.limit = dt.limit;
        sregs->gdt.base = dt.base;
 
-       kvm_x86_ops->decache_cr4_guest_bits(vcpu);
        sregs->cr0 = vcpu->arch.cr0;
        sregs->cr2 = vcpu->arch.cr2;
        sregs->cr3 = vcpu->arch.cr3;
-       sregs->cr4 = vcpu->arch.cr4;
+       sregs->cr4 = kvm_read_cr4(vcpu);
        sregs->cr8 = kvm_get_cr8(vcpu);
        sregs->efer = vcpu->arch.shadow_efer;
        sregs->apic_base = kvm_get_apic_base(vcpu);
@@ -4116,6 +4460,15 @@ static int is_vm86_segment(struct kvm_vcpu *vcpu, int seg)
                (kvm_get_rflags(vcpu) & X86_EFLAGS_VM);
 }
 
+static void kvm_check_segment_descriptor(struct kvm_vcpu *vcpu, int seg,
+                                        u16 selector)
+{
+       /* NULL selector is not valid for CS and SS */
+       if (seg == VCPU_SREG_CS || seg == VCPU_SREG_SS)
+               if (!selector)
+                       kvm_queue_exception_e(vcpu, TS_VECTOR, selector >> 3);
+}
+
 int kvm_load_segment_descriptor(struct kvm_vcpu *vcpu, u16 selector,
                                int type_bits, int seg)
 {
@@ -4125,6 +4478,8 @@ int kvm_load_segment_descriptor(struct kvm_vcpu *vcpu, u16 selector,
                return kvm_load_realmode_segment(vcpu, selector, seg);
        if (load_segment_descriptor_to_kvm_desct(vcpu, selector, &kvm_seg))
                return 1;
+
+       kvm_check_segment_descriptor(vcpu, seg, selector);
        kvm_seg.type |= type_bits;
 
        if (seg != VCPU_SREG_SS && seg != VCPU_SREG_CS &&
@@ -4379,11 +4734,6 @@ int kvm_task_switch(struct kvm_vcpu *vcpu, u16 tss_selector, int reason)
        if (reason != TASK_SWITCH_CALL && reason != TASK_SWITCH_GATE)
                old_tss_sel = 0xffff;
 
-       /* set back link to prev task only if NT bit is set in eflags
-          note that old_tss_sel is not used afetr this point */
-       if (reason != TASK_SWITCH_CALL && reason != TASK_SWITCH_GATE)
-               old_tss_sel = 0xffff;
-
        if (nseg_desc.type & 8)
                ret = kvm_task_switch_32(vcpu, tss_selector, old_tss_sel,
                                         old_tss_base, &nseg_desc);
@@ -4437,16 +4787,16 @@ int kvm_arch_vcpu_ioctl_set_sregs(struct kvm_vcpu *vcpu,
        kvm_x86_ops->set_efer(vcpu, sregs->efer);
        kvm_set_apic_base(vcpu, sregs->apic_base);
 
-       kvm_x86_ops->decache_cr4_guest_bits(vcpu);
-
        mmu_reset_needed |= vcpu->arch.cr0 != sregs->cr0;
        kvm_x86_ops->set_cr0(vcpu, sregs->cr0);
        vcpu->arch.cr0 = sregs->cr0;
 
-       mmu_reset_needed |= vcpu->arch.cr4 != sregs->cr4;
+       mmu_reset_needed |= kvm_read_cr4(vcpu) != sregs->cr4;
        kvm_x86_ops->set_cr4(vcpu, sregs->cr4);
-       if (!is_long_mode(vcpu) && is_pae(vcpu))
+       if (!is_long_mode(vcpu) && is_pae(vcpu)) {
                load_pdptrs(vcpu, vcpu->arch.cr3);
+               mmu_reset_needed = 1;
+       }
 
        if (mmu_reset_needed)
                kvm_mmu_reset_context(vcpu);
@@ -4488,10 +4838,20 @@ int kvm_arch_vcpu_ioctl_set_guest_debug(struct kvm_vcpu *vcpu,
                                        struct kvm_guest_debug *dbg)
 {
        unsigned long rflags;
-       int i;
+       int i, r;
 
        vcpu_load(vcpu);
 
