diff options
| author | Steven Price <steven.price@arm.com> | 2021-06-21 12:17:15 +0100 |
|---|---|---|
| committer | Marc Zyngier <maz@kernel.org> | 2021-06-22 14:08:06 +0100 |
| commit | f0376edb1ddcab19a473b4bf1fbd5b6bbed3705b (patch) | |
| tree | 34470ac344cda4f7e8353e0b1392c089bbb3123e /arch/arm64/include | |
| parent | 673638f434ee4a00319e254ade338c57618d6f7e (diff) | |
KVM: arm64: Add ioctl to fetch/store tags in a guest
The VMM may not wish to have it's own mapping of guest memory mapped
with PROT_MTE because this causes problems if the VMM has tag checking
enabled (the guest controls the tags in physical RAM and it's unlikely
the tags are correct for the VMM).
Instead add a new ioctl which allows the VMM to easily read/write the
tags from guest memory, allowing the VMM's mapping to be non-PROT_MTE
while the VMM can still read/write the tags for the purpose of
migration.
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Steven Price <steven.price@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20210621111716.37157-6-steven.price@arm.com
Diffstat (limited to 'arch/arm64/include')
| -rw-r--r-- | arch/arm64/include/asm/kvm_host.h | 3 | ||||
| -rw-r--r-- | arch/arm64/include/asm/mte-def.h | 1 | ||||
| -rw-r--r-- | arch/arm64/include/uapi/asm/kvm.h | 11 |
3 files changed, 15 insertions, 0 deletions
diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h index 74a7447a83a1..c93a7198c242 100644 --- a/arch/arm64/include/asm/kvm_host.h +++ b/arch/arm64/include/asm/kvm_host.h @@ -730,6 +730,9 @@ int kvm_arm_vcpu_arch_get_attr(struct kvm_vcpu *vcpu, int kvm_arm_vcpu_arch_has_attr(struct kvm_vcpu *vcpu, struct kvm_device_attr *attr); +long kvm_vm_ioctl_mte_copy_tags(struct kvm *kvm, + struct kvm_arm_copy_mte_tags *copy_tags); + /* Guest/host FPSIMD coordination helpers */ int kvm_arch_vcpu_run_map_fp(struct kvm_vcpu *vcpu); void kvm_arch_vcpu_load_fp(struct kvm_vcpu *vcpu); diff --git a/arch/arm64/include/asm/mte-def.h b/arch/arm64/include/asm/mte-def.h index cf241b0f0a42..626d359b396e 100644 --- a/arch/arm64/include/asm/mte-def.h +++ b/arch/arm64/include/asm/mte-def.h @@ -7,6 +7,7 @@ #define MTE_GRANULE_SIZE UL(16) #define MTE_GRANULE_MASK (~(MTE_GRANULE_SIZE - 1)) +#define MTE_GRANULES_PER_PAGE (PAGE_SIZE / MTE_GRANULE_SIZE) #define MTE_TAG_SHIFT 56 #define MTE_TAG_SIZE 4 #define MTE_TAG_MASK GENMASK((MTE_TAG_SHIFT + (MTE_TAG_SIZE - 1)), MTE_TAG_SHIFT) diff --git a/arch/arm64/include/uapi/asm/kvm.h b/arch/arm64/include/uapi/asm/kvm.h index 24223adae150..b3edde68bc3e 100644 --- a/arch/arm64/include/uapi/asm/kvm.h +++ b/arch/arm64/include/uapi/asm/kvm.h @@ -184,6 +184,17 @@ struct kvm_vcpu_events { __u32 reserved[12]; }; +struct kvm_arm_copy_mte_tags { + __u64 guest_ipa; + __u64 length; + void __user *addr; + __u64 flags; + __u64 reserved[2]; +}; + +#define KVM_ARM_TAGS_TO_GUEST 0 +#define KVM_ARM_TAGS_FROM_GUEST 1 + /* If you need to interpret the index values, here is the key: */ #define KVM_REG_ARM_COPROC_MASK 0x000000000FFF0000 #define KVM_REG_ARM_COPROC_SHIFT 16 |