i386/cpu: Set SEV-SNP CPUID bit when SNP enabled

SNP guests will rely on this bit to determine certain feature support.

Signed-off-by: Michael Roth <michael.roth@amd.com>
Signed-off-by: Pankaj Gupta <pankaj.gupta@amd.com>
Message-ID: <20240530111643.1091816-12-pankaj.gupta@amd.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

diff --git a/target/i386/cpu.c b/target/i386/cpu.c
index bc2dceb647fa0cc7b528d63b01090208efad5b6f..914bef442c7caf98a282508d7cbec7cd80952fad 100644 (file)
--- a/target/i386/cpu.c
+++ b/target/i386/cpu.c
@@ -6979,6 +6979,7 @@ void cpu_x86_cpuid(CPUX86State *env, uint32_t index, uint32_t count,
         if (sev_enabled()) {
             *eax = 0x2;
             *eax |= sev_es_enabled() ? 0x8 : 0;
+            *eax |= sev_snp_enabled() ? 0x10 : 0;
             *ebx = sev_get_cbit_position() & 0x3f; /* EBX[5:0] */
             *ebx |= (sev_get_reduced_phys_bits() & 0x3f) << 6; /* EBX[11:6] */
         }