Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull KVM fixes from Paolo Bonzini:
- Fix FPU refactoring ("kvm: x86: fix load xsave feature warning")
- Fix eager FPU mode (Cc stable)
- AMD bits of MTRR virtualization
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
kvm: x86: fix load xsave feature warning
KVM: x86: apply guest MTRR virtualization on host reserved pages
KVM: SVM: Sync g_pat with guest-written PAT value
KVM: SVM: use NPT page attributes
KVM: count number of assigned devices
KVM: VMX: fix vmwrite to invalid VMCS
KVM: x86: reintroduce kvm_is_mmio_pfn
x86: hyperv: add CPUID bit for crash handlers
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 2a7f5d7..49ec903 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -604,6 +604,8 @@
bool iommu_noncoherent;
#define __KVM_HAVE_ARCH_NONCOHERENT_DMA
atomic_t noncoherent_dma_count;
+#define __KVM_HAVE_ARCH_ASSIGNED_DEVICE
+ atomic_t assigned_device_count;
struct kvm_pic *vpic;
struct kvm_ioapic *vioapic;
struct kvm_pit *vpit;
diff --git a/arch/x86/include/uapi/asm/hyperv.h b/arch/x86/include/uapi/asm/hyperv.h
index 8fba544..f36d56b 100644
--- a/arch/x86/include/uapi/asm/hyperv.h
+++ b/arch/x86/include/uapi/asm/hyperv.h
@@ -108,6 +108,8 @@
#define HV_X64_HYPERCALL_PARAMS_XMM_AVAILABLE (1 << 4)
/* Support for a virtual guest idle state is available */
#define HV_X64_GUEST_IDLE_STATE_AVAILABLE (1 << 5)
+/* Guest crash data handler available */
+#define HV_X64_GUEST_CRASH_MSR_AVAILABLE (1 << 10)
/*
* Implementation recommendations. Indicates which behaviors the hypervisor
diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c
index 64dd467..2fbea25 100644
--- a/arch/x86/kvm/cpuid.c
+++ b/arch/x86/kvm/cpuid.c
@@ -98,6 +98,8 @@
best->ebx = xstate_required_size(vcpu->arch.xcr0, true);
vcpu->arch.eager_fpu = use_eager_fpu() || guest_cpuid_has_mpx(vcpu);
+ if (vcpu->arch.eager_fpu)
+ kvm_x86_ops->fpu_activate(vcpu);
/*
* The existing code assumes virtual address is 48-bit in the canonical
diff --git a/arch/x86/kvm/iommu.c b/arch/x86/kvm/iommu.c
index 7dbced3..5c520eb 100644
--- a/arch/x86/kvm/iommu.c
+++ b/arch/x86/kvm/iommu.c
@@ -200,6 +200,7 @@
goto out_unmap;
}
+ kvm_arch_start_assignment(kvm);
pci_set_dev_assigned(pdev);
dev_info(&pdev->dev, "kvm assign device\n");
@@ -224,6 +225,7 @@
iommu_detach_device(domain, &pdev->dev);
pci_clear_dev_assigned(pdev);
+ kvm_arch_end_assignment(kvm);
dev_info(&pdev->dev, "kvm deassign device\n");
diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c
index f807496..4417146 100644
--- a/arch/x86/kvm/mmu.c
+++ b/arch/x86/kvm/mmu.c
@@ -2479,6 +2479,14 @@
return 0;
}
+static bool kvm_is_mmio_pfn(pfn_t pfn)
+{
+ if (pfn_valid(pfn))
+ return !is_zero_pfn(pfn) && PageReserved(pfn_to_page(pfn));
+
+ return true;
+}
+
static int set_spte(struct kvm_vcpu *vcpu, u64 *sptep,
unsigned pte_access, int level,
gfn_t gfn, pfn_t pfn, bool speculative,
@@ -2506,7 +2514,7 @@
spte |= PT_PAGE_SIZE_MASK;
if (tdp_enabled)
spte |= kvm_x86_ops->get_mt_mask(vcpu, gfn,
- kvm_is_reserved_pfn(pfn));
+ kvm_is_mmio_pfn(pfn));
if (host_writable)
spte |= SPTE_HOST_WRITEABLE;
diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
index 602b974..bbc678a 100644
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -865,6 +865,64 @@
set_msr_interception(msrpm, MSR_IA32_LASTINTTOIP, 0, 0);
}
+#define MTRR_TYPE_UC_MINUS 7
+#define MTRR2PROTVAL_INVALID 0xff
+
+static u8 mtrr2protval[8];
+
+static u8 fallback_mtrr_type(int mtrr)
+{
+ /*
+ * WT and WP aren't always available in the host PAT. Treat
+ * them as UC and UC- respectively. Everything else should be
+ * there.
