Commit 4928cd6d authored by Eduardo Habkost's avatar Eduardo Habkost
Browse files

target-i386: xsave: Calculate enabled components only once 



Instead of checking both env->features and ena_mask at two
different places in the CPUID code, initialize ena_mask based on
the features that are enabled for the CPU, and then clear
unsupported bits based on kvm_arch_get_supported_cpuid().

The results should be exactly the same, but it will make it
easier to move the mask calculation elsewhare, and reuse
x86_cpu_filter_features() for the kvm_arch_get_supported_cpuid()
check.

Reviewed-by: default avatarRichard Henderson <rth@twiddle.net>
Signed-off-by: default avatarEduardo Habkost <ehabkost@redhat.com>
parent 9646f492

target-i386/cpu.c

+16 −10
Original line number Diff line number Diff line
@@ -2490,7 +2490,6 @@ void cpu_x86_cpuid(CPUX86State *env, uint32_t index, uint32_t count, 
        *ebx &= 0xffff; /* The count doesn't need to be reliable. */

        break;

    case 0xD: {

        KVMState *s = cs->kvm_state;

        uint64_t ena_mask;

        int i;
@@ -2502,20 +2501,28 @@ void cpu_x86_cpuid(CPUX86State *env, uint32_t index, uint32_t count, 
        if (!(env->features[FEAT_1_ECX] & CPUID_EXT_XSAVE)) {

            break;

        }



        ena_mask = (XSTATE_FP_MASK | XSTATE_SSE_MASK);

        for (i = 2; i < ARRAY_SIZE(x86_ext_save_areas); i++) {

            const ExtSaveArea *esa = &x86_ext_save_areas[i];

            if (env->features[esa->feature] & esa->bits) {

                ena_mask |= (1ULL << i);

            }

        }



        if (kvm_enabled()) {

            ena_mask = kvm_arch_get_supported_cpuid(s, 0xd, 0, R_EDX);

            ena_mask <<= 32;

            ena_mask |= kvm_arch_get_supported_cpuid(s, 0xd, 0, R_EAX);

        } else {

            ena_mask = -1;

            KVMState *s = cs->kvm_state;

            uint64_t kvm_mask = kvm_arch_get_supported_cpuid(s, 0xd, 0, R_EDX);

            kvm_mask <<= 32;

            kvm_mask |= kvm_arch_get_supported_cpuid(s, 0xd, 0, R_EAX);

            ena_mask &= kvm_mask;

        }



        if (count == 0) {

            *ecx = 0x240;

            for (i = 2; i < ARRAY_SIZE(x86_ext_save_areas); i++) {

                const ExtSaveArea *esa = &x86_ext_save_areas[i];

                if ((env->features[esa->feature] & esa->bits)

                    && ((ena_mask >> i) & 1) != 0) {

                if ((ena_mask >> i) & 1) {

                    if (i < 32) {

                        *eax |= 1u << i;

                    } else {
@@ -2530,8 +2537,7 @@ void cpu_x86_cpuid(CPUX86State *env, uint32_t index, uint32_t count, 
            *eax = env->features[FEAT_XSAVE];

        } else if (count < ARRAY_SIZE(x86_ext_save_areas)) {

            const ExtSaveArea *esa = &x86_ext_save_areas[count];

            if ((env->features[esa->feature] & esa->bits)

                && ((ena_mask >> count) & 1) != 0) {

            if ((ena_mask >> count) & 1) {

                *eax = esa->size;

                *ebx = esa->offset;

            }