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Hallyn" Cc: kvm@vger.kernel.org, linux-arm-kernel@lists.infradead.org, kvmarm@lists.linux.dev, linux-mips@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, kvm-riscv@lists.infradead.org, linux-riscv@lists.infradead.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, linux-security-module@vger.kernel.org, linux-kernel@vger.kernel.org, Chao Peng , Fuad Tabba , Jarkko Sakkinen , Yu Zhang , Vishal Annapurve , Ackerley Tng , Maciej Szmigiero , Vlastimil Babka , David Hildenbrand , Quentin Perret , Michael Roth , Wang , Liam Merwick , Isaku Yamahata , "Kirill A . Shutemov" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Signed-off-by: Sean Christopherson --- Documentation/virt/kvm/api.rst | 32 ++++++++++++++++++++++++++++++++ arch/x86/include/asm/kvm_host.h | 15 +++++++++------ arch/x86/include/uapi/asm/kvm.h | 3 +++ arch/x86/kvm/Kconfig | 12 ++++++++++++ arch/x86/kvm/mmu/mmu_internal.h | 1 + arch/x86/kvm/x86.c | 16 +++++++++++++++- include/uapi/linux/kvm.h | 1 + virt/kvm/Kconfig | 5 +++++ 8 files changed, 78 insertions(+), 7 deletions(-) diff --git a/Documentation/virt/kvm/api.rst b/Documentation/virt/kvm/api.rst index 0ca8561775ac..9f7b95327c2a 100644 --- a/Documentation/virt/kvm/api.rst +++ b/Documentation/virt/kvm/api.rst @@ -147,10 +147,29 @@ described as 'basic' will be available. The new VM has no virtual cpus and no memory. You probably want to use 0 as machine type. =20 +X86: +^^^^ + +Supported X86 VM types can be queried via KVM_CAP_VM_TYPES. + +S390: +^^^^^ + In order to create user controlled virtual machines on S390, check KVM_CAP_S390_UCONTROL and use the flag KVM_VM_S390_UCONTROL as privileged user (CAP_SYS_ADMIN). =20 +MIPS: +^^^^^ + +To use hardware assisted virtualization on MIPS (VZ ASE) rather than +the default trap & emulate implementation (which changes the virtual +memory layout to fit in user mode), check KVM_CAP_MIPS_VZ and use the +flag KVM_VM_MIPS_VZ. + +ARM64: +^^^^^^ + On arm64, the physical address size for a VM (IPA Size limit) is limited to 40bits by default. The limit can be configured if the host supports the extension KVM_CAP_ARM_VM_IPA_SIZE. When supported, use @@ -8554,6 +8573,19 @@ block sizes is exposed in KVM_CAP_ARM_SUPPORTED_BLOC= K_SIZES as a This capability indicates KVM supports per-page memory attributes and ioct= ls KVM_GET_SUPPORTED_MEMORY_ATTRIBUTES/KVM_SET_MEMORY_ATTRIBUTES are availabl= e. =20 +8.41 KVM_CAP_VM_TYPES +--------------------- + +:Capability: KVM_CAP_MEMORY_ATTRIBUTES +:Architectures: x86 +:Type: system ioctl + +This capability returns a bitmap of support VM types. The 1-setting of bi= t @n +means the VM type with value @n is supported. Possible values of @n are:: + + #define KVM_X86_DEFAULT_VM 0 + #define KVM_X86_SW_PROTECTED_VM 1 + 9. Known KVM API problems =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D =20 diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_hos= t.h index 08b44544a330..bbefd79b7950 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -1227,6 +1227,7 @@ enum kvm_apicv_inhibit { }; =20 struct kvm_arch { + unsigned long vm_type; unsigned long n_used_mmu_pages; unsigned long n_requested_mmu_pages; unsigned long n_max_mmu_pages; @@ -2058,6 +2059,12 @@ void kvm_mmu_new_pgd(struct kvm_vcpu *vcpu, gpa_t ne= w_pgd); void kvm_configure_mmu(bool enable_tdp, int tdp_forced_root_level, int tdp_max_root_level, int tdp_huge_page_level); =20 +#ifdef CONFIG_KVM_PRIVATE_MEM +#define kvm_arch_has_private_mem(kvm) ((kvm)->arch.vm_type !=3D KVM_X86_DE= FAULT_VM) +#else +#define kvm_arch_has_private_mem(kvm) false +#endif + static inline u16 kvm_read_ldt(void) { u16 ldt; @@ -2106,14 +2113,10 @@ enum { #define HF_SMM_INSIDE_NMI_MASK (1 << 2) =20 # define KVM_MAX_NR_ADDRESS_SPACES 2 +/* SMM is currently unsupported for guests with private memory. */ +# define kvm_arch_nr_memslot_as_ids(kvm) (kvm_arch_has_private_mem(kvm) ? = 1 : 2) # define kvm_arch_vcpu_memslots_id(vcpu) ((vcpu)->arch.hflags & HF_SMM_MAS= K ? 