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Diffstat (limited to 'arch/x86/kvm/x86.c')
-rw-r--r--arch/x86/kvm/x86.c796
1 files changed, 610 insertions, 186 deletions
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 6c2ecf0a806..cdac9e592aa 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -6,7 +6,7 @@
* Copyright (C) 2006 Qumranet, Inc.
* Copyright (C) 2008 Qumranet, Inc.
* Copyright IBM Corporation, 2008
- * Copyright 2010 Red Hat, Inc. and/or its affilates.
+ * Copyright 2010 Red Hat, Inc. and/or its affiliates.
*
* Authors:
* Avi Kivity <avi@qumranet.com>
@@ -55,6 +55,8 @@
#include <asm/mce.h>
#include <asm/i387.h>
#include <asm/xcr.h>
+#include <asm/pvclock.h>
+#include <asm/div64.h>
#define MAX_IO_MSRS 256
#define CR0_RESERVED_BITS \
@@ -71,7 +73,7 @@
#define CR8_RESERVED_BITS (~(unsigned long)X86_CR8_TPR)
#define KVM_MAX_MCE_BANKS 32
-#define KVM_MCE_CAP_SUPPORTED MCG_CTL_P
+#define KVM_MCE_CAP_SUPPORTED (MCG_CTL_P | MCG_SER_P)
/* EFER defaults:
* - enable syscall per default because its emulated by KVM
@@ -282,6 +284,8 @@ static void kvm_multiple_exception(struct kvm_vcpu *vcpu,
u32 prev_nr;
int class1, class2;
+ kvm_make_request(KVM_REQ_EVENT, vcpu);
+
if (!vcpu->arch.exception.pending) {
queue:
vcpu->arch.exception.pending = true;
@@ -327,16 +331,28 @@ void kvm_requeue_exception(struct kvm_vcpu *vcpu, unsigned nr)
}
EXPORT_SYMBOL_GPL(kvm_requeue_exception);
-void kvm_inject_page_fault(struct kvm_vcpu *vcpu, unsigned long addr,
- u32 error_code)
+void kvm_inject_page_fault(struct kvm_vcpu *vcpu)
{
+ unsigned error_code = vcpu->arch.fault.error_code;
+
++vcpu->stat.pf_guest;
- vcpu->arch.cr2 = addr;
+ vcpu->arch.cr2 = vcpu->arch.fault.address;
kvm_queue_exception_e(vcpu, PF_VECTOR, error_code);
}
+void kvm_propagate_fault(struct kvm_vcpu *vcpu)
+{
+ if (mmu_is_nested(vcpu) && !vcpu->arch.fault.nested)
+ vcpu->arch.nested_mmu.inject_page_fault(vcpu);
+ else
+ vcpu->arch.mmu.inject_page_fault(vcpu);
+
+ vcpu->arch.fault.nested = false;
+}
+
void kvm_inject_nmi(struct kvm_vcpu *vcpu)
{
+ kvm_make_request(KVM_REQ_EVENT, vcpu);
vcpu->arch.nmi_pending = 1;
}
EXPORT_SYMBOL_GPL(kvm_inject_nmi);
@@ -367,18 +383,49 @@ bool kvm_require_cpl(struct kvm_vcpu *vcpu, int required_cpl)
EXPORT_SYMBOL_GPL(kvm_require_cpl);
/*
+ * This function will be used to read from the physical memory of the currently
+ * running guest. The difference to kvm_read_guest_page is that this function
+ * can read from guest physical or from the guest's guest physical memory.
+ */
+int kvm_read_guest_page_mmu(struct kvm_vcpu *vcpu, struct kvm_mmu *mmu,
+ gfn_t ngfn, void *data, int offset, int len,
+ u32 access)
+{
+ gfn_t real_gfn;
+ gpa_t ngpa;
+
+ ngpa = gfn_to_gpa(ngfn);
+ real_gfn = mmu->translate_gpa(vcpu, ngpa, access);
+ if (real_gfn == UNMAPPED_GVA)
+ return -EFAULT;
+
+ real_gfn = gpa_to_gfn(real_gfn);
+
+ return kvm_read_guest_page(vcpu->kvm, real_gfn, data, offset, len);
+}
+EXPORT_SYMBOL_GPL(kvm_read_guest_page_mmu);
+
+int kvm_read_nested_guest_page(struct kvm_vcpu *vcpu, gfn_t gfn,
+ void *data, int offset, int len, u32 access)
+{
+ return kvm_read_guest_page_mmu(vcpu, vcpu->arch.walk_mmu, gfn,
+ data, offset, len, access);
+}
+
+/*
* Load the pae pdptrs. Return true is they are all valid.
*/
-int load_pdptrs(struct kvm_vcpu *vcpu, unsigned long cr3)
+int load_pdptrs(struct kvm_vcpu *vcpu, struct kvm_mmu *mmu, unsigned long cr3)
{
gfn_t pdpt_gfn = cr3 >> PAGE_SHIFT;
unsigned offset = ((cr3 & (PAGE_SIZE-1)) >> 5) << 2;
int i;
int ret;
- u64 pdpte[ARRAY_SIZE(vcpu->arch.pdptrs)];
+ u64 pdpte[ARRAY_SIZE(mmu->pdptrs)];
- ret = kvm_read_guest_page(vcpu->kvm, pdpt_gfn, pdpte,
- offset * sizeof(u64), sizeof(pdpte));
+ ret = kvm_read_guest_page_mmu(vcpu, mmu, pdpt_gfn, pdpte,
+ offset * sizeof(u64), sizeof(pdpte),
+ PFERR_USER_MASK|PFERR_WRITE_MASK);
if (ret < 0) {
ret = 0;
goto out;
@@ -392,7 +439,7 @@ int load_pdptrs(struct kvm_vcpu *vcpu, unsigned long cr3)
}
ret = 1;
- memcpy(vcpu->arch.pdptrs, pdpte, sizeof(vcpu->arch.pdptrs));
+ memcpy(mmu->pdptrs, pdpte, sizeof(mmu->pdptrs));
__set_bit(VCPU_EXREG_PDPTR,
(unsigned long *)&vcpu->arch.regs_avail);
__set_bit(VCPU_EXREG_PDPTR,
@@ -405,8 +452,10 @@ EXPORT_SYMBOL_GPL(load_pdptrs);
static bool pdptrs_changed(struct kvm_vcpu *vcpu)
{
- u64 pdpte[ARRAY_SIZE(vcpu->arch.pdptrs)];
+ u64 pdpte[ARRAY_SIZE(vcpu->arch.walk_mmu->pdptrs)];
bool changed = true;
+ int offset;
+ gfn_t gfn;
int r;
if (is_long_mode(vcpu) || !is_pae(vcpu))
@@ -416,10 +465,13 @@ static bool pdptrs_changed(struct kvm_vcpu *vcpu)
(unsigned long *)&vcpu->arch.regs_avail))
return true;
- r = kvm_read_guest(vcpu->kvm, vcpu->arch.cr3 & ~31u, pdpte, sizeof(pdpte));
+ gfn = (vcpu->arch.cr3 & ~31u) >> PAGE_SHIFT;
+ offset = (vcpu->arch.cr3 & ~31u) & (PAGE_SIZE - 1);
+ r = kvm_read_nested_guest_page(vcpu, gfn, pdpte, offset, sizeof(pdpte),
+ PFERR_USER_MASK | PFERR_WRITE_MASK);
if (r < 0)
goto out;
- changed = memcmp(pdpte, vcpu->arch.pdptrs, sizeof(pdpte)) != 0;
+ changed = memcmp(pdpte, vcpu->arch.walk_mmu->pdptrs, sizeof(pdpte)) != 0;
out:
return changed;
@@ -458,7 +510,8 @@ int kvm_set_cr0(struct kvm_vcpu *vcpu, unsigned long cr0)
return 1;
} else
#endif
- if (is_pae(vcpu) && !load_pdptrs(vcpu, vcpu->arch.cr3))
+ if (is_pae(vcpu) && !load_pdptrs(vcpu, vcpu->arch.walk_mmu,
+ vcpu->arch.cr3))
return 1;
}
@@ -547,7 +600,7 @@ int kvm_set_cr4(struct kvm_vcpu *vcpu, unsigned long cr4)
return 1;
} else if (is_paging(vcpu) && (cr4 & X86_CR4_PAE)
&& ((cr4 ^ old_cr4) & pdptr_bits)
- && !load_pdptrs(vcpu, vcpu->arch.cr3))
+ && !load_pdptrs(vcpu, vcpu->arch.walk_mmu, vcpu->arch.cr3))
return 1;
if (cr4 & X86_CR4_VMXE)
@@ -580,7 +633,8 @@ int kvm_set_cr3(struct kvm_vcpu *vcpu, unsigned long cr3)
if (is_pae(vcpu)) {
if (cr3 & CR3_PAE_RESERVED_BITS)
return 1;
- if (is_paging(vcpu) && !load_pdptrs(vcpu, cr3))
+ if (is_paging(vcpu) &&
+ !load_pdptrs(vcpu, vcpu->arch.walk_mmu, cr3))
return 1;
}
/*
@@ -737,7 +791,7 @@ static u32 msrs_to_save[] = {
#ifdef CONFIG_X86_64
MSR_CSTAR, MSR_KERNEL_GS_BASE, MSR_SYSCALL_MASK, MSR_LSTAR,
#endif
- MSR_IA32_TSC, MSR_IA32_PERF_STATUS, MSR_IA32_CR_PAT, MSR_VM_HSAVE_PA
+ MSR_IA32_TSC, MSR_IA32_CR_PAT, MSR_VM_HSAVE_PA
};
static unsigned num_msrs_to_save;
@@ -838,7 +892,7 @@ static void kvm_write_wall_clock(struct kvm *kvm, gpa_t wall_clock)
/*
* The guest calculates current wall clock time by adding
- * system time (updated by kvm_write_guest_time below) to the
+ * system time (updated by kvm_guest_time_update below) to the
* wall clock specified here. guest system time equals host
* system time for us, thus we must fill in host boot time here.
