qemu/target/i386/sev-stub.c
Paolo Bonzini b2f73a0784 sev/i386: Allow AP booting under SEV-ES
When SEV-ES is enabled, it is not possible modify the guests register
state after it has been initially created, encrypted and measured.

Normally, an INIT-SIPI-SIPI request is used to boot the AP. However, the
hypervisor cannot emulate this because it cannot update the AP register
state. For the very first boot by an AP, the reset vector CS segment
value and the EIP value must be programmed before the register has been
encrypted and measured. Search the guest firmware for the guest for a
specific GUID that tells Qemu the value of the reset vector to use.

Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Marcel Apfelbaum <marcel.apfelbaum@gmail.com>
Cc: Richard Henderson <richard.henderson@linaro.org>
Cc: Eduardo Habkost <ehabkost@redhat.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Message-Id: <22db2bfb4d6551aed661a9ae95b4fdbef613ca21.1611682609.git.thomas.lendacky@amd.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-02-16 17:15:39 +01:00

77 lines
1.1 KiB
C

/*
* QEMU SEV stub
*
* Copyright Advanced Micro Devices 2018
*
* Authors:
* Brijesh Singh <brijesh.singh@amd.com>
*
* 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 "sev_i386.h"
SevInfo *sev_get_info(void)
{
return NULL;
}
bool sev_enabled(void)
{
return false;
}
uint64_t sev_get_me_mask(void)
{
return ~0;
}
uint32_t sev_get_cbit_position(void)
{
return 0;
}
uint32_t sev_get_reduced_phys_bits(void)
{
return 0;
}
char *sev_get_launch_measurement(void)
{
return NULL;
}
SevCapability *sev_get_capabilities(Error **errp)
{
error_setg(errp, "SEV is not available in this QEMU");
return NULL;
}
int sev_inject_launch_secret(const char *hdr, const char *secret,
uint64_t gpa, Error **errp)
{
return 1;
}
int sev_encrypt_flash(uint8_t *ptr, uint64_t len, Error **errp)
{
return 0;
}
bool sev_es_enabled(void)
{
return false;
}
void sev_es_set_reset_vector(CPUState *cpu)
{
}
int sev_es_save_reset_vector(void *flash_ptr, uint64_t flash_size)
{
abort();
}