1 : 0) # define kvm_memslots_for_spte_role(kvm, role) __kvm_memslots(kvm, (role).= smm) - -static inline int kvm_arch_nr_memslot_as_ids(struct kvm *kvm) -{ - return KVM_MAX_NR_ADDRESS_SPACES; -} - #else # define kvm_memslots_for_spte_role(kvm, role) __kvm_memslots(kvm, 0) #endif diff --git a/arch/x86/include/uapi/asm/kvm.h b/arch/x86/include/uapi/asm/kv= m.h index 1a6a1f987949..a448d0964fc0 100644 --- a/arch/x86/include/uapi/asm/kvm.h +++ b/arch/x86/include/uapi/asm/kvm.h @@ -562,4 +562,7 @@ struct kvm_pmu_event_filter { /* x86-specific KVM_EXIT_HYPERCALL flags. */ #define KVM_EXIT_HYPERCALL_LONG_MODE BIT(0) =20 +#define KVM_X86_DEFAULT_VM 0 +#define KVM_X86_SW_PROTECTED_VM 1 + #endif /* _ASM_X86_KVM_H */ diff --git a/arch/x86/kvm/Kconfig b/arch/x86/kvm/Kconfig index a7eb2bdbfb18..029c76bcd1a5 100644 --- a/arch/x86/kvm/Kconfig +++ b/arch/x86/kvm/Kconfig @@ -77,6 +77,18 @@ config KVM_WERROR =20 If in doubt, say "N". =20 +config KVM_SW_PROTECTED_VM + bool "Enable support for KVM software-protected VMs" + depends on EXPERT + depends on X86_64 + select KVM_GENERIC_PRIVATE_MEM + help + Enable support for KVM software-protected VMs. Currently "protected" + means the VM can be backed with memory provided by + KVM_CREATE_GUEST_MEMFD. + + If unsure, say "N". + config KVM_INTEL tristate "KVM for Intel (and compatible) processors support" depends on KVM && IA32_FEAT_CTL diff --git a/arch/x86/kvm/mmu/mmu_internal.h b/arch/x86/kvm/mmu/mmu_interna= l.h index 268b517e88cb..f1786698ae00 100644 --- a/arch/x86/kvm/mmu/mmu_internal.h +++ b/arch/x86/kvm/mmu/mmu_internal.h @@ -301,6 +301,7 @@ static inline int kvm_mmu_do_page_fault(struct kvm_vcpu= *vcpu, gpa_t cr2_or_gpa, .max_level =3D KVM_MAX_HUGEPAGE_LEVEL, .req_level =3D PG_LEVEL_4K, .goal_level =3D PG_LEVEL_4K, + .is_private =3D kvm_mem_is_private(vcpu->kvm, cr2_or_gpa >> PAGE_SHIFT), }; int r; =20 diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 463ecf70cec0..de195ad83ec0 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -4427,6 +4427,13 @@ static int kvm_ioctl_get_supported_hv_cpuid(struct k= vm_vcpu *vcpu, return 0; } =20 +static bool kvm_is_vm_type_supported(unsigned long type) +{ + return type =3D=3D KVM_X86_DEFAULT_VM || + (type =3D=3D KVM_X86_SW_PROTECTED_VM && + IS_ENABLED(CONFIG_KVM_SW_PROTECTED_VM) && tdp_enabled); +} + int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext) { int r =3D 0; @@ -4617,6 +4624,11 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, lo= ng ext) case KVM_CAP_X86_NOTIFY_VMEXIT: r =3D kvm_caps.has_notify_vmexit; break; + case KVM_CAP_VM_TYPES: + r =3D BIT(KVM_X86_DEFAULT_VM); + if (kvm_is_vm_type_supported(KVM_X86_SW_PROTECTED_VM)) + r |=3D BIT(KVM_X86_SW_PROTECTED_VM); + break; default: break; } @@ -12274,9 +12286,11 @@ int kvm_arch_init_vm(struct kvm *kvm, unsigned lon= g type) int ret; unsigned long flags; =20 - if (type) + if (!kvm_is_vm_type_supported(type)) return -EINVAL; =20 + kvm->arch.vm_type =3D type; + ret =3D kvm_page_track_init(kvm); if (ret) goto out; diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h index 17b12ee8b70e..eb900344a054 100644 --- a/include/uapi/linux/kvm.h +++ b/include/uapi/linux/kvm.h @@ -1216,6 +1216,7 @@ struct kvm_ppc_resize_hpt { #define KVM_CAP_ARM_SUPPORTED_BLOCK_SIZES 229 #define KVM_CAP_USER_MEMORY2 230 #define KVM_CAP_MEMORY_ATTRIBUTES 231 +#define KVM_CAP_VM_TYPES 232 =20 #ifdef KVM_CAP_IRQ_ROUTING =20 diff --git a/virt/kvm/Kconfig b/virt/kvm/Kconfig index 3ee3205e0b39..1a48cb530092 100644 --- a/virt/kvm/Kconfig +++ b/virt/kvm/Kconfig @@ -107,3 +107,8 @@ config KVM_GENERIC_MEMORY_ATTRIBUTES config KVM_PRIVATE_MEM select XARRAY_MULTI bool + +config KVM_GENERIC_PRIVATE_MEM + select KVM_GENERIC_MEMORY_ATTRIBUTES + select KVM_PRIVATE_MEM + bool --=20 2.41.0.255.g8b1d071c50-goog