@samitouri / QOSamiQemu / commits / 4196b5f0a0

target/i386: SEV: Generalize handling of SVM_SEV_FEAT_SNP_ACTIVE

Align with IGVM files providing SEV features with SVM_SEV_FEAT_SNP_ACTIVE set by setting the same when creating a sev-snp-guest object. Since KVM sets this feature itself, SVM_SEV_FEAT_SNP_ACTIVE is unset before KVM_SEV_INIT2 ioctl is invoked. Move that out of IGVM-specific section to common code. While at it, convert the existing SVM_SEV_FEAT_SNP_ACTIVE definition to use the BIT() macro for consistency with upcoming feature flags. Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com> Signed-off-by: Naveen N Rao (AMD) <naveen@kernel.org> Link: https://lore.kernel.org/r/031de849edf2ae4eaa6e00df83b053605a3ecfea.1779281646.git.naveen@kernel.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Naveen N Rao (AMD) committed May 20, 2026 at 18:57 UTC 4196b5f0a0c01581418263fb8d9f63a179741b2c
2 files changed +18 -8
target/i386/sev.c
+17 -7
@@ -324,6 +324,15 @@ sev_set_guest_state(SevCommonState *sev_common, SevState new_state)
324 sev_common->state = new_state;
325 }
326
327 +static void sev_set_feature(SevCommonState *sev_common, uint64_t feature, bool set)
328 +{
329 + if (set) {
330 + sev_common->sev_features |= feature;
331 + } else {
332 + sev_common->sev_features &= ~feature;
333 + }
334 +}
335 +
336 static void
337 sev_ram_block_added(RAMBlockNotifier *n, void *host, size_t size,
338 size_t max_size)
@@ -1899,15 +1908,15 @@ static int sev_common_kvm_init(ConfidentialGuestSupport *cgs, Error **errp)
1908 ->process(x86machine->igvm, machine, true, errp) == -1) {
1909 return -1;
1910 }
1902 - /*
1903 - * KVM maintains a bitmask of allowed sev_features. This does not
1904 - * include SVM_SEV_FEAT_SNP_ACTIVE which is set accordingly by KVM
1905 - * itself. Therefore we need to clear this flag.
1906 - */
1907 - args.vmsa_features = sev_common->sev_features &
1908 - ~SVM_SEV_FEAT_SNP_ACTIVE;
1911 }
1912
1913 + /*
1914 + * KVM maintains a bitmask of allowed sev_features. This does not
1915 + * include SVM_SEV_FEAT_SNP_ACTIVE which is set accordingly by KVM
1916 + * itself. Therefore we need to clear this flag.
1917 + */
1918 + args.vmsa_features = sev_common->sev_features & ~SVM_SEV_FEAT_SNP_ACTIVE;
1919 +
1920 ret = sev_ioctl(sev_common->sev_fd, KVM_SEV_INIT2, &args, &fw_error);
1921 break;
1922 }
@@ -3211,6 +3220,7 @@ sev_snp_guest_instance_init(Object *obj)
3220
3221 /* default init/start/finish params for kvm */
3222 sev_snp_guest->kvm_start_conf.policy = DEFAULT_SEV_SNP_POLICY;
3223 + sev_set_feature(SEV_COMMON(sev_snp_guest), SVM_SEV_FEAT_SNP_ACTIVE, true);
3224 }
3225
3226 static void
target/i386/sev.h
+1 -1
@@ -46,7 +46,7 @@ bool sev_snp_enabled(void);
46 #define SEV_SNP_POLICY_SMT 0x10000
47 #define SEV_SNP_POLICY_DBG 0x80000
48
49 -#define SVM_SEV_FEAT_SNP_ACTIVE 1
49 +#define SVM_SEV_FEAT_SNP_ACTIVE BIT(0)
50
51 typedef struct SevKernelLoaderContext {
52 char *setup_data;