qemu-patch-raspberry4/include/hw/s390x/pv.h
David Gibson 651615d92d s390: Recognize confidential-guest-support option
At least some s390 cpu models support "Protected Virtualization" (PV),
a mechanism to protect guests from eavesdropping by a compromised
hypervisor.

This is similar in function to other mechanisms like AMD's SEV and
POWER's PEF, which are controlled by the "confidential-guest-support"
machine option.  s390 is a slightly special case, because we already
supported PV, simply by using a CPU model with the required feature
(S390_FEAT_UNPACK).

To integrate this with the option used by other platforms, we
implement the following compromise:

 - When the confidential-guest-support option is set, s390 will
   recognize it, verify that the CPU can support PV (failing if not)
   and set virtio default options necessary for encrypted or protected
   guests, as on other platforms.  i.e. if confidential-guest-support
   is set, we will either create a guest capable of entering PV mode,
   or fail outright.

 - If confidential-guest-support is not set, guests might still be
   able to enter PV mode, if the CPU has the right model.  This may be
   a little surprising, but shouldn't actually be harmful.

To start a guest supporting Protected Virtualization using the new
option use the command line arguments:
    -object s390-pv-guest,id=pv0 -machine confidential-guest-support=pv0

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Tested-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
2021-02-08 16:57:38 +11:00

76 lines
2.1 KiB
C

/*
* Protected Virtualization header
*
* Copyright IBM Corp. 2020
* Author(s):
* Janosch Frank <frankja@linux.ibm.com>
*
* This work is licensed under the terms of the GNU GPL, version 2 or (at
* your option) any later version. See the COPYING file in the top-level
* directory.
*/
#ifndef HW_S390_PV_H
#define HW_S390_PV_H
#include "qapi/error.h"
#include "sysemu/kvm.h"
#ifdef CONFIG_KVM
#include "cpu.h"
#include "hw/s390x/s390-virtio-ccw.h"
static inline bool s390_is_pv(void)
{
static S390CcwMachineState *ccw;
Object *obj;
if (ccw) {
return ccw->pv;
}
/* we have to bail out for the "none" machine */
obj = object_dynamic_cast(qdev_get_machine(),
TYPE_S390_CCW_MACHINE);
if (!obj) {
return false;
}
ccw = S390_CCW_MACHINE(obj);
return ccw->pv;
}
int s390_pv_vm_enable(void);
void s390_pv_vm_disable(void);
int s390_pv_set_sec_parms(uint64_t origin, uint64_t length);
int s390_pv_unpack(uint64_t addr, uint64_t size, uint64_t tweak);
void s390_pv_prep_reset(void);
int s390_pv_verify(void);
void s390_pv_unshare(void);
void s390_pv_inject_reset_error(CPUState *cs);
#else /* CONFIG_KVM */
static inline bool s390_is_pv(void) { return false; }
static inline int s390_pv_vm_enable(void) { return 0; }
static inline void s390_pv_vm_disable(void) {}
static inline int s390_pv_set_sec_parms(uint64_t origin, uint64_t length) { return 0; }
static inline int s390_pv_unpack(uint64_t addr, uint64_t size, uint64_t tweak) { return 0; }
static inline void s390_pv_prep_reset(void) {}
static inline int s390_pv_verify(void) { return 0; }
static inline void s390_pv_unshare(void) {}
static inline void s390_pv_inject_reset_error(CPUState *cs) {};
#endif /* CONFIG_KVM */
int s390_pv_kvm_init(ConfidentialGuestSupport *cgs, Error **errp);
static inline int s390_pv_init(ConfidentialGuestSupport *cgs, Error **errp)
{
if (!cgs) {
return 0;
}
if (kvm_enabled()) {
return s390_pv_kvm_init(cgs, errp);
}
error_setg(errp, "Protected Virtualization requires KVM");
return -1;
}
#endif /* HW_S390_PV_H */