+       if (dbg->control & (KVM_GUESTDBG_INJECT_DB | KVM_GUESTDBG_INJECT_BP)) {
+               r = -EBUSY;
+               if (vcpu->arch.exception.pending)
+                       goto unlock_out;
+               if (dbg->control & KVM_GUESTDBG_INJECT_DB)
+                       kvm_queue_exception(vcpu, DB_VECTOR);
+               else
+                       kvm_queue_exception(vcpu, BP_VECTOR);
+       }
+
        /*
         * Read rflags as long as potentially injected trace flags are still
         * filtered out.
@@ -4513,6 +4873,12 @@ int kvm_arch_vcpu_ioctl_set_guest_debug(struct kvm_vcpu *vcpu,
                vcpu->arch.switch_db_regs = (vcpu->arch.dr7 & DR7_BP_EN_MASK);
        }
 
+       if (vcpu->guest_debug & KVM_GUESTDBG_SINGLESTEP) {
+               vcpu->arch.singlestep_cs =
+                       get_segment_selector(vcpu, VCPU_SREG_CS);
+               vcpu->arch.singlestep_rip = kvm_rip_read(vcpu);
+       }
+
        /*
         * Trigger an rflags update that will inject or remove the trace
         * flags.
@@ -4521,14 +4887,12 @@ int kvm_arch_vcpu_ioctl_set_guest_debug(struct kvm_vcpu *vcpu,
 
        kvm_x86_ops->set_guest_debug(vcpu, dbg);
 
-       if (vcpu->guest_debug & KVM_GUESTDBG_INJECT_DB)
-               kvm_queue_exception(vcpu, DB_VECTOR);
-       else if (vcpu->guest_debug & KVM_GUESTDBG_INJECT_BP)
-               kvm_queue_exception(vcpu, BP_VECTOR);
+       r = 0;
 
+unlock_out:
        vcpu_put(vcpu);
 
-       return 0;
+       return r;
 }
 
 /*
@@ -4736,12 +5100,16 @@ int kvm_arch_hardware_enable(void *garbage)
                int cpu = raw_smp_processor_id();
                per_cpu(cpu_tsc_khz, cpu) = 0;
        }
+
+       kvm_shared_msr_cpu_online();
+
        return kvm_x86_ops->hardware_enable(garbage);
 }
 
 void kvm_arch_hardware_disable(void *garbage)
 {
        kvm_x86_ops->hardware_disable(garbage);
+       drop_user_return_notifiers(garbage);
 }
 
 int kvm_arch_hardware_setup(void)
@@ -4795,12 +5163,13 @@ int kvm_arch_vcpu_init(struct kvm_vcpu *vcpu)
                                       GFP_KERNEL);
        if (!vcpu->arch.mce_banks) {
                r = -ENOMEM;
-               goto fail_mmu_destroy;
+               goto fail_free_lapic;
        }
        vcpu->arch.mcg_cap = KVM_MAX_MCE_BANKS;
 
        return 0;
-
+fail_free_lapic:
+       kvm_free_lapic(vcpu);
 fail_mmu_destroy:
        kvm_mmu_destroy(vcpu);
 fail_free_pio_data:
@@ -4811,6 +5180,7 @@ fail:
 
 void kvm_arch_vcpu_uninit(struct kvm_vcpu *vcpu)
 {
+       kfree(vcpu->arch.mce_banks);
        kvm_free_lapic(vcpu);
        down_read(&vcpu->kvm->slots_lock);
        kvm_mmu_destroy(vcpu);
@@ -4825,6 +5195,12 @@ struct  kvm *kvm_arch_create_vm(void)
        if (!kvm)
                return ERR_PTR(-ENOMEM);
 
+       kvm->arch.aliases = kzalloc(sizeof(struct kvm_mem_aliases), GFP_KERNEL);
+       if (!kvm->arch.aliases) {
+               kfree(kvm);
+               return ERR_PTR(-ENOMEM);
+       }
+
        INIT_LIST_HEAD(&kvm->arch.active_mmu_pages);
        INIT_LIST_HEAD(&kvm->arch.assigned_dev_head);
 
@@ -4881,16 +5257,17 @@ void kvm_arch_destroy_vm(struct kvm *kvm)
                put_page(kvm->arch.apic_access_page);
        if (kvm->arch.ept_identity_pagetable)
                put_page(kvm->arch.ept_identity_pagetable);
+       kfree(kvm->arch.aliases);
        kfree(kvm);
 }
 