+ */
+ switch (mtrr)
+ {
+ case MTRR_TYPE_WRTHROUGH:
+ return MTRR_TYPE_UNCACHABLE;
+ case MTRR_TYPE_WRPROT:
+ return MTRR_TYPE_UC_MINUS;
+ default:
+ BUG();
+ }
+}
+
+static void build_mtrr2protval(void)
+{
+ int i;
+ u64 pat;
+
+ for (i = 0; i < 8; i++)
+ mtrr2protval[i] = MTRR2PROTVAL_INVALID;
+
+ /* Ignore the invalid MTRR types. */
+ mtrr2protval[2] = 0;
+ mtrr2protval[3] = 0;
+
+ /*
+ * Use host PAT value to figure out the mapping from guest MTRR
+ * values to nested page table PAT/PCD/PWT values. We do not
+ * want to change the host PAT value every time we enter the
+ * guest.
+ */
+ rdmsrl(MSR_IA32_CR_PAT, pat);
+ for (i = 0; i < 8; i++) {
+ u8 mtrr = pat >> (8 * i);
+
+ if (mtrr2protval[mtrr] == MTRR2PROTVAL_INVALID)
+ mtrr2protval[mtrr] = __cm_idx2pte(i);
+ }
+
+ for (i = 0; i < 8; i++) {
+ if (mtrr2protval[i] == MTRR2PROTVAL_INVALID) {
+ u8 fallback = fallback_mtrr_type(i);
+ mtrr2protval[i] = mtrr2protval[fallback];
+ BUG_ON(mtrr2protval[i] == MTRR2PROTVAL_INVALID);
+ }
+ }
+}
+
static __init int svm_hardware_setup(void)
{
int cpu;
@@ -931,6 +989,7 @@
} else
kvm_disable_tdp();
+ build_mtrr2protval();
return 0;
err:
@@ -1085,6 +1144,39 @@
return target_tsc - tsc;
}
+static void svm_set_guest_pat(struct vcpu_svm *svm, u64 *g_pat)
+{
+ struct kvm_vcpu *vcpu = &svm->vcpu;
+
+ /* Unlike Intel, AMD takes the guest's CR0.CD into account.
+ *
+ * AMD does not have IPAT. To emulate it for the case of guests
+ * with no assigned devices, just set everything to WB. If guests
+ * have assigned devices, however, we cannot force WB for RAM
+ * pages only, so use the guest PAT directly.
+ */
+ if (!kvm_arch_has_assigned_device(vcpu->kvm))
+ *g_pat = 0x0606060606060606;
+ else
+ *g_pat = vcpu->arch.pat;
+}
+
+static u64 svm_get_mt_mask(struct kvm_vcpu *vcpu, gfn_t gfn, bool is_mmio)
+{
+ u8 mtrr;
+
+ /*
+ * 1. MMIO: trust guest MTRR, so same as item 3.
+ * 2. No passthrough: always map as WB, and force guest PAT to WB as well
+ * 3. Passthrough: can't guarantee the result, try to trust guest.
+ */
+ if (!is_mmio && !kvm_arch_has_assigned_device(vcpu->kvm))
+ return 0;
+
+ mtrr = kvm_mtrr_get_guest_memory_type(vcpu, gfn);
+ return mtrr2protval[mtrr];
+}
+
static void init_vmcb(struct vcpu_svm *svm, bool init_event)
{
struct vmcb_control_area *control = &svm->vmcb->control;
@@ -1180,6 +1272,7 @@
clr_cr_intercept(svm, INTERCEPT_CR3_READ);
clr_cr_intercept(svm, INTERCEPT_CR3_WRITE);
save->g_pat = svm->vcpu.arch.pat;
+ svm_set_guest_pat(svm, &save->g_pat);
save->cr3 = 0;
save->cr4 = 0;
}
@@ -3254,6 +3347,16 @@
case MSR_VM_IGNNE:
vcpu_unimpl(vcpu, "unimplemented wrmsr: 0x%x data 0x%llx\n", ecx, data);
break;
+ case MSR_IA32_CR_PAT:
+ if (npt_enabled) {
+ if (!kvm_mtrr_valid(vcpu, MSR_IA32_CR_PAT, data))
+ return 1;
+ vcpu->arch.pat = data;
+ svm_set_guest_pat(svm, &svm->vmcb->save.g_pat);
+ mark_dirty(svm->vmcb, VMCB_NPT);
+ break;
+ }
+ /* fall through */
default:
return kvm_set_msr_common(vcpu, msr);
}
@@ -4088,11 +4191,6 @@
return true;
}
-static u64 svm_get_mt_mask(struct kvm_vcpu *vcpu, gfn_t gfn, bool is_mmio)
-{
- return 0;
-}
-
static void svm_cpuid_update(struct kvm_vcpu *vcpu)
{
}
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index e856dd5..5b4e938 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -8632,22 +8632,17 @@
u64 ipat = 0;
/* For VT-d and EPT combination
- * 1. MMIO: always map as UC
+ * 1. MMIO: guest may want to apply WC, trust it.