*/
@@ -866,65 +920,229 @@ static uint32_t div_frac(uint32_t dividend, uint32_t divisor)
return quotient;
}
-static void kvm_set_time_scale(uint32_t tsc_khz, struct pvclock_vcpu_time_info *hv_clock)
+static void kvm_get_time_scale(uint32_t scaled_khz, uint32_t base_khz,
+ s8 *pshift, u32 *pmultiplier)
{
- uint64_t nsecs = 1000000000LL;
+ uint64_t scaled64;
int32_t shift = 0;
uint64_t tps64;
uint32_t tps32;
- tps64 = tsc_khz * 1000LL;
- while (tps64 > nsecs*2) {
+ tps64 = base_khz * 1000LL;
+ scaled64 = scaled_khz * 1000LL;
+ while (tps64 > scaled64*2 || tps64 & 0xffffffff00000000ULL) {
tps64 >>= 1;
shift--;
}
tps32 = (uint32_t)tps64;
- while (tps32 <= (uint32_t)nsecs) {
- tps32 <<= 1;
+ while (tps32 <= scaled64 || scaled64 & 0xffffffff00000000ULL) {
+ if (scaled64 & 0xffffffff00000000ULL || tps32 & 0x80000000)
+ scaled64 >>= 1;
+ else
+ tps32 <<= 1;
shift++;
}
- hv_clock->tsc_shift = shift;
- hv_clock->tsc_to_system_mul = div_frac(nsecs, tps32);
+ *pshift = shift;
+ *pmultiplier = div_frac(scaled64, tps32);
+
+ pr_debug("%s: base_khz %u => %u, shift %d, mul %u\n",
+ __func__, base_khz, scaled_khz, shift, *pmultiplier);
+}
+
+static inline u64 get_kernel_ns(void)
+{
+ struct timespec ts;
- pr_debug("%s: tsc_khz %u, tsc_shift %d, tsc_mul %u\n",
- __func__, tsc_khz, hv_clock->tsc_shift,
- hv_clock->tsc_to_system_mul);
+ WARN_ON(preemptible());
+ ktime_get_ts(&ts);
+ monotonic_to_bootbased(&ts);
+ return timespec_to_ns(&ts);
}
static DEFINE_PER_CPU(unsigned long, cpu_tsc_khz);
+unsigned long max_tsc_khz;
-static void kvm_write_guest_time(struct kvm_vcpu *v)
+static inline int kvm_tsc_changes_freq(void)
+{
+ int cpu = get_cpu();
+ int ret = !boot_cpu_has(X86_FEATURE_CONSTANT_TSC) &&
+ cpufreq_quick_get(cpu) != 0;
+ put_cpu();
+ return ret;
+}
+
+static inline u64 nsec_to_cycles(u64 nsec)
+{
+ u64 ret;
+
+ WARN_ON(preemptible());
+ if (kvm_tsc_changes_freq())
+ printk_once(KERN_WARNING
+ "kvm: unreliable cycle conversion on adjustable rate TSC\n");
+ ret = nsec * __get_cpu_var(cpu_tsc_khz);
+ do_div(ret, USEC_PER_SEC);
+ return ret;
+}
+
+static void kvm_arch_set_tsc_khz(struct kvm *kvm, u32 this_tsc_khz)
+{
+ /* Compute a scale to convert nanoseconds in TSC cycles */
+ kvm_get_time_scale(this_tsc_khz, NSEC_PER_SEC / 1000,
+ &kvm->arch.virtual_tsc_shift,
+ &kvm->arch.virtual_tsc_mult);
+ kvm->arch.virtual_tsc_khz = this_tsc_khz;
+}
+
+static u64 compute_guest_tsc(struct kvm_vcpu *vcpu, s64 kernel_ns)
+{
+ u64 tsc = pvclock_scale_delta(kernel_ns-vcpu->arch.last_tsc_nsec,
+ vcpu->kvm->arch.virtual_tsc_mult,
+ vcpu->kvm->arch.virtual_tsc_shift);
+ tsc += vcpu->arch.last_tsc_write;
+ return tsc;
+}
+
+void kvm_write_tsc(struct kvm_vcpu *vcpu, u64 data)
+{
+ struct kvm *kvm = vcpu->kvm;
+ u64 offset, ns, elapsed;
+ unsigned long flags;
+ s64 sdiff;
+
+ spin_lock_irqsave(&kvm->arch.tsc_write_lock, flags);
+ offset = data - native_read_tsc();
+ ns = get_kernel_ns();
+ elapsed = ns - kvm->arch.last_tsc_nsec;
+ sdiff = data - kvm->arch.last_tsc_write;
+ if (sdiff < 0)
+ sdiff = -sdiff;
+
+ /*
+ * Special case: close write to TSC within 5 seconds of
+ * another CPU is interpreted as an attempt to synchronize
+ * The 5 seconds is to accomodate host load / swapping as
+ * well as any reset of TSC during the boot process.
+ *
+ * In that case, for a reliable TSC, we can match TSC offsets,
+ * or make a best guest using elapsed value.