-int kvm_arch_set_memory_region(struct kvm *kvm,
-                               struct kvm_userspace_memory_region *mem,
+int kvm_arch_prepare_memory_region(struct kvm *kvm,
+                               struct kvm_memory_slot *memslot,
                                struct kvm_memory_slot old,
+                               struct kvm_userspace_memory_region *mem,
                                int user_alloc)
 {
-       int npages = mem->memory_size >> PAGE_SHIFT;
-       struct kvm_memory_slot *memslot = &kvm->memslots[mem->slot];
+       int npages = memslot->npages;
 
        /*To keep backward compatibility with older userspace,
         *x86 needs to hanlde !user_alloc case.
@@ -4910,26 +5287,35 @@ int kvm_arch_set_memory_region(struct kvm *kvm,
                        if (IS_ERR((void *)userspace_addr))
                                return PTR_ERR((void *)userspace_addr);
 
-                       /* set userspace_addr atomically for kvm_hva_to_rmapp */
-                       spin_lock(&kvm->mmu_lock);
                        memslot->userspace_addr = userspace_addr;
-                       spin_unlock(&kvm->mmu_lock);
-               } else {
-                       if (!old.user_alloc && old.rmap) {
-                               int ret;
-
-                               down_write(&current->mm->mmap_sem);
-                               ret = do_munmap(current->mm, old.userspace_addr,
-                                               old.npages * PAGE_SIZE);
-                               up_write(&current->mm->mmap_sem);
-                               if (ret < 0)
-                                       printk(KERN_WARNING
-                                      "kvm_vm_ioctl_set_memory_region: "
-                                      "failed to munmap memory\n");
-                       }
                }
        }
 
+
+       return 0;
+}
+
+void kvm_arch_commit_memory_region(struct kvm *kvm,
+                               struct kvm_userspace_memory_region *mem,
+                               struct kvm_memory_slot old,
+                               int user_alloc)
+{
+
+       int npages = mem->memory_size >> PAGE_SHIFT;
+
+       if (!user_alloc && !old.user_alloc && old.rmap && !npages) {
+               int ret;
+
+               down_write(&current->mm->mmap_sem);
+               ret = do_munmap(current->mm, old.userspace_addr,
+                               old.npages * PAGE_SIZE);
+               up_write(&current->mm->mmap_sem);
+               if (ret < 0)
+                       printk(KERN_WARNING
+                              "kvm_vm_ioctl_set_memory_region: "
+                              "failed to munmap memory\n");
+       }
+
        spin_lock(&kvm->mmu_lock);
        if (!kvm->arch.n_requested_mmu_pages) {
                unsigned int nr_mmu_pages = kvm_mmu_calculate_mmu_pages(kvm);
@@ -4938,8 +5324,6 @@ int kvm_arch_set_memory_region(struct kvm *kvm,
 
        kvm_mmu_slot_remove_write_access(kvm, mem->slot);
        spin_unlock(&kvm->mmu_lock);
-
-       return 0;
 }
 
 void kvm_arch_flush_shadow(struct kvm *kvm)
@@ -4979,6 +5363,28 @@ int kvm_arch_interrupt_allowed(struct kvm_vcpu *vcpu)
        return kvm_x86_ops->interrupt_allowed(vcpu);
 }
 
+unsigned long kvm_get_rflags(struct kvm_vcpu *vcpu)
+{
+       unsigned long rflags;
+
+       rflags = kvm_x86_ops->get_rflags(vcpu);
+       if (vcpu->guest_debug & KVM_GUESTDBG_SINGLESTEP)
+               rflags &= ~(unsigned long)(X86_EFLAGS_TF | X86_EFLAGS_RF);
+       return rflags;
+}
+EXPORT_SYMBOL_GPL(kvm_get_rflags);
+
+void kvm_set_rflags(struct kvm_vcpu *vcpu, unsigned long rflags)
+{
+       if (vcpu->guest_debug & KVM_GUESTDBG_SINGLESTEP &&
+           vcpu->arch.singlestep_cs ==
+                       get_segment_selector(vcpu, VCPU_SREG_CS) &&
+           vcpu->arch.singlestep_rip == kvm_rip_read(vcpu))
+               rflags |= X86_EFLAGS_TF | X86_EFLAGS_RF;
+       kvm_x86_ops->set_rflags(vcpu, rflags);
+}
+EXPORT_SYMBOL_GPL(kvm_set_rflags);
+
 EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_exit);
 EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_inj_virq);
 EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_page_fault);