* 2. EPT with VT-d:
* a. VT-d without snooping control feature: can't guarantee the
- * result, try to trust guest.
+ * result, try to trust guest. So the same as item 1.
* b. VT-d with snooping control feature: snooping control feature of
* VT-d engine can guarantee the cache correctness. Just set it
* to WB to keep consistent with host. So the same as item 3.
* 3. EPT without VT-d: always map as WB and set IPAT=1 to keep
* consistent with host MTRR
*/
- if (is_mmio) {
- cache = MTRR_TYPE_UNCACHABLE;
- goto exit;
- }
-
- if (!kvm_arch_has_noncoherent_dma(vcpu->kvm)) {
+ if (!is_mmio && !kvm_arch_has_noncoherent_dma(vcpu->kvm)) {
ipat = VMX_EPT_IPAT_BIT;
cache = MTRR_TYPE_WRBACK;
goto exit;
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index bbaf44e..5ef2560 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -3157,8 +3157,7 @@
cpuid_count(XSTATE_CPUID, index,
&size, &offset, &ecx, &edx);
memcpy(dest, src + offset, size);
- } else
- WARN_ON_ONCE(1);
+ }
valid -= feature;
}
@@ -7315,11 +7314,6 @@
vcpu = kvm_x86_ops->vcpu_create(kvm, id);
- /*
- * Activate fpu unconditionally in case the guest needs eager FPU. It will be
- * deactivated soon if it doesn't.
- */
- kvm_x86_ops->fpu_activate(vcpu);
return vcpu;
}
@@ -8218,6 +8212,24 @@
kvm_x86_ops->interrupt_allowed(vcpu);
}
+void kvm_arch_start_assignment(struct kvm *kvm)
+{
+ atomic_inc(&kvm->arch.assigned_device_count);
+}
+EXPORT_SYMBOL_GPL(kvm_arch_start_assignment);
+
+void kvm_arch_end_assignment(struct kvm *kvm)
+{
+ atomic_dec(&kvm->arch.assigned_device_count);
+}
+EXPORT_SYMBOL_GPL(kvm_arch_end_assignment);
+
+bool kvm_arch_has_assigned_device(struct kvm *kvm)
+{
+ return atomic_read(&kvm->arch.assigned_device_count);
+}
+EXPORT_SYMBOL_GPL(kvm_arch_has_assigned_device);
+
void kvm_arch_register_noncoherent_dma(struct kvm *kvm)
{
atomic_inc(&kvm->arch.noncoherent_dma_count);
diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index 9564fd7..05e99b8 100644
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -734,6 +734,24 @@
return false;
}
#endif
+#ifdef __KVM_HAVE_ARCH_ASSIGNED_DEVICE
+void kvm_arch_start_assignment(struct kvm *kvm);
+void kvm_arch_end_assignment(struct kvm *kvm);
+bool kvm_arch_has_assigned_device(struct kvm *kvm);
+#else
+static inline void kvm_arch_start_assignment(struct kvm *kvm)
+{
+}
+
+static inline void kvm_arch_end_assignment(struct kvm *kvm)
+{
+}
+
+static inline bool kvm_arch_has_assigned_device(struct kvm *kvm)
+{
+ return false;
+}
+#endif
static inline wait_queue_head_t *kvm_arch_vcpu_wq(struct kvm_vcpu *vcpu)
{
diff --git a/virt/kvm/vfio.c b/virt/kvm/vfio.c
index 620e37f..1dd087d 100644
--- a/virt/kvm/vfio.c
+++ b/virt/kvm/vfio.c
@@ -155,6 +155,8 @@
list_add_tail(&kvg->node, &kv->group_list);
kvg->vfio_group = vfio_group;
+ kvm_arch_start_assignment(dev->kvm);
+
mutex_unlock(&kv->lock);
kvm_vfio_update_coherency(dev);
@@ -190,6 +192,8 @@
break;
}
+ kvm_arch_end_assignment(dev->kvm);
+
mutex_unlock(&kv->lock);
kvm_vfio_group_put_external_user(vfio_group);
@@ -239,6 +243,7 @@
kvm_vfio_group_put_external_user(kvg->vfio_group);
list_del(&kvg->node);
kfree(kvg);
+ kvm_arch_end_assignment(dev->kvm);
}
kvm_vfio_update_coherency(dev);