+ */
+ if (sdiff < nsec_to_cycles(5ULL * NSEC_PER_SEC) &&
+ elapsed < 5ULL * NSEC_PER_SEC) {
+ if (!check_tsc_unstable()) {
+ offset = kvm->arch.last_tsc_offset;
+ pr_debug("kvm: matched tsc offset for %llu\n", data);
+ } else {
+ u64 delta = nsec_to_cycles(elapsed);
+ offset += delta;
+ pr_debug("kvm: adjusted tsc offset by %llu\n", delta);
+ }
+ ns = kvm->arch.last_tsc_nsec;
+ }
+ kvm->arch.last_tsc_nsec = ns;
+ kvm->arch.last_tsc_write = data;
+ kvm->arch.last_tsc_offset = offset;
+ kvm_x86_ops->write_tsc_offset(vcpu, offset);
+ spin_unlock_irqrestore(&kvm->arch.tsc_write_lock, flags);
+
+ /* Reset of TSC must disable overshoot protection below */
+ vcpu->arch.hv_clock.tsc_timestamp = 0;
+ vcpu->arch.last_tsc_write = data;
+ vcpu->arch.last_tsc_nsec = ns;
+}
+EXPORT_SYMBOL_GPL(kvm_write_tsc);
+
+static int kvm_guest_time_update(struct kvm_vcpu *v)
{
- struct timespec ts;
unsigned long flags;
struct kvm_vcpu_arch *vcpu = &v->arch;
void *shared_kaddr;
unsigned long this_tsc_khz;
+ s64 kernel_ns, max_kernel_ns;
+ u64 tsc_timestamp;
- if ((!vcpu->time_page))
- return;
+ /* Keep irq disabled to prevent changes to the clock */
+ local_irq_save(flags);
+ kvm_get_msr(v, MSR_IA32_TSC, &tsc_timestamp);
+ kernel_ns = get_kernel_ns();
+ this_tsc_khz = __get_cpu_var(cpu_tsc_khz);
- this_tsc_khz = get_cpu_var(cpu_tsc_khz);
- if (unlikely(vcpu->hv_clock_tsc_khz != this_tsc_khz)) {
- kvm_set_time_scale(this_tsc_khz, &vcpu->hv_clock);
- vcpu->hv_clock_tsc_khz = this_tsc_khz;
+ if (unlikely(this_tsc_khz == 0)) {
+ local_irq_restore(flags);
+ kvm_make_request(KVM_REQ_CLOCK_UPDATE, v);
+ return 1;
+ }
+
+ /*
+ * We may have to catch up the TSC to match elapsed wall clock
+ * time for two reasons, even if kvmclock is used.
+ * 1) CPU could have been running below the maximum TSC rate
+ * 2) Broken TSC compensation resets the base at each VCPU
+ * entry to avoid unknown leaps of TSC even when running
+ * again on the same CPU. This may cause apparent elapsed
+ * time to disappear, and the guest to stand still or run
+ * very slowly.
+ */
+ if (vcpu->tsc_catchup) {
+ u64 tsc = compute_guest_tsc(v, kernel_ns);
+ if (tsc > tsc_timestamp) {
+ kvm_x86_ops->adjust_tsc_offset(v, tsc - tsc_timestamp);
+ tsc_timestamp = tsc;
+ }
}
- put_cpu_var(cpu_tsc_khz);
- /* Keep irq disabled to prevent changes to the clock */
- 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 */
+ if (!vcpu->time_page)
+ return 0;
+
+ /*
+ * Time as measured by the TSC may go backwards when resetting the base
+ * tsc_timestamp. The reason for this is that the TSC resolution is
+ * higher than the resolution of the other clock scales. Thus, many
+ * possible measurments of the TSC correspond to one measurement of any
+ * other clock, and so a spread of values is possible. This is not a
+ * problem for the computation of the nanosecond clock; with TSC rates
+ * around 1GHZ, there can only be a few cycles which correspond to one
+ * nanosecond value, and any path through this code will inevitably
+ * take longer than that. However, with the kernel_ns value itself,
+ * the precision may be much lower, down to HZ granularity. If the
+ * first sampling of TSC against kernel_ns ends in the low part of the
+ * range, and the second in the high end of the range, we can get:
+ *
+ * (TSC - offset_low) * S + kns_old > (TSC - offset_high) * S + kns_new
+ *
+ * As the sampling errors potentially range in the thousands of cycles,
+ * it is possible such a time value has already been observed by the
+ * guest. To protect against this, we must compute the system time as
+ * observed by the guest and ensure the new system time is greater.
+ */
+ max_kernel_ns = 0;
+ if (vcpu->hv_clock.tsc_timestamp && vcpu->last_guest_tsc) {
+ max_kernel_ns = vcpu->last_guest_tsc -
+ vcpu->hv_clock.tsc_timestamp;
+ max_kernel_ns = pvclock_scale_delta(max_kernel_ns,
+ vcpu->hv_clock.tsc_to_system_mul,
+ vcpu->hv_clock.tsc_shift);
+ max_kernel_ns += vcpu->last_kernel_ns;
+ }
+
+ if (unlikely(vcpu->hw_tsc_khz != this_tsc_khz)) {
+ kvm_get_time_scale(NSEC_PER_SEC / 1000, this_tsc_khz,
+ &vcpu->hv_clock.tsc_shift,
+ &vcpu->hv_clock.tsc_to_system_mul);
+ vcpu->hw_tsc_khz = this_tsc_khz;
+ }
- vcpu->hv_clock.system_time = ts.tv_nsec +
- (NSEC_PER_SEC * (u64)ts.tv_sec) + v->kvm->arch.kvmclock_offset;
+ if (max_kernel_ns > kernel_ns)
+ kernel_ns = max_kernel_ns;
+ /* With all the info we got, fill in the values */
+ vcpu->hv_clock.tsc_timestamp = tsc_timestamp;
+ vcpu->hv_clock.system_time = kernel_ns + v->kvm->arch.kvmclock_offset;
+ vcpu->last_kernel_ns = kernel_ns;
+ vcpu->last_guest_tsc = tsc_timestamp;
vcpu->hv_clock.flags = 0;
/*
@@ -942,16 +1160,7 @@ static void kvm_write_guest_time(struct kvm_vcpu *v)
kunmap_atomic(shared_kaddr, KM_USER0);
mark_page_dirty(v->kvm, vcpu->time >> PAGE_SHIFT);
-}
-
-static int kvm_request_guest_time_update(struct kvm_vcpu *v)
-{
- struct kvm_vcpu_arch *vcpu = &v->arch;
-
- if (!vcpu->time_page)
- return 0;
- kvm_make_request(KVM_REQ_KVMCLOCK_UPDATE, v);
- return 1;
+ return 0;
}
static bool msr_mtrr_valid(unsigned msr)
@@ -1277,6 +1486,7 @@ int kvm_set_msr_common(struct kvm_vcpu *vcpu, u32 msr, u64 data)
}
vcpu->arch.time = data;
+ kvm_make_request(KVM_REQ_CLOCK_UPDATE, vcpu);
/* we verify if the enable bit is set... */
if (!(data & 1))
@@ -1292,8 +1502,6 @@ int kvm_set_msr_common(struct kvm_vcpu *vcpu, u32 msr, u64 data)
kvm_release_page_clean(vcpu->arch.time_page);
vcpu->arch.time_page = NULL;
}
-
- kvm_request_guest_time_update(vcpu);
break;
}
case MSR_IA32_MCG_CTL:
@@ -1330,6 +1538,16 @@ int kvm_set_msr_common(struct kvm_vcpu *vcpu, u32 msr, u64 data)
pr_unimpl(vcpu, "unimplemented perfctr wrmsr: "
"0x%x data 0x%llx\n", msr, data);
break;
+ case MSR_K7_CLK_CTL:
+ /*
+ * Ignore all writes to this no longer documented MSR.
+ * Writes are only relevant for old K7 processors,
+ * all pre-dating SVM, but a recommended workaround from
+ * AMD for these chips. It is possible to speicify the
+ * affected processor models on the command line, hence
+ * the need to ignore the workaround.
+ */
+ break;
case HV_X64_MSR_GUEST_OS_ID ... HV_X64_MSR_SINT15:
if (kvm_hv_msr_partition_wide(msr)) {
int r;
@@ -1522,6 +1740,20 @@ int kvm_get_msr_common(struct kvm_vcpu *vcpu, u32 msr, u64 *pdata)
case 0xcd: /* fsb frequency */
data = 3;
break;
+ /*
+ * MSR_EBC_FREQUENCY_ID
+ * Conservative value valid for even the basic CPU models.
+ * Models 0,1: 000 in bits 23:21 indicating a bus speed of
+ * 100MHz, model 2 000 in bits 18:16 indicating 100MHz,
+ * and 266MHz for model 3, or 4. Set Core Clock
+ * Frequency to System Bus Frequency Ratio to 1 (bits
+ * 31:24) even though these are only valid for CPU
+ * models > 2, however guests may end up dividing or
+ * multiplying by zero otherwise.
+ */
+ case MSR_EBC_FREQUENCY_ID:
+ data = 1 << 24;
+ break;
case MSR_IA32_APICBASE:
data = kvm_get_apic_base(vcpu);
break;
@@ -1555,6 +1787,18 @@ int kvm_get_msr_common(struct kvm_vcpu *vcpu, u32 msr, u64 *pdata)
case MSR_IA32_MCG_STATUS:
case MSR_IA32_MC0_CTL ... MSR_IA32_MC0_CTL + 4 * KVM_MAX_MCE_BANKS - 1:
return get_msr_mce(vcpu, msr, pdata);
+ case MSR_K7_CLK_CTL:
+ /*
+ * Provide expected ramp-up count for K7. All other
+ * are set to zero, indicating minimum divisors for
+ * every field.
