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authorLinus Torvalds <torvalds@linux-foundation.org>2016-11-19 13:31:40 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2016-11-19 13:31:40 -0800
commitdce9ce3615ca03bd7adb09a182b5ee192684f17f (patch)
tree6b7334ec86ac89448f97cea7fb6523ceb6730129
parentf6918382c7d8a13eb1c71d375bdd88f3ae6a5833 (diff)
parenta2b07739ff5ded8ca7e9c7ff0749ed6f0d36aee2 (diff)
downloadlinux-stericsson-dce9ce3615ca03bd7adb09a182b5ee192684f17f.tar.gz
Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull KVM fixes from Radim Krčmář: "ARM: - Fix handling of the 32bit cycle counter - Fix cycle counter filtering x86: - Fix a race leading to double unregistering of user notifiers - Amend oversight in kvm_arch_set_irq that turned Hyper-V code dead - Use SRCU around kvm_lapic_set_vapic_addr - Avoid recursive flushing of asynchronous page faults - Do not rely on deferred update in KVM_GET_CLOCK, which fixes #GP - Let userspace know that KVM_GET_CLOCK is useful with master clock; 4.9 changed the return value to better match the guest clock, but didn't provide means to let guests take advantage of it" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: kvm: x86: merge kvm_arch_set_irq and kvm_arch_set_irq_inatomic KVM: x86: fix missed SRCU usage in kvm_lapic_set_vapic_addr KVM: async_pf: avoid recursive flushing of work items kvm: kvmclock: let KVM_GET_CLOCK return whether the master clock is in use KVM: Disable irq while unregistering user notifier KVM: x86: do not go through vcpu in __get_kvmclock_ns KVM: arm64: Fix the issues when guest PMCCFILTR is configured arm64: KVM: pmu: Fix AArch32 cycle counter access
-rw-r--r--Documentation/virtual/kvm/api.txt11
-rw-r--r--arch/arm64/include/asm/perf_event.h10
-rw-r--r--arch/arm64/kernel/perf_event.c10
-rw-r--r--arch/arm64/kvm/sys_regs.c10
-rw-r--r--arch/x86/kvm/irq_comm.c58
-rw-r--r--arch/x86/kvm/x86.c47
-rw-r--r--include/uapi/linux/kvm.h7
-rw-r--r--virt/kvm/arm/pmu.c8
-rw-r--r--virt/kvm/async_pf.c13
9 files changed, 114 insertions, 60 deletions
diff --git a/Documentation/virtual/kvm/api.txt b/Documentation/virtual/kvm/api.txt
index 739db9ab16b2..6bbceb9a3a19 100644
--- a/Documentation/virtual/kvm/api.txt
+++ b/Documentation/virtual/kvm/api.txt
@@ -777,6 +777,17 @@ Gets the current timestamp of kvmclock as seen by the current guest. In
conjunction with KVM_SET_CLOCK, it is used to ensure monotonicity on scenarios
such as migration.
+When KVM_CAP_ADJUST_CLOCK is passed to KVM_CHECK_EXTENSION, it returns the
+set of bits that KVM can return in struct kvm_clock_data's flag member.
+
+The only flag defined now is KVM_CLOCK_TSC_STABLE. If set, the returned
+value is the exact kvmclock value seen by all VCPUs at the instant
+when KVM_GET_CLOCK was called. If clear, the returned value is simply
+CLOCK_MONOTONIC plus a constant offset; the offset can be modified
+with KVM_SET_CLOCK. KVM will try to make all VCPUs follow this clock,
+but the exact value read by each VCPU could differ, because the host
+TSC is not stable.
