diff --git a/target/arm/cpu64.c b/target/arm/cpu64.c index eb9318c83b..557fd47577 100644 --- a/target/arm/cpu64.c +++ b/target/arm/cpu64.c @@ -265,14 +265,17 @@ void arm_cpu_sve_finalize(ARMCPU *cpu, Error **errp) * any of the above. Finally, if SVE is not disabled, then at least one * vector length must be enabled. */ - DECLARE_BITMAP(kvm_supported, ARM_MAX_VQ); DECLARE_BITMAP(tmp, ARM_MAX_VQ); uint32_t vq, max_vq = 0; - /* Collect the set of vector lengths supported by KVM. */ - bitmap_zero(kvm_supported, ARM_MAX_VQ); + /* + * CPU models specify a set of supported vector lengths which are + * enabled by default. Attempting to enable any vector length not set + * in the supported bitmap results in an error. When KVM is enabled we + * fetch the supported bitmap from the host. + */ if (kvm_enabled() && kvm_arm_sve_supported()) { - kvm_arm_sve_get_vls(CPU(cpu), kvm_supported); + kvm_arm_sve_get_vls(CPU(cpu), cpu->sve_vq_supported); } else if (kvm_enabled()) { assert(!cpu_isar_feature(aa64_sve, cpu)); } @@ -299,7 +302,7 @@ void arm_cpu_sve_finalize(ARMCPU *cpu, Error **errp) * For KVM we have to automatically enable all supported unitialized * lengths, even when the smaller lengths are not all powers-of-two. */ - bitmap_andnot(tmp, kvm_supported, cpu->sve_vq_init, max_vq); + bitmap_andnot(tmp, cpu->sve_vq_supported, cpu->sve_vq_init, max_vq); bitmap_or(cpu->sve_vq_map, cpu->sve_vq_map, tmp, max_vq); } else { /* Propagate enabled bits down through required powers-of-two. */ @@ -322,12 +325,12 @@ void arm_cpu_sve_finalize(ARMCPU *cpu, Error **errp) /* Disabling a supported length disables all larger lengths. */ for (vq = 1; vq <= ARM_MAX_VQ; ++vq) { if (test_bit(vq - 1, cpu->sve_vq_init) && - test_bit(vq - 1, kvm_supported)) { + test_bit(vq - 1, cpu->sve_vq_supported)) { break; } } max_vq = vq <= ARM_MAX_VQ ? vq - 1 : ARM_MAX_VQ; - bitmap_andnot(cpu->sve_vq_map, kvm_supported, + bitmap_andnot(cpu->sve_vq_map, cpu->sve_vq_supported, cpu->sve_vq_init, max_vq); if (max_vq == 0 || bitmap_empty(cpu->sve_vq_map, max_vq)) { error_setg(errp, "cannot disable sve%d", vq * 128); @@ -392,7 +395,7 @@ void arm_cpu_sve_finalize(ARMCPU *cpu, Error **errp) if (kvm_enabled()) { /* Ensure the set of lengths matches what KVM supports. */ - bitmap_xor(tmp, cpu->sve_vq_map, kvm_supported, max_vq); + bitmap_xor(tmp, cpu->sve_vq_map, cpu->sve_vq_supported, max_vq); if (!bitmap_empty(tmp, max_vq)) { vq = find_last_bit(tmp, max_vq) + 1; if (test_bit(vq - 1, cpu->sve_vq_map)) {