+ *
+ * This prevents guest kernels on AMD host with CPU
+ * type 6, model 8 and higher from exploding due to
+ * the rdmsr failing.
+ */
+ data = 0x20000000;
+ break;
case HV_X64_MSR_GUEST_OS_ID ... HV_X64_MSR_SINT15:
if (kvm_hv_msr_partition_wide(msr)) {
int r;
@@ -1808,19 +2052,28 @@ 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)) {
- unsigned long khz = cpufreq_quick_get(cpu);
- if (!khz)
- khz = tsc_khz;
- per_cpu(cpu_tsc_khz, cpu) = khz;
+ if (unlikely(vcpu->cpu != cpu) || check_tsc_unstable()) {
+ /* Make sure TSC doesn't go backwards */
+ s64 tsc_delta = !vcpu->arch.last_host_tsc ? 0 :
+ native_read_tsc() - vcpu->arch.last_host_tsc;
+ if (tsc_delta < 0)
+ mark_tsc_unstable("KVM discovered backwards TSC");
+ if (check_tsc_unstable()) {
+ kvm_x86_ops->adjust_tsc_offset(vcpu, -tsc_delta);
+ vcpu->arch.tsc_catchup = 1;
+ kvm_make_request(KVM_REQ_CLOCK_UPDATE, vcpu);
+ }
+ if (vcpu->cpu != cpu)
+ kvm_migrate_timers(vcpu);
+ vcpu->cpu = cpu;
}
- kvm_request_guest_time_update(vcpu);
}
void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu)
{
kvm_x86_ops->vcpu_put(vcpu);
kvm_put_guest_fpu(vcpu);
+ vcpu->arch.last_host_tsc = native_read_tsc();
}
static int is_efer_nx(void)
@@ -1995,7 +2248,7 @@ static void do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 function,
F(F16C);
/* cpuid 0x80000001.ecx */
const u32 kvm_supported_word6_x86_features =
- F(LAHF_LM) | F(CMP_LEGACY) | F(SVM) | 0 /* ExtApicSpace */ |
+ F(LAHF_LM) | F(CMP_LEGACY) | 0 /*SVM*/ | 0 /* ExtApicSpace */ |
F(CR8_LEGACY) | F(ABM) | F(SSE4A) | F(MISALIGNSSE) |
F(3DNOWPREFETCH) | 0 /* OSVW */ | 0 /* IBS */ | F(XOP) |
0 /* SKINIT, WDT, LWP */ | F(FMA4) | F(TBM);
@@ -2204,6 +2457,7 @@ static int kvm_vcpu_ioctl_interrupt(struct kvm_vcpu *vcpu,
return -ENXIO;
kvm_queue_interrupt(vcpu, irq->irq, false);
+ kvm_make_request(KVM_REQ_EVENT, vcpu);
return 0;
}
@@ -2306,6 +2560,7 @@ static void kvm_vcpu_ioctl_x86_get_vcpu_events(struct kvm_vcpu *vcpu,
!kvm_exception_is_soft(vcpu->arch.exception.nr);
events->exception.nr = vcpu->arch.exception.nr;
events->exception.has_error_code = vcpu->arch.exception.has_error_code;
+ events->exception.pad = 0;
events->exception.error_code = vcpu->arch.exception.error_code;
events->interrupt.injected =
@@ -2319,12 +2574,14 @@ static void kvm_vcpu_ioctl_x86_get_vcpu_events(struct kvm_vcpu *vcpu,
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->nmi.pad = 0;
events->sipi_vector = vcpu->arch.sipi_vector;
events->flags = (KVM_VCPUEVENT_VALID_NMI_PENDING
| KVM_VCPUEVENT_VALID_SIPI_VECTOR
| KVM_VCPUEVENT_VALID_SHADOW);
+ memset(&events->reserved, 0, sizeof(events->reserved));
}
static int kvm_vcpu_ioctl_x86_set_vcpu_events(struct kvm_vcpu *vcpu,
@@ -2357,6 +2614,8 @@ static int kvm_vcpu_ioctl_x86_set_vcpu_events(struct kvm_vcpu *vcpu,
if (events->flags & KVM_VCPUEVENT_VALID_SIPI_VECTOR)
vcpu->arch.sipi_vector = events->sipi_vector;
+ kvm_make_request(KVM_REQ_EVENT, vcpu);
+
return 0;
}
@@ -2367,6 +2626,7 @@ static void kvm_vcpu_ioctl_x86_get_debugregs(struct kvm_vcpu *vcpu,
dbgregs->dr6 = vcpu->arch.dr6;
dbgregs->dr7 = vcpu->arch.dr7;
dbgregs->flags = 0;
+ memset(&dbgregs->reserved, 0, sizeof(dbgregs->reserved));
}
static int kvm_vcpu_ioctl_x86_set_debugregs(struct kvm_vcpu *vcpu,
@@ -2760,7 +3020,7 @@ static int kvm_vm_ioctl_set_nr_mmu_pages(struct kvm *kvm,
static int kvm_vm_ioctl_get_nr_mmu_pages(struct kvm *kvm)
{
- return kvm->arch.n_alloc_mmu_pages;
+ return kvm->arch.n_max_mmu_pages;
}
static int kvm_vm_ioctl_get_irqchip(struct kvm *kvm, struct kvm_irqchip *chip)
@@ -2796,18 +3056,18 @@ static int kvm_vm_ioctl_set_irqchip(struct kvm *kvm, struct kvm_irqchip *chip)
r = 0;
switch (chip->chip_id) {
case KVM_IRQCHIP_PIC_MASTER:
- raw_spin_lock(&pic_irqchip(kvm)->lock);
+ spin_lock(&pic_irqchip(kvm)->lock);
memcpy(&pic_irqchip(kvm)->pics[0],
&chip->chip.pic,
sizeof(struct kvm_pic_state));
- raw_spin_unlock(&pic_irqchip(kvm)->lock);
+ spin_unlock(&pic_irqchip(kvm)->lock);
break;
case KVM_IRQCHIP_PIC_SLAVE:
- raw_spin_lock(&pic_irqchip(kvm)->lock);
+ spin_lock(&pic_irqchip(kvm)->lock);
memcpy(&pic_irqchip(kvm)->pics[1],
&chip->chip.pic,
sizeof(struct kvm_pic_state));
- raw_spin_unlock(&pic_irqchip(kvm)->lock);
+ spin_unlock(&pic_irqchip(kvm)->lock);
break;
case KVM_IRQCHIP_IOAPIC:
r = kvm_set_ioapic(kvm, &chip->chip.ioapic);
@@ -2850,6 +3110,7 @@ static int kvm_vm_ioctl_get_pit2(struct kvm *kvm, struct kvm_pit_state2 *ps)
sizeof(ps->channels));
ps->flags = kvm->arch.vpit->pit_state.flags;
mutex_unlock(&kvm->arch.vpit->pit_state.lock);
+ memset(&ps->reserved, 0, sizeof(ps->reserved));
return r;
}
@@ -2913,10 +3174,6 @@ int kvm_vm_ioctl_get_dirty_log(struct kvm *kvm,
struct kvm_memslots *slots, *old_slots;
unsigned long *dirty_bitmap;
- spin_lock(&kvm->mmu_lock);
- kvm_mmu_slot_remove_write_access(kvm, log->slot);
- spin_unlock(&kvm->mmu_lock);
-
r = -ENOMEM;
dirty_bitmap = vmalloc(n);
if (!dirty_bitmap)
@@ -2938,6 +3195,10 @@ int kvm_vm_ioctl_get_dirty_log(struct kvm *kvm,
dirty_bitmap = old_slots->memslots[log->slot].dirty_bitmap;
kfree(old_slots);
+ spin_lock(&kvm->mmu_lock);
+ kvm_mmu_slot_remove_write_access(kvm, log->slot);
+ spin_unlock(&kvm->mmu_lock);
+
r = -EFAULT;
if (copy_to_user(log->dirty_bitmap, dirty_bitmap, n)) {
vfree(dirty_bitmap);
@@ -3201,7 +3462,6 @@ long kvm_arch_vm_ioctl(struct file *filp,