+
struct kvm_clock_data {
__u64 clock; /* kvmclock current value */
__u32 flags;
diff --git a/arch/arm64/include/asm/perf_event.h b/arch/arm64/include/asm/perf_event.h
index 2065f46fa740..38b6a2b49d68 100644
--- a/arch/arm64/include/asm/perf_event.h
+++ b/arch/arm64/include/asm/perf_event.h
@@ -46,7 +46,15 @@
#define ARMV8_PMU_EVTYPE_MASK 0xc800ffff /* Mask for writable bits */
#define ARMV8_PMU_EVTYPE_EVENT 0xffff /* Mask for EVENT bits */
-#define ARMV8_PMU_EVTYPE_EVENT_SW_INCR 0 /* Software increment event */
+/*
+ * PMUv3 event types: required events
+ */
+#define ARMV8_PMUV3_PERFCTR_SW_INCR 0x00
+#define ARMV8_PMUV3_PERFCTR_L1D_CACHE_REFILL 0x03
+#define ARMV8_PMUV3_PERFCTR_L1D_CACHE 0x04
+#define ARMV8_PMUV3_PERFCTR_BR_MIS_PRED 0x10
+#define ARMV8_PMUV3_PERFCTR_CPU_CYCLES 0x11
+#define ARMV8_PMUV3_PERFCTR_BR_PRED 0x12
/*
* Event filters for PMUv3
diff --git a/arch/arm64/kernel/perf_event.c b/arch/arm64/kernel/perf_event.c
index a9310a69fffd..57ae9d9ed9bb 100644
--- a/arch/arm64/kernel/perf_event.c
+++ b/arch/arm64/kernel/perf_event.c
@@ -31,17 +31,9 @@
/*
* ARMv8 PMUv3 Performance Events handling code.
- * Common event types.
+ * Common event types (some are defined in asm/perf_event.h).
*/
-/* Required events. */
-#define ARMV8_PMUV3_PERFCTR_SW_INCR 0x00
-#define ARMV8_PMUV3_PERFCTR_L1D_CACHE_REFILL 0x03
-#define ARMV8_PMUV3_PERFCTR_L1D_CACHE 0x04
-#define ARMV8_PMUV3_PERFCTR_BR_MIS_PRED 0x10
-#define ARMV8_PMUV3_PERFCTR_CPU_CYCLES 0x11
-#define ARMV8_PMUV3_PERFCTR_BR_PRED 0x12
-
/* At least one of the following is required. */
#define ARMV8_PMUV3_PERFCTR_INST_RETIRED 0x08
#define ARMV8_PMUV3_PERFCTR_INST_SPEC 0x1B
diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c
index f302fdb3a030..87e7e6608cd8 100644
--- a/arch/arm64/kvm/sys_regs.c
+++ b/arch/arm64/kvm/sys_regs.c
@@ -597,8 +597,14 @@ static bool access_pmu_evcntr(struct kvm_vcpu *vcpu,
idx = ARMV8_PMU_CYCLE_IDX;
} else {
- BUG();
+ return false;
}
+ } else if (r->CRn == 0 && r->CRm == 9) {
+ /* PMCCNTR */
+ if (pmu_access_event_counter_el0_disabled(vcpu))
+ return false;
+
+ idx = ARMV8_PMU_CYCLE_IDX;
} else if (r->CRn == 14 && (r->CRm & 12) == 8) {
/* PMEVCNTRn_EL0 */
if (pmu_access_event_counter_el0_disabled(vcpu))
@@ -606,7 +612,7 @@ static bool access_pmu_evcntr(struct kvm_vcpu *vcpu,
idx = ((r->CRm & 3) << 3) | (r->Op2 & 7);
} else {
- BUG();
+ return false;
}
if (!pmu_counter_idx_valid(vcpu, idx))
diff --git a/arch/x86/kvm/irq_comm.c b/arch/x86/kvm/irq_comm.c
index 25810b144b58..4da03030d5a7 100644
--- a/arch/x86/kvm/irq_comm.c
+++ b/arch/x86/kvm/irq_comm.c
@@ -156,6 +156,16 @@ int kvm_set_msi(struct kvm_kernel_irq_routing_entry *e,
}
+static int kvm_hv_set_sint(struct kvm_kernel_irq_routing_entry *e,
+ struct kvm *kvm, int irq_source_id, int level,
+ bool line_status)
+{
+ if (!level)
+ return -1;
+
+ return kvm_hv_synic_set_irq(kvm, e->hv_sint.vcpu, e->hv_sint.sint);
