Merge git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull KVM updates from Marcelo Tosatti.

* git://git.kernel.org/pub/scm/virt/kvm/kvm:
  KVM: lock slots_lock around device assignment
  KVM: VMX: Fix kvm_set_shared_msr() called in preemptible context
  KVM: unmap pages from the iommu when slots are removed
  KVM: PMU emulation: GLOBAL_CTRL MSR should be enabled on reset

5 files changed, 43 insertions, 21 deletions

diff --git a/arch/x86/kvm/pmu.c b/arch/x86/kvm/pmu.c
index 173df38dbda5..2e88438ffd83 100644
--- a/arch/x86/kvm/pmu.c
+++ b/arch/x86/kvm/pmu.c
@@ -459,17 +459,17 @@ void kvm_pmu_cpuid_update(struct kvm_vcpu *vcpu)
         pmu->available_event_types = ~entry->ebx & ((1ull << bitmap_len) - 1);
 
         if (pmu->version == 1) {
-                pmu->global_ctrl = (1 << pmu->nr_arch_gp_counters) - 1;
-                return;
+                pmu->nr_arch_fixed_counters = 0;
+        } else {
+                pmu->nr_arch_fixed_counters = min((int)(entry->edx & 0x1f),
+                                X86_PMC_MAX_FIXED);
+                pmu->counter_bitmask[KVM_PMC_FIXED] =
+                        ((u64)1 << ((entry->edx >> 5) & 0xff)) - 1;
         }
 
-        pmu->nr_arch_fixed_counters = min((int)(entry->edx & 0x1f),
-                        X86_PMC_MAX_FIXED);
-        pmu->counter_bitmask[KVM_PMC_FIXED] =
-                ((u64)1 << ((entry->edx >> 5) & 0xff)) - 1;
-        pmu->global_ctrl_mask = ~(((1 << pmu->nr_arch_gp_counters) - 1)
-                        | (((1ull << pmu->nr_arch_fixed_counters) - 1)
-                                << X86_PMC_IDX_FIXED));
+        pmu->global_ctrl = ((1 << pmu->nr_arch_gp_counters) - 1) |
+                (((1ull << pmu->nr_arch_fixed_counters) - 1) << X86_PMC_IDX_FIXED);
+        pmu->global_ctrl_mask = ~pmu->global_ctrl;
 }
 
 void kvm_pmu_init(struct kvm_vcpu *vcpu)
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index ad85adfef843..4ff0ab9bc3c8 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -2210,9 +2210,12 @@ static int vmx_set_msr(struct kvm_vcpu *vcpu, u32 msr_index, u64 data)
                 msr = find_msr_entry(vmx, msr_index);
                 if (msr) {
                         msr->data = data;
-                        if (msr - vmx->guest_msrs < vmx->save_nmsrs)
+                        if (msr - vmx->guest_msrs < vmx->save_nmsrs) {
+                                preempt_disable();
                                 kvm_set_shared_msr(msr->index, msr->data,
                                                    msr->mask);
+                                preempt_enable();
+                        }
                         break;
                 }
                 ret = kvm_set_msr_common(vcpu, msr_index, data);
diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index 665a260c7e09..72cbf08d45fb 100644
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -596,6 +596,7 @@ void kvm_free_irq_source_id(struct kvm *kvm, int irq_source_id);
 
 #ifdef CONFIG_IOMMU_API
 int kvm_iommu_map_pages(struct kvm *kvm, struct kvm_memory_slot *slot);
+void kvm_iommu_unmap_pages(struct kvm *kvm, struct kvm_memory_slot *slot);
 int kvm_iommu_map_guest(struct kvm *kvm);
 int kvm_iommu_unmap_guest(struct kvm *kvm);
 int kvm_assign_device(struct kvm *kvm,
@@ -609,6 +610,11 @@ static inline int kvm_iommu_map_pages(struct kvm *kvm,
         return 0;
 }
 
+static inline void kvm_iommu_unmap_pages(struct kvm *kvm,
+                                         struct kvm_memory_slot *slot)
+{
+}
+
 static inline int kvm_iommu_map_guest(struct kvm *kvm)
 {
         return -ENODEV;
diff --git a/virt/kvm/iommu.c b/virt/kvm/iommu.c
index a457d2138f49..e9fff9830bf0 100644
--- a/virt/kvm/iommu.c
+++ b/virt/kvm/iommu.c
@@ -240,9 +240,13 @@ int kvm_iommu_map_guest(struct kvm *kvm)
                 return -ENODEV;
         }
 
+        mutex_lock(&kvm->slots_lock);
+
         kvm->arch.iommu_domain = iommu_domain_alloc(&pci_bus_type);
-        if (!kvm->arch.iommu_domain)
-                return -ENOMEM;
+        if (!kvm->arch.iommu_domain) {
+                r = -ENOMEM;
+                goto out_unlock;
+        }
 
         if (!allow_unsafe_assigned_interrupts &&
             !iommu_domain_has_cap(kvm->arch.iommu_domain,
@@ -253,17 +257,16 @@ int kvm_iommu_map_guest(struct kvm *kvm)
                        " module option.\n", __func__);
                 iommu_domain_free(kvm->arch.iommu_domain);
                 kvm->arch.iommu_domain = NULL;
-                return -EPERM;
+                r = -EPERM;
+                goto out_unlock;
         }
 
         r = kvm_iommu_map_memslots(kvm);
         if (r)
-                goto out_unmap;
-
-        return 0;
+                kvm_iommu_unmap_memslots(kvm);
 
-out_unmap:
-        kvm_iommu_unmap_memslots(kvm);
+out_unlock:
+        mutex_unlock(&kvm->slots_lock);
         return r;
 }
 
@@ -310,6 +313,11 @@ static void kvm_iommu_put_pages(struct kvm *kvm,
         }
 }
 
+void kvm_iommu_unmap_pages(struct kvm *kvm, struct kvm_memory_slot *slot)
+{
+        kvm_iommu_put_pages(kvm, slot->base_gfn, slot->npages);
+}
+
 static int kvm_iommu_unmap_memslots(struct kvm *kvm)
 {
         int idx;
@@ -320,7 +328,7 @@ static int kvm_iommu_unmap_memslots(struct kvm *kvm)
         slots = kvm_memslots(kvm);
 
         kvm_for_each_memslot(memslot, slots)
-                kvm_iommu_put_pages(kvm, memslot->base_gfn, memslot->npages);
+                kvm_iommu_unmap_pages(kvm, memslot);
 
         srcu_read_unlock(&kvm->srcu, idx);
 
@@ -335,7 +343,11 @@ int kvm_iommu_unmap_guest(struct kvm *kvm)
         if (!domain)
                 return 0;
 
+        mutex_lock(&kvm->slots_lock);
         kvm_iommu_unmap_memslots(kvm);
+        kvm->arch.iommu_domain = NULL;
+        mutex_unlock(&kvm->slots_lock);
+
         iommu_domain_free(domain);
         return 0;
 }
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index 42b73930a6de..9739b533ca2e 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -808,12 +808,13 @@ int __kvm_set_memory_region(struct kvm *kvm,
         if (r)
                 goto out_free;
 
-        /* map the pages in iommu page table */
+        /* map/unmap the pages in iommu page table */
         if (npages) {
                 r = kvm_iommu_map_pages(kvm, &new);
                 if (r)
                         goto out_free;
-        }
+        } else
+                kvm_iommu_unmap_pages(kvm, &old);
 
         r = -ENOMEM;
         slots = kmemdup(kvm->memslots, sizeof(struct kvm_memslots),