break;
}
case KVM_SET_CLOCK: {
- struct timespec now;
struct kvm_clock_data user_ns;
u64 now_ns;
s64 delta;
@@ -3215,21 +3475,23 @@ long kvm_arch_vm_ioctl(struct file *filp,
goto out;
r = 0;
- ktime_get_ts(&now);
- now_ns = timespec_to_ns(&now);
+ local_irq_disable();
+ now_ns = get_kernel_ns();
delta = user_ns.clock - now_ns;
+ local_irq_enable();
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);
+ local_irq_disable();
+ now_ns = get_kernel_ns();
user_ns.clock = kvm->arch.kvmclock_offset + now_ns;
+ local_irq_enable();
user_ns.flags = 0;
+ memset(&user_ns.pad, 0, sizeof(user_ns.pad));
r = -EFAULT;
if (copy_to_user(argp, &user_ns, sizeof(user_ns)))
@@ -3292,30 +3554,51 @@ void kvm_get_segment(struct kvm_vcpu *vcpu,
kvm_x86_ops->get_segment(vcpu, var, seg);
}
+static gpa_t translate_gpa(struct kvm_vcpu *vcpu, gpa_t gpa, u32 access)
+{
+ return gpa;
+}
+
+static gpa_t translate_nested_gpa(struct kvm_vcpu *vcpu, gpa_t gpa, u32 access)
+{
+ gpa_t t_gpa;
+ u32 error;
+
+ BUG_ON(!mmu_is_nested(vcpu));
+
+ /* NPT walks are always user-walks */
+ access |= PFERR_USER_MASK;
+ t_gpa = vcpu->arch.mmu.gva_to_gpa(vcpu, gpa, access, &error);
+ if (t_gpa == UNMAPPED_GVA)
+ vcpu->arch.fault.nested = true;
+
+ return t_gpa;
+}
+
gpa_t kvm_mmu_gva_to_gpa_read(struct kvm_vcpu *vcpu, gva_t gva, u32 *error)
{
u32 access = (kvm_x86_ops->get_cpl(vcpu) == 3) ? PFERR_USER_MASK : 0;
- return vcpu->arch.mmu.gva_to_gpa(vcpu, gva, access, error);
+ return vcpu->arch.walk_mmu->gva_to_gpa(vcpu, gva, access, error);
}
gpa_t kvm_mmu_gva_to_gpa_fetch(struct kvm_vcpu *vcpu, gva_t gva, u32 *error)
{
u32 access = (kvm_x86_ops->get_cpl(vcpu) == 3) ? PFERR_USER_MASK : 0;
access |= PFERR_FETCH_MASK;
- return vcpu->arch.mmu.gva_to_gpa(vcpu, gva, access, error);
+ return vcpu->arch.walk_mmu->gva_to_gpa(vcpu, gva, access, error);
}
gpa_t kvm_mmu_gva_to_gpa_write(struct kvm_vcpu *vcpu, gva_t gva, u32 *error)
{
u32 access = (kvm_x86_ops->get_cpl(vcpu) == 3) ? PFERR_USER_MASK : 0;
access |= PFERR_WRITE_MASK;
- return vcpu->arch.mmu.gva_to_gpa(vcpu, gva, access, error);
+ return vcpu->arch.walk_mmu->gva_to_gpa(vcpu, gva, access, error);
}
/* uses this to access any guest's mapped memory without checking CPL */
gpa_t kvm_mmu_gva_to_gpa_system(struct kvm_vcpu *vcpu, gva_t gva, u32 *error)
{
- return vcpu->arch.mmu.gva_to_gpa(vcpu, gva, 0, error);
+ return vcpu->arch.walk_mmu->gva_to_gpa(vcpu, gva, 0, error);
}
static int kvm_read_guest_virt_helper(gva_t addr, void *val, unsigned int bytes,
@@ -3326,7 +3609,8 @@ static int kvm_read_guest_virt_helper(gva_t addr, void *val, unsigned int bytes,
int r = X86EMUL_CONTINUE;
while (bytes) {
- gpa_t gpa = vcpu->arch.mmu.gva_to_gpa(vcpu, addr, access, error);
+ gpa_t gpa = vcpu->arch.walk_mmu->gva_to_gpa(vcpu, addr, access,
+ error);
unsigned offset = addr & (PAGE_SIZE-1);
unsigned toread = min(bytes, (unsigned)PAGE_SIZE - offset);
int ret;
@@ -3381,8 +3665,9 @@ static int kvm_write_guest_virt_system(gva_t addr, void *val,
int r = X86EMUL_CONTINUE;
while (bytes) {
- gpa_t gpa = vcpu->arch.mmu.gva_to_gpa(vcpu, addr,
- PFERR_WRITE_MASK, error);
+ gpa_t gpa = vcpu->arch.walk_mmu->gva_to_gpa(vcpu, addr,
+ PFERR_WRITE_MASK,
+ error);
unsigned offset = addr & (PAGE_SIZE-1);
unsigned towrite = min(bytes, (unsigned)PAGE_SIZE - offset);
int ret;
@@ -3624,7 +3909,7 @@ static int emulator_pio_in_emulated(int size, unsigned short port, void *val,
if (vcpu->arch.pio.count)
goto data_avail;
- trace_kvm_pio(1, port, size, 1);
+ trace_kvm_pio(0, port, size, 1);
vcpu->arch.pio.port = port;
vcpu->arch.pio.in = 1;
@@ -3652,7 +3937,7 @@ static int emulator_pio_out_emulated(int size, unsigned short port,
const void *val, unsigned int count,
struct kvm_vcpu *vcpu)
{
- trace_kvm_pio(0, port, size, 1);
+ trace_kvm_pio(1, port, size, 1);
vcpu->arch.pio.port = port;
vcpu->arch.pio.in = 0;
@@ -3693,8 +3978,10 @@ int kvm_emulate_wbinvd(struct kvm_vcpu *vcpu)
return X86EMUL_CONTINUE;
if (kvm_x86_ops->has_wbinvd_exit()) {
+ preempt_disable();
smp_call_function_many(vcpu->arch.wbinvd_dirty_mask,
wbinvd_ipi, NULL, 1);
+ preempt_enable();
cpumask_clear(vcpu->arch.wbinvd_dirty_mask);
}
wbinvd();
@@ -3791,6 +4078,11 @@ static void emulator_get_gdt(struct desc_ptr *dt, struct kvm_vcpu *vcpu)
kvm_x86_ops->get_gdt(vcpu, dt);
}
+static void emulator_get_idt(struct desc_ptr *dt, struct kvm_vcpu *vcpu)
+{
+ kvm_x86_ops->get_idt(vcpu, dt);
+}
+
static unsigned long emulator_get_cached_segment_base(int seg,
struct kvm_vcpu *vcpu)
{
@@ -3884,6 +4176,7 @@ static struct x86_emulate_ops emulate_ops = {
.set_segment_selector = emulator_set_segment_selector,
.get_cached_segment_base = emulator_get_cached_segment_base,
.get_gdt = emulator_get_gdt,
+ .get_idt = emulator_get_idt,
.get_cr = emulator_get_cr,
.set_cr = emulator_set_cr,
.cpl = emulator_get_cpl,
@@ -3919,13 +4212,64 @@ static void inject_emulated_exception(struct kvm_vcpu *vcpu)
{
struct x86_emulate_ctxt *ctxt = &vcpu->arch.emulate_ctxt;
if (ctxt->exception == PF_VECTOR)
- kvm_inject_page_fault(vcpu, ctxt->cr2, ctxt->error_code);
+ kvm_propagate_fault(vcpu);
else if (ctxt->error_code_valid)
kvm_queue_exception_e(vcpu, ctxt->exception, ctxt->error_code);
else
kvm_queue_exception(vcpu, ctxt->exception);
}
+static void init_emulate_ctxt(struct kvm_vcpu *vcpu)
+{
+ struct decode_cache *c = &vcpu->arch.emulate_ctxt.decode;
