| Message ID | 20221104011041.290951-9-pcc@google.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | KVM: arm64: permit MAP_SHARED mappings with MTE enabled | expand |
On Thu, Nov 03 2022, Peter Collingbourne <pcc@google.com> 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> > --- > Documentation/virt/kvm/api.rst | 5 +++-- > 1 file changed, 3 insertions(+), 2 deletions(-) Reviewed-by: Cornelia Huck <cohuck@redhat.com>
diff --git a/Documentation/virt/kvm/api.rst b/Documentation/virt/kvm/api.rst index eee9f857a986..b55f80dadcfe 100644 --- a/Documentation/virt/kvm/api.rst +++ b/Documentation/virt/kvm/api.rst @@ -7385,8 +7385,9 @@ 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.