Hi Alexandru,
On 3/21/22 3:28 PM, Alexandru Elisei wrote:
> MTE has been supported in Linux since commit 673638f434ee ("KVM: arm64:
> Expose KVM_ARM_CAP_MTE"), add support for it in kvmtool.
>
> Signed-off-by: Alexandru Elisei <alexandru.elisei@xxxxxxx>
> ---
> arm/aarch32/include/kvm/kvm-arch.h | 3 +++
> arm/aarch64/include/kvm/kvm-arch.h | 1 +
> arm/aarch64/include/kvm/kvm-config-arch.h | 2 ++
> arm/aarch64/kvm.c | 13 +++++++++++++
> arm/include/arm-common/kvm-config-arch.h | 1 +
> arm/kvm.c | 3 +++
> 6 files changed, 23 insertions(+)
>
> diff --git a/arm/aarch32/include/kvm/kvm-arch.h b/arm/aarch32/include/kvm/kvm-arch.h
> index bee2fc255a82..5616b27e257e 100644
> --- a/arm/aarch32/include/kvm/kvm-arch.h
> +++ b/arm/aarch32/include/kvm/kvm-arch.h
> @@ -5,6 +5,9 @@
>
> #define kvm__arch_get_kern_offset(...) 0x8000
>
> +struct kvm;
> +static inline void kvm__arch_enable_mte(struct kvm *kvm) {}
> +
> #define ARM_MAX_MEMORY(...) ARM_LOMAP_MAX_MEMORY
>
> #define MAX_PAGE_SIZE SZ_4K
> diff --git a/arm/aarch64/include/kvm/kvm-arch.h b/arm/aarch64/include/kvm/kvm-arch.h
> index 5e5ee41211ed..9124f6919d0f 100644
> --- a/arm/aarch64/include/kvm/kvm-arch.h
> +++ b/arm/aarch64/include/kvm/kvm-arch.h
> @@ -6,6 +6,7 @@
> struct kvm;
> unsigned long long kvm__arch_get_kern_offset(struct kvm *kvm, int fd);
> int kvm__arch_get_ipa_limit(struct kvm *kvm);
> +void kvm__arch_enable_mte(struct kvm *kvm);
>
> #define ARM_MAX_MEMORY(kvm) ({ \
> u64 max_ram; \
> diff --git a/arm/aarch64/include/kvm/kvm-config-arch.h b/arm/aarch64/include/kvm/kvm-config-arch.h
> index 04be43dfa9b2..11250365d8d5 100644
> --- a/arm/aarch64/include/kvm/kvm-config-arch.h
> +++ b/arm/aarch64/include/kvm/kvm-config-arch.h
> @@ -6,6 +6,8 @@
> "Run AArch32 guest"), \
> OPT_BOOLEAN('\0', "pmu", &(cfg)->has_pmuv3, \
> "Create PMUv3 device"), \
> + OPT_BOOLEAN('\0', "mte", &(cfg)->has_mte, \
> + "Enable memory tagging extension"), \
> OPT_U64('\0', "kaslr-seed", &(cfg)->kaslr_seed, \
> "Specify random seed for Kernel Address Space " \
> "Layout Randomization (KASLR)"),
> diff --git a/arm/aarch64/kvm.c b/arm/aarch64/kvm.c
> index 56a0aedc263d..46548f8ee96e 100644
> --- a/arm/aarch64/kvm.c
> +++ b/arm/aarch64/kvm.c
> @@ -81,3 +81,16 @@ int kvm__get_vm_type(struct kvm *kvm)
>
> return KVM_VM_TYPE_ARM_IPA_SIZE(ipa_bits);
> }
> +
> +void kvm__arch_enable_mte(struct kvm *kvm)
> +{
> + struct kvm_enable_cap cap = {
> + .cap = KVM_CAP_ARM_MTE,
> + };
> +
> + if (!kvm__supports_extension(kvm, KVM_CAP_ARM_MTE))
> + die("MTE capability is not supported");
> +
> + if (ioctl(kvm->vm_fd, KVM_ENABLE_CAP, &cap))
> + die_perror("KVM_ENABLE_CAP(KVM_CAP_ARM_MTE)");
> +}
> diff --git a/arm/include/arm-common/kvm-config-arch.h b/arm/include/arm-common/kvm-config-arch.h
> index 5734c46ab9e6..16e8d500a71b 100644
> --- a/arm/include/arm-common/kvm-config-arch.h
> +++ b/arm/include/arm-common/kvm-config-arch.h
> @@ -9,6 +9,7 @@ struct kvm_config_arch {
> bool virtio_trans_pci;
> bool aarch32_guest;
> bool has_pmuv3;
> + bool has_mte;
> u64 kaslr_seed;
> enum irqchip_type irqchip;
> u64 fw_addr;
> diff --git a/arm/kvm.c b/arm/kvm.c
> index 80d233f13d0b..f2db93953778 100644
> --- a/arm/kvm.c
> +++ b/arm/kvm.c
> @@ -86,6 +86,9 @@ void kvm__arch_init(struct kvm *kvm, const char *hugetlbfs_path, u64 ram_size)
> /* Create the virtual GIC. */
> if (gic__create(kvm, kvm->cfg.arch.irqchip))
> die("Failed to create virtual GIC");
> +
> + if (kvm->cfg.arch.has_mte)
> + kvm__arch_enable_mte(kvm);
> }
Can we enable it unconditionally if KVM_CAP_ARM_MTE is supported like we do for
PAC and SVE?
Cheers
Vladimir