+}
+
int kvm_arch_set_irq_inatomic(struct kvm_kernel_irq_routing_entry *e,
struct kvm *kvm, int irq_source_id, int level,
bool line_status)
@@ -163,18 +173,26 @@ int kvm_arch_set_irq_inatomic(struct kvm_kernel_irq_routing_entry *e,
struct kvm_lapic_irq irq;
int r;
- if (unlikely(e->type != KVM_IRQ_ROUTING_MSI))
- return -EWOULDBLOCK;
+ switch (e->type) {
+ case KVM_IRQ_ROUTING_HV_SINT:
+ return kvm_hv_set_sint(e, kvm, irq_source_id, level,
+ line_status);
- if (kvm_msi_route_invalid(kvm, e))
- return -EINVAL;
+ case KVM_IRQ_ROUTING_MSI:
+ if (kvm_msi_route_invalid(kvm, e))
+ return -EINVAL;
- kvm_set_msi_irq(kvm, e, &irq);
+ kvm_set_msi_irq(kvm, e, &irq);
- if (kvm_irq_delivery_to_apic_fast(kvm, NULL, &irq, &r, NULL))
- return r;
- else
- return -EWOULDBLOCK;
+ if (kvm_irq_delivery_to_apic_fast(kvm, NULL, &irq, &r, NULL))
+ return r;
+ break;
+
+ default:
+ break;
+ }
+
+ return -EWOULDBLOCK;
}
int kvm_request_irq_source_id(struct kvm *kvm)
@@ -254,16 +272,6 @@ void kvm_fire_mask_notifiers(struct kvm *kvm, unsigned irqchip, unsigned pin,
srcu_read_unlock(&kvm->irq_srcu, idx);
}
-static int kvm_hv_set_sint(struct kvm_kernel_irq_routing_entry *e,
- struct kvm *kvm, int irq_source_id, int level,
- bool line_status)
-{
- if (!level)
- return -1;
-
- return kvm_hv_synic_set_irq(kvm, e->hv_sint.vcpu, e->hv_sint.sint);
-}
-
int kvm_set_routing_entry(struct kvm *kvm,
struct kvm_kernel_irq_routing_entry *e,
const struct kvm_irq_routing_entry *ue)
@@ -423,18 +431,6 @@ void kvm_scan_ioapic_routes(struct kvm_vcpu *vcpu,
srcu_read_unlock(&kvm->irq_srcu, idx);
}
-int kvm_arch_set_irq(struct kvm_kernel_irq_routing_entry *irq, struct kvm *kvm,
- int irq_source_id, int level, bool line_status)
-{
- switch (irq->type) {
- case KVM_IRQ_ROUTING_HV_SINT:
- return kvm_hv_set_sint(irq, kvm, irq_source_id, level,
- line_status);
- default:
- return -EWOULDBLOCK;
- }
-}
-
void kvm_arch_irq_routing_update(struct kvm *kvm)
{
kvm_hv_irq_routing_update(kvm);
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 3017de0431bd..04c5d96b1d67 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -210,7 +210,18 @@ static void kvm_on_user_return(struct user_return_notifier *urn)
struct kvm_shared_msrs *locals
= container_of(urn, struct kvm_shared_msrs, urn);
struct kvm_shared_msr_values *values;
+ unsigned long flags;
+ /*
+ * Disabling irqs at this point since the following code could be
+ * interrupted and executed through kvm_arch_hardware_disable()
+ */
+ local_irq_save(flags);
+ if (locals->registered) {
+ locals->registered = false;
+ user_return_notifier_unregister(urn);
+ }
+ local_irq_restore(flags);
for (slot = 0; slot < shared_msrs_global.nr; ++slot) {
values = &locals->values[slot];
if (values->host != values->curr) {
@@ -218,8 +229,6 @@ static void kvm_on_user_return(struct user_return_notifier *urn)
values->curr = values->host;
