diff options
Diffstat (limited to 'target/i386/sev.c')
| -rw-r--r-- | target/i386/sev.c | 17 |
1 files changed, 14 insertions, 3 deletions
diff --git a/target/i386/sev.c b/target/i386/sev.c index 859e06f..fe2144c 100644 --- a/target/i386/sev.c +++ b/target/i386/sev.c @@ -932,15 +932,26 @@ int sev_kvm_init(ConfidentialGuestSupport *cgs, Error **errp) host_cpuid(0x8000001F, 0, NULL, &ebx, NULL, NULL); host_cbitpos = ebx & 0x3f; + /* + * The cbitpos value will be placed in bit positions 5:0 of the EBX + * register of CPUID 0x8000001F. No need to verify the range as the + * comparison against the host value accomplishes that. + */ if (host_cbitpos != sev->cbitpos) { error_setg(errp, "%s: cbitpos check failed, host '%d' requested '%d'", __func__, host_cbitpos, sev->cbitpos); goto err; } - if (sev->reduced_phys_bits < 1) { - error_setg(errp, "%s: reduced_phys_bits check failed, it should be >=1," - " requested '%d'", __func__, sev->reduced_phys_bits); + /* + * The reduced-phys-bits value will be placed in bit positions 11:6 of + * the EBX register of CPUID 0x8000001F, so verify the supplied value + * is in the range of 1 to 63. + */ + if (sev->reduced_phys_bits < 1 || sev->reduced_phys_bits > 63) { + error_setg(errp, "%s: reduced_phys_bits check failed," + " it should be in the range of 1 to 63, requested '%d'", + __func__, sev->reduced_phys_bits); goto err; } |