+ int cs_db, cs_l;
+
+ cache_all_regs(vcpu);
+
+ kvm_x86_ops->get_cs_db_l_bits(vcpu, &cs_db, &cs_l);
+
+ vcpu->arch.emulate_ctxt.vcpu = vcpu;
+ vcpu->arch.emulate_ctxt.eflags = kvm_x86_ops->get_rflags(vcpu);
+ vcpu->arch.emulate_ctxt.eip = kvm_rip_read(vcpu);
+ vcpu->arch.emulate_ctxt.mode =
+ (!is_protmode(vcpu)) ? X86EMUL_MODE_REAL :
+ (vcpu->arch.emulate_ctxt.eflags & X86_EFLAGS_VM)
+ ? X86EMUL_MODE_VM86 : cs_l
+ ? X86EMUL_MODE_PROT64 : cs_db
+ ? X86EMUL_MODE_PROT32 : X86EMUL_MODE_PROT16;
+ memset(c, 0, sizeof(struct decode_cache));
+ memcpy(c->regs, vcpu->arch.regs, sizeof c->regs);
+}
+
+int kvm_inject_realmode_interrupt(struct kvm_vcpu *vcpu, int irq)
+{
+ struct decode_cache *c = &vcpu->arch.emulate_ctxt.decode;
+ int ret;
+
+ init_emulate_ctxt(vcpu);
+
+ vcpu->arch.emulate_ctxt.decode.op_bytes = 2;
+ vcpu->arch.emulate_ctxt.decode.ad_bytes = 2;
+ vcpu->arch.emulate_ctxt.decode.eip = vcpu->arch.emulate_ctxt.eip;
+ ret = emulate_int_real(&vcpu->arch.emulate_ctxt, &emulate_ops, irq);
+
+ if (ret != X86EMUL_CONTINUE)
+ return EMULATE_FAIL;
+
+ vcpu->arch.emulate_ctxt.eip = c->eip;
+ memcpy(vcpu->arch.regs, c->regs, sizeof c->regs);
+ kvm_rip_write(vcpu, vcpu->arch.emulate_ctxt.eip);
+ kvm_x86_ops->set_rflags(vcpu, vcpu->arch.emulate_ctxt.eflags);
+
+ if (irq == NMI_VECTOR)
+ vcpu->arch.nmi_pending = false;
+ else
+ vcpu->arch.interrupt.pending = false;
+
+ return EMULATE_DONE;
+}
+EXPORT_SYMBOL_GPL(kvm_inject_realmode_interrupt);
+
static int handle_emulation_failure(struct kvm_vcpu *vcpu)
{
++vcpu->stat.insn_emulation_fail;
@@ -3982,24 +4326,15 @@ int emulate_instruction(struct kvm_vcpu *vcpu,
cache_all_regs(vcpu);
if (!(emulation_type & EMULTYPE_NO_DECODE)) {
- int cs_db, cs_l;
- kvm_x86_ops->get_cs_db_l_bits(vcpu, &cs_db, &cs_l);
-
- vcpu->arch.emulate_ctxt.vcpu = vcpu;
- vcpu->arch.emulate_ctxt.eflags = kvm_x86_ops->get_rflags(vcpu);
- vcpu->arch.emulate_ctxt.eip = kvm_rip_read(vcpu);
- vcpu->arch.emulate_ctxt.mode =
- (!is_protmode(vcpu)) ? X86EMUL_MODE_REAL :
- (vcpu->arch.emulate_ctxt.eflags & X86_EFLAGS_VM)
- ? X86EMUL_MODE_VM86 : cs_l
- ? X86EMUL_MODE_PROT64 : cs_db
- ? X86EMUL_MODE_PROT32 : X86EMUL_MODE_PROT16;
- memset(c, 0, sizeof(struct decode_cache));
- memcpy(c->regs, vcpu->arch.regs, sizeof c->regs);
+ init_emulate_ctxt(vcpu);
vcpu->arch.emulate_ctxt.interruptibility = 0;
vcpu->arch.emulate_ctxt.exception = -1;
+ vcpu->arch.emulate_ctxt.perm_ok = false;
+
+ r = x86_decode_insn(&vcpu->arch.emulate_ctxt);
+ if (r == X86EMUL_PROPAGATE_FAULT)
+ goto done;
- r = x86_decode_insn(&vcpu->arch.emulate_ctxt, &emulate_ops);
trace_kvm_emulate_insn_start(vcpu);
/* Only allow emulation of specific instructions on #UD
@@ -4049,41 +4384,39 @@ int emulate_instruction(struct kvm_vcpu *vcpu,
memcpy(c->regs, vcpu->arch.regs, sizeof c->regs);
restart:
- r = x86_emulate_insn(&vcpu->arch.emulate_ctxt, &emulate_ops);
+ r = x86_emulate_insn(&vcpu->arch.emulate_ctxt);
- if (r) { /* emulation failed */
+ if (r == EMULATION_FAILED) {
if (reexecute_instruction(vcpu, cr2))
return EMULATE_DONE;
return handle_emulation_failure(vcpu);
}
- toggle_interruptibility(vcpu, vcpu->arch.emulate_ctxt.interruptibility);
- kvm_x86_ops->set_rflags(vcpu, vcpu->arch.emulate_ctxt.eflags);
- memcpy(vcpu->arch.regs, c->regs, sizeof c->regs);
- kvm_rip_write(vcpu, vcpu->arch.emulate_ctxt.eip);
-
+done:
if (vcpu->arch.emulate_ctxt.exception >= 0) {
inject_emulated_exception(vcpu);
- return EMULATE_DONE;
- }
-
- if (vcpu->arch.pio.count) {
+ r = EMULATE_DONE;
+ } else if (vcpu->arch.pio.count) {
if (!vcpu->arch.pio.in)
vcpu->arch.pio.count = 0;
- return EMULATE_DO_MMIO;
- }
-
- if (vcpu->mmio_needed) {
+ r = EMULATE_DO_MMIO;
+ } else if (vcpu->mmio_needed) {
if (vcpu->mmio_is_write)
vcpu->mmio_needed = 0;
- return EMULATE_DO_MMIO;
- }
-
- if (vcpu->arch.emulate_ctxt.restart)
+ r = EMULATE_DO_MMIO;
+ } else if (r == EMULATION_RESTART)
goto restart;
+ else
+ r = EMULATE_DONE;
- return EMULATE_DONE;
+ toggle_interruptibility(vcpu, vcpu->arch.emulate_ctxt.interruptibility);
+ kvm_x86_ops->set_rflags(vcpu, vcpu->arch.emulate_ctxt.eflags);
+ kvm_make_request(KVM_REQ_EVENT, vcpu);
+ memcpy(vcpu->arch.regs, c->regs, sizeof c->regs);
+ kvm_rip_write(vcpu, vcpu->arch.emulate_ctxt.eip);
+
+ return r;
}
EXPORT_SYMBOL_GPL(emulate_instruction);
@@ -4097,9 +4430,23 @@ int kvm_fast_pio_out(struct kvm_vcpu *vcpu, int size, unsigned short port)
}
EXPORT_SYMBOL_GPL(kvm_fast_pio_out);
-static void bounce_off(void *info)
+static void tsc_bad(void *info)
{
- /* nothing */
+ __get_cpu_var(cpu_tsc_khz) = 0;
+}
+
+static void tsc_khz_changed(void *data)
+{
+ struct cpufreq_freqs *freq = data;
+ unsigned long khz = 0;
+
+ if (data)
+ khz = freq->new;
+ else if (!boot_cpu_has(X86_FEATURE_CONSTANT_TSC))
+ khz = cpufreq_quick_get(raw_smp_processor_id());
+ if (!khz)
+ khz = tsc_khz;
+ __get_cpu_var(cpu_tsc_khz) = khz;
}
static int kvmclock_cpufreq_notifier(struct notifier_block *nb, unsigned long val,
@@ -4110,21 +4457,60 @@ static int kvmclock_cpufreq_notifier(struct notifier_block *nb, unsigned long va
struct kvm_vcpu *vcpu;
int i, send_ipi = 0;
+ /*
+ * We allow guests to temporarily run on slowing clocks,
+ * provided we notify them after, or to run on accelerating
+ * clocks, provided we notify them before. Thus time never
+ * goes backwards.