}
}
- locals->registered = false;
- user_return_notifier_unregister(urn);
}
static void shared_msr_update(unsigned slot, u32 msr)
@@ -1724,18 +1733,23 @@ static void kvm_gen_update_masterclock(struct kvm *kvm)
static u64 __get_kvmclock_ns(struct kvm *kvm)
{
- struct kvm_vcpu *vcpu = kvm_get_vcpu(kvm, 0);
struct kvm_arch *ka = &kvm->arch;
- s64 ns;
+ struct pvclock_vcpu_time_info hv_clock;
- if (vcpu->arch.hv_clock.flags & PVCLOCK_TSC_STABLE_BIT) {
- u64 tsc = kvm_read_l1_tsc(vcpu, rdtsc());
- ns = __pvclock_read_cycles(&vcpu->arch.hv_clock, tsc);
- } else {
- ns = ktime_get_boot_ns() + ka->kvmclock_offset;
+ spin_lock(&ka->pvclock_gtod_sync_lock);
+ if (!ka->use_master_clock) {
+ spin_unlock(&ka->pvclock_gtod_sync_lock);
+ return ktime_get_boot_ns() + ka->kvmclock_offset;
}
- return ns;
+ hv_clock.tsc_timestamp = ka->master_cycle_now;
+ hv_clock.system_time = ka->master_kernel_ns + ka->kvmclock_offset;
+ spin_unlock(&ka->pvclock_gtod_sync_lock);
+
+ kvm_get_time_scale(NSEC_PER_SEC, __this_cpu_read(cpu_tsc_khz) * 1000LL,
+ &hv_clock.tsc_shift,
+ &hv_clock.tsc_to_system_mul);
+ return __pvclock_read_cycles(&hv_clock, rdtsc());
}
u64 get_kvmclock_ns(struct kvm *kvm)
@@ -2596,7 +2610,6 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
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:
case KVM_CAP_HYPERV:
case KVM_CAP_HYPERV_VAPIC:
@@ -2623,6 +2636,9 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
#endif
r = 1;
break;
+ case KVM_CAP_ADJUST_CLOCK:
+ r = KVM_CLOCK_TSC_STABLE;
+ break;
case KVM_CAP_X86_SMM:
/* SMBASE is usually relocated above 1M on modern chipsets,
* and SMM handlers might indeed rely on 4G segment limits,
@@ -3415,6 +3431,7 @@ long kvm_arch_vcpu_ioctl(struct file *filp,
};
case KVM_SET_VAPIC_ADDR: {
struct kvm_vapic_addr va;
+ int idx;
r = -EINVAL;
if (!lapic_in_kernel(vcpu))
@@ -3422,7 +3439,9 @@ long kvm_arch_vcpu_ioctl(struct file *filp,
r = -EFAULT;
if (copy_from_user(&va, argp, sizeof va))
goto out;
+ idx = srcu_read_lock(&vcpu->kvm->srcu);
r = kvm_lapic_set_vapic_addr(vcpu, va.vapic_addr);
+ srcu_read_unlock(&vcpu->kvm->srcu, idx);
break;
}
case KVM_X86_SETUP_MCE: {
@@ -4103,9 +4122,11 @@ long kvm_arch_vm_ioctl(struct file *filp,
struct kvm_clock_data user_ns;
u64 now_ns;
- now_ns = get_kvmclock_ns(kvm);
+ local_irq_disable();
+ now_ns = __get_kvmclock_ns(kvm);
user_ns.clock = now_ns;
- user_ns.flags = 0;
+ user_ns.flags = kvm->arch.use_master_clock ? KVM_CLOCK_TSC_STABLE : 0;
+ local_irq_enable();
memset(&user_ns.pad, 0, sizeof(user_ns.pad));
r = -EFAULT;
diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h
index 300ef255d1e0..4ee67cb99143 100644
--- a/include/uapi/linux/kvm.h
+++ b/include/uapi/linux/kvm.h
@@ -972,12 +972,19 @@ struct kvm_irqfd {
__u8 pad[16];
};
+/* For KVM_CAP_ADJUST_CLOCK */
+
+/* Do not use 1, KVM_CHECK_EXTENSION returned it before we had flags. */
+#define KVM_CLOCK_TSC_STABLE 2
