On Thu, Jan 14, 2021 at 09:34:36AM +0000, Daniel P. Berrangé wrote: > On Thu, Jan 14, 2021 at 10:58:00AM +1100, David Gibson 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's MKTME can do > > similar things. 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 > > ConfidentialGuestSupport QOM base class. "Confidential" is kind of vague, > > but "confidential computing" seems to be the buzzword about these schemes, > > and "secure" or "protected" are often used in connection to unrelated > > things (such as hypervisor-from-guest or guest-from-guest security). > > > > The "support" in the name is significant because in at least some of the > > cases it requires the guest to take specific actions in order to protect > > itself from hypervisor eavesdropping. > > > > Signed-off-by: David Gibson > > --- > > backends/confidential-guest-support.c | 33 ++++++++++++++++++++ > > backends/meson.build | 1 + > > include/exec/confidential-guest-support.h | 38 +++++++++++++++++++++++ > > include/qemu/typedefs.h | 1 + > > target/i386/sev.c | 3 +- > > 5 files changed, 75 insertions(+), 1 deletion(-) > > create mode 100644 backends/confidential-guest-support.c > > create mode 100644 include/exec/confidential-guest-support.h > > > > diff --git a/backends/confidential-guest-support.c b/backends/confidential-guest-support.c > > new file mode 100644 > > index 0000000000..9b0ded0db4 > > --- /dev/null > > +++ b/backends/confidential-guest-support.c > > @@ -0,0 +1,33 @@ > > +/* > > + * QEMU Confidential Guest support > > + * > > + * Copyright: David Gibson, Red Hat Inc. 2020 > > + * > > + * Authors: > > + * David Gibson > > + * > > + * 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/confidential-guest-support.h" > > + > > +OBJECT_DEFINE_ABSTRACT_TYPE(ConfidentialGuestSupport, > > + confidential_guest_support, > > + CONFIDENTIAL_GUEST_SUPPORT, > > + OBJECT) > > + > > +static void confidential_guest_support_class_init(ObjectClass *oc, void *data) > > +{ > > +} > > + > > +static void confidential_guest_support_init(Object *obj) > > +{ > > +} > > + > > +static void confidential_guest_support_finalize(Object *obj) > > +{ > > +} > > diff --git a/backends/meson.build b/backends/meson.build > > index 484456ece7..d4221831fc 100644 > > --- a/backends/meson.build > > +++ b/backends/meson.build > > @@ -6,6 +6,7 @@ softmmu_ss.add([files( > > 'rng-builtin.c', > > 'rng-egd.c', > > 'rng.c', > > + 'confidential-guest-support.c', > > ), numa]) > > > > softmmu_ss.add(when: 'CONFIG_POSIX', if_true: files('rng-random.c')) > > diff --git a/include/exec/confidential-guest-support.h b/include/exec/confidential-guest-support.h > > new file mode 100644 > > index 0000000000..5f131023ba > > --- /dev/null > > +++ b/include/exec/confidential-guest-support.h > > @@ -0,0 +1,38 @@ > > +/* > > + * QEMU Confidential Guest support > > + * This interface describes the common pieces between various > > + * schemes for protecting guest memory or other state against a > > + * compromised hypervisor. This includes memory encryption (AMD's > > + * SEV and Intel's MKTME) or special protection modes (PEF on POWER, > > + * or PV on s390x). > > + * > > + * Copyright: David Gibson, Red Hat Inc. 2020 > > + * > > + * Authors: > > + * David Gibson > > + * > > + * 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_CONFIDENTIAL_GUEST_SUPPORT_H > > +#define QEMU_CONFIDENTIAL_GUEST_SUPPORT_H > > + > > +#ifndef CONFIG_USER_ONLY > > + > > +#include "qom/object.h" > > + > > +#define TYPE_CONFIDENTIAL_GUEST_SUPPORT "confidential-guest-support" > > +OBJECT_DECLARE_SIMPLE_TYPE(ConfidentialGuestSupport, CONFIDENTIAL_GUEST_SUPPORT) > > + > > +struct ConfidentialGuestSupport { > > + Object parent; > > +}; > > + > > +typedef struct ConfidentialGuestSupportClass { > > + ObjectClass parent; > > +} ConfidentialGuestSupportClass; > > + > > +#endif /* !CONFIG_USER_ONLY */ > > + > > +#endif /* QEMU_CONFIDENTIAL_GUEST_SUPPORT_H */ > > diff --git a/include/qemu/typedefs.h b/include/qemu/typedefs.h > > index 976b529dfb..33685c79ed 100644 > > --- a/include/qemu/typedefs.h > > +++ b/include/qemu/typedefs.h > > @@ -36,6 +36,7 @@ typedef struct BusState BusState; > > typedef struct Chardev Chardev; > > typedef struct CompatProperty CompatProperty; > > typedef struct CoMutex CoMutex; > > +typedef struct ConfidentialGuestSupport ConfidentialGuestSupport; > > typedef struct CPUAddressSpace CPUAddressSpace; > > typedef struct CPUState CPUState; > > typedef struct DeviceListener DeviceListener; > > diff --git a/target/i386/sev.c b/target/i386/sev.c > > index 1546606811..6b49925f51 100644 > > --- a/target/i386/sev.c > > +++ b/target/i386/sev.c > > @@ -31,6 +31,7 @@ > > #include "qom/object.h" > > #include "exec/address-spaces.h" > > #include "monitor/monitor.h" > > +#include "exec/confidential-guest-support.h" > > > > #define TYPE_SEV_GUEST "sev-guest" > > OBJECT_DECLARE_SIMPLE_TYPE(SevGuestState, SEV_GUEST) > > @@ -322,7 +323,7 @@ sev_guest_instance_init(Object *obj) > > > > /* sev guest info */ > > static const TypeInfo sev_guest_info = { > > - .parent = TYPE_OBJECT, > > + .parent = TYPE_CONFIDENTIAL_GUEST_SUPPORT, > > If you're changing the parent QOM type, then you also need to change > the parent struct field type in SevguestState to match Oops, yes. I checked the rest of the types as I made the OBJECT_DECLARE_TYPE conversions, but I forgot to go back and check SEV. > > .name = TYPE_SEV_GUEST, > > .instance_size = sizeof(SevGuestState), > > .instance_finalize = sev_guest_finalize, > > Regards, > Daniel -- David Gibson | I'll have my music baroque, and my code david AT gibson.dropbear.id.au | minimalist, thank you. NOT _the_ _other_ | _way_ _around_! http://www.ozlabs.org/~dgibson