+ *
+ * However, we have a problem. We can't atomically update
+ * the frequency of a given CPU from this function; it is
+ * merely a notifier, which can be called from any CPU.
+ * Changing the TSC frequency at arbitrary points in time
+ * requires a recomputation of local variables related to
+ * the TSC for each VCPU. We must flag these local variables
+ * to be updated and be sure the update takes place with the
+ * new frequency before any guests proceed.
+ *
+ * Unfortunately, the combination of hotplug CPU and frequency
+ * change creates an intractable locking scenario; the order
+ * of when these callouts happen is undefined with respect to
+ * CPU hotplug, and they can race with each other. As such,
+ * merely setting per_cpu(cpu_tsc_khz) = X during a hotadd is
+ * undefined; you can actually have a CPU frequency change take
+ * place in between the computation of X and the setting of the
+ * variable. To protect against this problem, all updates of
+ * the per_cpu tsc_khz variable are done in an interrupt
+ * protected IPI, and all callers wishing to update the value
+ * must wait for a synchronous IPI to complete (which is trivial
+ * if the caller is on the CPU already). This establishes the
+ * necessary total order on variable updates.
+ *
+ * Note that because a guest time update may take place
+ * anytime after the setting of the VCPU's request bit, the
+ * correct TSC value must be set before the request. However,
+ * to ensure the update actually makes it to any guest which
+ * starts running in hardware virtualization between the set
+ * and the acquisition of the spinlock, we must also ping the
+ * CPU after setting the request bit.
+ *
+ */
+
if (val == CPUFREQ_PRECHANGE && freq->old > freq->new)
return 0;
if (val == CPUFREQ_POSTCHANGE && freq->old < freq->new)
return 0;
- per_cpu(cpu_tsc_khz, freq->cpu) = freq->new;
+
+ smp_call_function_single(freq->cpu, tsc_khz_changed, freq, 1);
spin_lock(&kvm_lock);
list_for_each_entry(kvm, &vm_list, vm_list) {
kvm_for_each_vcpu(i, vcpu, kvm) {
if (vcpu->cpu != freq->cpu)
continue;
- if (!kvm_request_guest_time_update(vcpu))
- continue;
+ kvm_make_request(KVM_REQ_CLOCK_UPDATE, vcpu);
if (vcpu->cpu != smp_processor_id())
- send_ipi++;
+ send_ipi = 1;
}
}
spin_unlock(&kvm_lock);
@@ -4142,32 +4528,57 @@ static int kvmclock_cpufreq_notifier(struct notifier_block *nb, unsigned long va
* guest context is entered kvmclock will be updated,
* so the guest will not see stale values.
*/
- smp_call_function_single(freq->cpu, bounce_off, NULL, 1);
+ smp_call_function_single(freq->cpu, tsc_khz_changed, freq, 1);
}
return 0;
}
static struct notifier_block kvmclock_cpufreq_notifier_block = {
- .notifier_call = kvmclock_cpufreq_notifier
+ .notifier_call = kvmclock_cpufreq_notifier
+};
+
+static int kvmclock_cpu_notifier(struct notifier_block *nfb,
+ unsigned long action, void *hcpu)
+{
+ unsigned int cpu = (unsigned long)hcpu;
+
+ switch (action) {
+ case CPU_ONLINE:
+ case CPU_DOWN_FAILED:
+ smp_call_function_single(cpu, tsc_khz_changed, NULL, 1);
+ break;
+ case CPU_DOWN_PREPARE:
+ smp_call_function_single(cpu, tsc_bad, NULL, 1);
+ break;
+ }
+ return NOTIFY_OK;
+}
+
+static struct notifier_block kvmclock_cpu_notifier_block = {
+ .notifier_call = kvmclock_cpu_notifier,
+ .priority = -INT_MAX
};
static void kvm_timer_init(void)
{
int cpu;
+ max_tsc_khz = tsc_khz;
+ register_hotcpu_notifier(&kvmclock_cpu_notifier_block);
if (!boot_cpu_has(X86_FEATURE_CONSTANT_TSC)) {
+#ifdef CONFIG_CPU_FREQ
+ struct cpufreq_policy policy;
+ memset(&policy, 0, sizeof(policy));
+ cpufreq_get_policy(&policy, get_cpu());
+ if (policy.cpuinfo.max_freq)
+ max_tsc_khz = policy.cpuinfo.max_freq;
+#endif
cpufreq_register_notifier(&kvmclock_cpufreq_notifier_block,
CPUFREQ_TRANSITION_NOTIFIER);
- 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;
}
+ pr_debug("kvm: max_tsc_khz = %ld\n", max_tsc_khz);
+ for_each_online_cpu(cpu)
+ smp_call_function_single(cpu, tsc_khz_changed, NULL, 1);
}
static DEFINE_PER_CPU(struct kvm_vcpu *, current_vcpu);
@@ -4269,6 +4680,7 @@ void kvm_arch_exit(void)
if (!boot_cpu_has(X86_FEATURE_CONSTANT_TSC))
cpufreq_unregister_notifier(&kvmclock_cpufreq_notifier_block,
CPUFREQ_TRANSITION_NOTIFIER);
+ unregister_hotcpu_notifier(&kvmclock_cpu_notifier_block);
kvm_x86_ops = NULL;
kvm_mmu_module_exit();
}
@@ -4684,8 +5096,11 @@ static int vcpu_enter_guest(struct kvm_vcpu *vcpu)
kvm_mmu_unload(vcpu);
if (kvm_check_request(KVM_REQ_MIGRATE_TIMER, vcpu))
__kvm_migrate_timers(vcpu);
- if (kvm_check_request(KVM_REQ_KVMCLOCK_UPDATE, vcpu))
- kvm_write_guest_time(vcpu);
+ if (kvm_check_request(KVM_REQ_CLOCK_UPDATE, vcpu)) {
+ r = kvm_guest_time_update(vcpu);
+ if (unlikely(r))
+ goto out;
+ }
if (kvm_check_request(KVM_REQ_MMU_SYNC, vcpu))
kvm_mmu_sync_roots(vcpu);
if (kvm_check_request(KVM_REQ_TLB_FLUSH, vcpu))
@@ -4710,6 +5125,21 @@ static int vcpu_enter_guest(struct kvm_vcpu *vcpu)
if (unlikely(r))
goto out;
+ if (kvm_check_request(KVM_REQ_EVENT, vcpu) || req_int_win) {
+ inject_pending_event(vcpu);
+
+ /* enable NMI/IRQ window open exits if needed */
+ if (vcpu->arch.nmi_pending)
+ kvm_x86_ops->enable_nmi_window(vcpu);
+ else if (kvm_cpu_has_interrupt(vcpu) || req_int_win)
+ kvm_x86_ops->enable_irq_window(vcpu);
+
+ if (kvm_lapic_enabled(vcpu)) {
+ update_cr8_intercept(vcpu);
+ kvm_lapic_sync_to_vapic(vcpu);
+ }
+ }
+
preempt_disable();
kvm_x86_ops->prepare_guest_switch(vcpu);
@@ -4728,23 +5158,11 @@ static int vcpu_enter_guest(struct kvm_vcpu *vcpu)
smp_wmb();
local_irq_enable();
preempt_enable();
+ kvm_x86_ops->cancel_injection(vcpu);
r = 1;
goto out;
}
- inject_pending_event(vcpu);
-
- /* enable NMI/IRQ window open exits if needed */
