Re: [PATCH v3 1/9] host trust limitation: Introduce new host trust limitation interface

["Dr. David Alan Gilbert" <dgilbert@redhat.com>]

* David Gibson (david@gibson.dropbear.id.au) wrote:
> Several architectures have mechanisms which are designed to protect guest
> memory from interference or eavesdropping by a compromised hypervisor.  AMD
> SEV does this with in-chip memory encryption and Intel has a similar
> mechanism.  POWER's Protected Execution Framework (PEF) accomplishes a
> similar goal using an ultravisor and new memory protection features,
> instead of encryption.
> 
> To (partially) unify handling for these, this introduces a new
> HostTrustLimitation QOM interface.

This does make some sense to me from a SEV point of view, so

Acked-by: Dr. David Alan Gilbert <dgilbert@redhat.com>

> Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
> ---
>  backends/Makefile.objs               |  2 ++
>  backends/host-trust-limitation.c     | 29 ++++++++++++++++++++++++
>  include/exec/host-trust-limitation.h | 33 ++++++++++++++++++++++++++++
>  include/qemu/typedefs.h              |  1 +
>  4 files changed, 65 insertions(+)
>  create mode 100644 backends/host-trust-limitation.c
>  create mode 100644 include/exec/host-trust-limitation.h
> 
> diff --git a/backends/Makefile.objs b/backends/Makefile.objs
> index 28a847cd57..af761c9ab1 100644
> --- a/backends/Makefile.objs
> +++ b/backends/Makefile.objs
> @@ -21,3 +21,5 @@ common-obj-$(CONFIG_LINUX) += hostmem-memfd.o
>  common-obj-$(CONFIG_GIO) += dbus-vmstate.o
>  dbus-vmstate.o-cflags = $(GIO_CFLAGS)
>  dbus-vmstate.o-libs = $(GIO_LIBS)
> +
> +common-obj-y += host-trust-limitation.o
> diff --git a/backends/host-trust-limitation.c b/backends/host-trust-limitation.c
> new file mode 100644
> index 0000000000..96a381cd8a
> --- /dev/null
> +++ b/backends/host-trust-limitation.c
> @@ -0,0 +1,29 @@
> +/*
> + * QEMU Host Trust Limitation interface
> + *
> + * Copyright: David Gibson, Red Hat Inc. 2020
> + *
> + * Authors:
> + *  David Gibson <david@gibson.dropbear.id.au>
> + *
> + * This work is licensed under the terms of the GNU GPL, version 2 or
> + * later.  See the COPYING file in the top-level directory.
> + *
> + */
> +
> +#include "qemu/osdep.h"
> +
> +#include "exec/host-trust-limitation.h"
> +
> +static const TypeInfo host_trust_limitation_info = {
> +    .name = TYPE_HOST_TRUST_LIMITATION,
> +    .parent = TYPE_INTERFACE,
> +    .class_size = sizeof(HostTrustLimitationClass),
> +};
> +
> +static void host_trust_limitation_register_types(void)
> +{
> +    type_register_static(&host_trust_limitation_info);
> +}
> +
> +type_init(host_trust_limitation_register_types)
> diff --git a/include/exec/host-trust-limitation.h b/include/exec/host-trust-limitation.h
> new file mode 100644
> index 0000000000..03887b1be1
> --- /dev/null
> +++ b/include/exec/host-trust-limitation.h
> @@ -0,0 +1,33 @@
> +/*
> + * QEMU Host Trust Limitation interface
> + *
> + * Copyright: David Gibson, Red Hat Inc. 2020
> + *
> + * Authors:
> + *  David Gibson <david@gibson.dropbear.id.au>
> + *
> + * This work is licensed under the terms of the GNU GPL, version 2 or
> + * later.  See the COPYING file in the top-level directory.
> + *
> + */
> +#ifndef QEMU_HOST_TRUST_LIMITATION_H
> +#define QEMU_HOST_TRUST_LIMITATION_H
> +
> +#include "qom/object.h"
> +
> +#define TYPE_HOST_TRUST_LIMITATION "host-trust-limitation"
> +#define HOST_TRUST_LIMITATION(obj)                                    \
> +    INTERFACE_CHECK(HostTrustLimitation, (obj),                       \
> +                    TYPE_HOST_TRUST_LIMITATION)
> +#define HOST_TRUST_LIMITATION_CLASS(klass)                            \
> +    OBJECT_CLASS_CHECK(HostTrustLimitationClass, (klass),             \
> +                       TYPE_HOST_TRUST_LIMITATION)
> +#define HOST_TRUST_LIMITATION_GET_CLASS(obj)                          \
> +    OBJECT_GET_CLASS(HostTrustLimitationClass, (obj),                 \
> +                     TYPE_HOST_TRUST_LIMITATION)
> +
> +typedef struct HostTrustLimitationClass {
> +    InterfaceClass parent;
> +} HostTrustLimitationClass;
> +
> +#endif /* QEMU_HOST_TRUST_LIMITATION_H */
> diff --git a/include/qemu/typedefs.h b/include/qemu/typedefs.h
> index ce4a78b687..f75c7eb2f2 100644
> --- a/include/qemu/typedefs.h
> +++ b/include/qemu/typedefs.h
> @@ -51,6 +51,7 @@ typedef struct FWCfgIoState FWCfgIoState;
>  typedef struct FWCfgMemState FWCfgMemState;
>  typedef struct FWCfgState FWCfgState;
>  typedef struct HostMemoryBackend HostMemoryBackend;
> +typedef struct HostTrustLimitation HostTrustLimitation;
>  typedef struct I2CBus I2CBus;
>  typedef struct I2SCodec I2SCodec;
>  typedef struct IOMMUMemoryRegion IOMMUMemoryRegion;
> -- 
> 2.26.2
> 
--
Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK