| Message ID | 20220810193033.1090251-8-pcc@google.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | KVM: arm64: permit MAP_SHARED mappings with MTE enabled | expand |
On Wed, Aug 10, 2022 at 12:30:33PM -0700, Peter Collingbourne wrote: > Document both the restriction on VM_MTE_ALLOWED mappings and > the relaxation for shared mappings. > > Signed-off-by: Peter Collingbourne <pcc@google.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com>
diff --git a/Documentation/virt/kvm/api.rst b/Documentation/virt/kvm/api.rst index 9788b19f9ff7..30e0c35828ef 100644 --- a/Documentation/virt/kvm/api.rst +++ b/Documentation/virt/kvm/api.rst @@ -7486,8 +7486,9 @@ hibernation of the host; however the VMM needs to manually save/restore the tags as appropriate if the VM is migrated. When this capability is enabled all memory in memslots must be mapped as -not-shareable (no MAP_SHARED), attempts to create a memslot with a -MAP_SHARED mmap will result in an -EINVAL return. +``MAP_ANONYMOUS`` or with a RAM-based file mapping (``tmpfs``, ``memfd``), +attempts to create a memslot with an invalid mmap will result in an +-EINVAL return. When enabled the VMM may make use of the ``KVM_ARM_MTE_COPY_TAGS`` ioctl to perform a bulk copy of tags to/from the guest.
Document both the restriction on VM_MTE_ALLOWED mappings and the relaxation for shared mappings. Signed-off-by: Peter Collingbourne <pcc@google.com> --- Documentation/virt/kvm/api.rst | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-)