- if (vcpu->arch.nmi_pending)
- kvm_x86_ops->enable_nmi_window(vcpu);
- else if (kvm_cpu_has_interrupt(vcpu) || req_int_win)
- kvm_x86_ops->enable_irq_window(vcpu);
-
- if (kvm_lapic_enabled(vcpu)) {
- update_cr8_intercept(vcpu);
- kvm_lapic_sync_to_vapic(vcpu);
- }
-
srcu_read_unlock(&vcpu->kvm->srcu, vcpu->srcu_idx);
kvm_guest_enter();
@@ -4770,6 +5188,8 @@ static int vcpu_enter_guest(struct kvm_vcpu *vcpu)
if (hw_breakpoint_active())
hw_breakpoint_restore();
+ kvm_get_msr(vcpu, MSR_IA32_TSC, &vcpu->arch.last_guest_tsc);
+
atomic_set(&vcpu->guest_mode, 0);
smp_wmb();
local_irq_enable();
@@ -4899,8 +5319,7 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run)
if (!irqchip_in_kernel(vcpu->kvm))
kvm_set_cr8(vcpu, kvm_run->cr8);
- if (vcpu->arch.pio.count || vcpu->mmio_needed ||
- vcpu->arch.emulate_ctxt.restart) {
+ if (vcpu->arch.pio.count || vcpu->mmio_needed) {
if (vcpu->mmio_needed) {
memcpy(vcpu->mmio_data, kvm_run->mmio.data, 8);
vcpu->mmio_read_completed = 1;
@@ -4981,6 +5400,8 @@ int kvm_arch_vcpu_ioctl_set_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
vcpu->arch.exception.pending = false;
+ kvm_make_request(KVM_REQ_EVENT, vcpu);
+
return 0;
}
@@ -5044,6 +5465,7 @@ int kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu *vcpu,
struct kvm_mp_state *mp_state)
{
vcpu->arch.mp_state = mp_state->mp_state;
+ kvm_make_request(KVM_REQ_EVENT, vcpu);
return 0;
}
@@ -5051,24 +5473,11 @@ int kvm_task_switch(struct kvm_vcpu *vcpu, u16 tss_selector, int reason,
bool has_error_code, u32 error_code)
{
struct decode_cache *c = &vcpu->arch.emulate_ctxt.decode;
- int cs_db, cs_l, ret;
- cache_all_regs(vcpu);
+ int ret;
- kvm_x86_ops->get_cs_db_l_bits(vcpu, &cs_db, &cs_l);
+ init_emulate_ctxt(vcpu);
- vcpu->arch.emulate_ctxt.vcpu = vcpu;
- vcpu->arch.emulate_ctxt.eflags = kvm_x86_ops->get_rflags(vcpu);
- vcpu->arch.emulate_ctxt.eip = kvm_rip_read(vcpu);
- vcpu->arch.emulate_ctxt.mode =
- (!is_protmode(vcpu)) ? X86EMUL_MODE_REAL :
- (vcpu->arch.emulate_ctxt.eflags & X86_EFLAGS_VM)
- ? X86EMUL_MODE_VM86 : cs_l
- ? X86EMUL_MODE_PROT64 : cs_db
- ? X86EMUL_MODE_PROT32 : X86EMUL_MODE_PROT16;
- memset(c, 0, sizeof(struct decode_cache));
- memcpy(c->regs, vcpu->arch.regs, sizeof c->regs);
-
- ret = emulator_task_switch(&vcpu->arch.emulate_ctxt, &emulate_ops,
+ ret = emulator_task_switch(&vcpu->arch.emulate_ctxt,
tss_selector, reason, has_error_code,
error_code);
@@ -5078,6 +5487,7 @@ int kvm_task_switch(struct kvm_vcpu *vcpu, u16 tss_selector, int reason,
memcpy(vcpu->arch.regs, c->regs, sizeof c->regs);
kvm_rip_write(vcpu, vcpu->arch.emulate_ctxt.eip);
kvm_x86_ops->set_rflags(vcpu, vcpu->arch.emulate_ctxt.eflags);
+ kvm_make_request(KVM_REQ_EVENT, vcpu);
return EMULATE_DONE;
}
EXPORT_SYMBOL_GPL(kvm_task_switch);
@@ -5113,7 +5523,7 @@ int kvm_arch_vcpu_ioctl_set_sregs(struct kvm_vcpu *vcpu,
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)) {
- load_pdptrs(vcpu, vcpu->arch.cr3);
+ load_pdptrs(vcpu, vcpu->arch.walk_mmu, vcpu->arch.cr3);
mmu_reset_needed = 1;
}
@@ -5148,6 +5558,8 @@ int kvm_arch_vcpu_ioctl_set_sregs(struct kvm_vcpu *vcpu,
!is_protmode(vcpu))
vcpu->arch.mp_state = KVM_MP_STATE_RUNNABLE;
+ kvm_make_request(KVM_REQ_EVENT, vcpu);
+
return 0;
}
@@ -5334,6 +5746,10 @@ void kvm_arch_vcpu_free(struct kvm_vcpu *vcpu)
struct kvm_vcpu *kvm_arch_vcpu_create(struct kvm *kvm,
unsigned int id)
{
+ if (check_tsc_unstable() && atomic_read(&kvm->online_vcpus) != 0)
+ printk_once(KERN_WARNING
+ "kvm: SMP vm created on host with unstable TSC; "
+ "guest TSC will not be reliable\n");
return kvm_x86_ops->vcpu_create(kvm, id);
}
@@ -5376,22 +5792,22 @@ int kvm_arch_vcpu_reset(struct kvm_vcpu *vcpu)
vcpu->arch.dr6 = DR6_FIXED_1;
vcpu->arch.dr7 = DR7_FIXED_1;
+ kvm_make_request(KVM_REQ_EVENT, vcpu);
+
return kvm_x86_ops->vcpu_reset(vcpu);
}
int kvm_arch_hardware_enable(void *garbage)
{
- /*
- * Since this may be called from a hotplug notifcation,
- * we can't get the CPU frequency directly.
- */
- if (!boot_cpu_has(X86_FEATURE_CONSTANT_TSC)) {
- int cpu = raw_smp_processor_id();
- per_cpu(cpu_tsc_khz, cpu) = 0;
- }
+ struct kvm *kvm;
+ struct kvm_vcpu *vcpu;
+ int i;
kvm_shared_msr_cpu_online();
-
+ list_for_each_entry(kvm, &vm_list, vm_list)
+ kvm_for_each_vcpu(i, vcpu, kvm)
+ if (vcpu->cpu == smp_processor_id())
+ kvm_make_request(KVM_REQ_CLOCK_UPDATE, vcpu);
return kvm_x86_ops->hardware_enable(garbage);
}
@@ -5425,7 +5841,11 @@ int kvm_arch_vcpu_init(struct kvm_vcpu *vcpu)
BUG_ON(vcpu->kvm == NULL);
kvm = vcpu->kvm;
+ vcpu->arch.emulate_ctxt.ops = &emulate_ops;
+ vcpu->arch.walk_mmu = &vcpu->arch.mmu;
vcpu->arch.mmu.root_hpa = INVALID_PAGE;
+ vcpu->arch.mmu.translate_gpa = translate_gpa;
+ vcpu->arch.nested_mmu.translate_gpa = translate_nested_gpa;
if (!irqchip_in_kernel(kvm) || kvm_vcpu_is_bsp(vcpu))
vcpu->arch.mp_state = KVM_MP_STATE_RUNNABLE;
else
@@ -5438,6 +5858,9 @@ int kvm_arch_vcpu_init(struct kvm_vcpu *vcpu)
}
vcpu->arch.pio_data = page_address(page);
+ if (!kvm->arch.virtual_tsc_khz)
+ kvm_arch_set_tsc_khz(kvm, max_tsc_khz);
+
r = kvm_mmu_create(vcpu);
if (r < 0)
goto fail_free_pio_data;
@@ -5497,7 +5920,7 @@ struct kvm *kvm_arch_create_vm(void)
/* Reserve bit 0 of irq_sources_bitmap for userspace irq source */
set_bit(KVM_USERSPACE_IRQ_SOURCE_ID, &kvm->arch.irq_sources_bitmap);
- rdtscll(kvm->arch.vm_init_tsc);
+ spin_lock_init(&kvm->arch.tsc_write_lock);
return kvm;
}
@@ -5684,6 +6107,7 @@ void kvm_set_rflags(struct kvm_vcpu *vcpu, unsigned long rflags)
kvm_is_linear_rip(vcpu, vcpu->arch.singlestep_rip))
rflags |= X86_EFLAGS_TF;
kvm_x86_ops->set_rflags(vcpu, rflags);
+ kvm_make_request(KVM_REQ_EVENT, vcpu);
}
EXPORT_SYMBOL_GPL(kvm_set_rflags);