+
struct kvm_clock_data {
__u64 clock;
__u32 flags;
__u32 pad[9];
};
+/* For KVM_CAP_SW_TLB */
+
#define KVM_MMU_FSL_BOOKE_NOHV 0
#define KVM_MMU_FSL_BOOKE_HV 1
diff --git a/virt/kvm/arm/pmu.c b/virt/kvm/arm/pmu.c
index 6e9c40eea208..69ccce308458 100644
--- a/virt/kvm/arm/pmu.c
+++ b/virt/kvm/arm/pmu.c
@@ -305,7 +305,7 @@ void kvm_pmu_software_increment(struct kvm_vcpu *vcpu, u64 val)
continue;
type = vcpu_sys_reg(vcpu, PMEVTYPER0_EL0 + i)
& ARMV8_PMU_EVTYPE_EVENT;
- if ((type == ARMV8_PMU_EVTYPE_EVENT_SW_INCR)
+ if ((type == ARMV8_PMUV3_PERFCTR_SW_INCR)
&& (enable & BIT(i))) {
reg = vcpu_sys_reg(vcpu, PMEVCNTR0_EL0 + i) + 1;
reg = lower_32_bits(reg);
@@ -379,7 +379,8 @@ void kvm_pmu_set_counter_event_type(struct kvm_vcpu *vcpu, u64 data,
eventsel = data & ARMV8_PMU_EVTYPE_EVENT;
/* Software increment event does't need to be backed by a perf event */
- if (eventsel == ARMV8_PMU_EVTYPE_EVENT_SW_INCR)
+ if (eventsel == ARMV8_PMUV3_PERFCTR_SW_INCR &&
+ select_idx != ARMV8_PMU_CYCLE_IDX)
return;
memset(&attr, 0, sizeof(struct perf_event_attr));
@@ -391,7 +392,8 @@ void kvm_pmu_set_counter_event_type(struct kvm_vcpu *vcpu, u64 data,
attr.exclude_kernel = data & ARMV8_PMU_EXCLUDE_EL1 ? 1 : 0;
attr.exclude_hv = 1; /* Don't count EL2 events */
attr.exclude_host = 1; /* Don't count host events */
- attr.config = eventsel;
+ attr.config = (select_idx == ARMV8_PMU_CYCLE_IDX) ?
+ ARMV8_PMUV3_PERFCTR_CPU_CYCLES : eventsel;
counter = kvm_pmu_get_counter_value(vcpu, select_idx);
/* The initial sample period (overflow count) of an event. */
diff --git a/virt/kvm/async_pf.c b/virt/kvm/async_pf.c
index 8035cc1eb955..efeceb0a222d 100644
--- a/virt/kvm/async_pf.c
+++ b/virt/kvm/async_pf.c
@@ -91,6 +91,7 @@ static void async_pf_execute(struct work_struct *work)
spin_lock(&vcpu->async_pf.lock);
list_add_tail(&apf->link, &vcpu->async_pf.done);
+ apf->vcpu = NULL;
spin_unlock(&vcpu->async_pf.lock);
/*
@@ -113,6 +114,8 @@ static void async_pf_execute(struct work_struct *work)
void kvm_clear_async_pf_completion_queue(struct kvm_vcpu *vcpu)
{
+ spin_lock(&vcpu->async_pf.lock);
+
/* cancel outstanding work queue item */
while (!list_empty(&vcpu->async_pf.queue)) {
struct kvm_async_pf *work =
@@ -120,6 +123,14 @@ void kvm_clear_async_pf_completion_queue(struct kvm_vcpu *vcpu)
typeof(*work), queue);
list_del(&work->queue);
+ /*
+ * We know it's present in vcpu->async_pf.done, do
+ * nothing here.
+ */
+ if (!work->vcpu)
+ continue;
+
+ spin_unlock(&vcpu->async_pf.lock);
#ifdef CONFIG_KVM_ASYNC_PF_SYNC
flush_work(&work->work);
#else
@@ -129,9 +140,9 @@ void kvm_clear_async_pf_completion_queue(struct kvm_vcpu *vcpu)
kmem_cache_free(async_pf_cache, work);
}
#endif
+ spin_lock(&vcpu->async_pf.lock);
}
- spin_lock(&vcpu->async_pf.lock);
while (!list_empty(&vcpu->async_pf.done)) {
struct kvm_async_pf *work =
list_first_entry(&vcpu->async_pf.done,