On 2/5/2025 5:28 PM, Markus Armbruster wrote:
Xiaoyao Li <xiaoyao.li@xxxxxxxxx> writes:Use KVM_TDX_GET_CPUID to get the CPUIDs that are managed and enfored by TDX module for TD guest. Check QEMU's configuration against the fetched data. Print wanring message when 1. a feature is not supported but requested by QEMU or 2. QEMU doesn't want to expose a feature while it is enforced enabled. - If cpu->enforced_cpuid is not set, prints the warning message of both 1) and 2) and tweak QEMU's configuration. - If cpu->enforced_cpuid is set, quit if any case of 1) or 2). Signed-off-by: Xiaoyao Li <xiaoyao.li@xxxxxxxxx> --- target/i386/cpu.c | 33 ++++++++++++++- target/i386/cpu.h | 7 +++ target/i386/kvm/tdx.c | 99 +++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 137 insertions(+), 2 deletions(-) diff --git a/target/i386/cpu.c b/target/i386/cpu.c index f1330627adbb..a948fd0bd674 100644 --- a/target/i386/cpu.c +++ b/target/i386/cpu.c @@ -5482,8 +5482,8 @@ static bool x86_cpu_have_filtered_features(X86CPU *cpu) return false; }-static void mark_unavailable_features(X86CPU *cpu, FeatureWord w, uint64_t mask,- const char *verbose_prefix) +void mark_unavailable_features(X86CPU *cpu, FeatureWord w, uint64_t mask, + const char *verbose_prefix) { CPUX86State *env = &cpu->env; FeatureWordInfo *f = &feature_word_info[w]; @@ -5510,6 +5510,35 @@ static void mark_unavailable_features(X86CPU *cpu, FeatureWord w, uint64_t mask, } }+void mark_forced_on_features(X86CPU *cpu, FeatureWord w, uint64_t mask,+ const char *verbose_prefix) +{ + CPUX86State *env = &cpu->env; + FeatureWordInfo *f = &feature_word_info[w]; + int i; + + if (!cpu->force_features) { + env->features[w] |= mask; + } + + cpu->forced_on_features[w] |= mask; + + if (!verbose_prefix) { + return; + } + + for (i = 0; i < 64; ++i) { + if ((1ULL << i) & mask) { + g_autofree char *feat_word_str = feature_word_description(f);Does not compile for me: ../target/i386/cpu.c: In function ‘mark_forced_on_features’: ../target/i386/cpu.c:5531:46: error: too few arguments to function ‘feature_word_description’ 5531 | g_autofree char *feat_word_str = feature_word_description(f); | ^~~~~~~~~~~~~~~~~~~~~~~~ ../target/i386/cpu.c:5451:14: note: declared here 5451 | static char *feature_word_description(FeatureWordInfo *f, uint32_t bit) | ^~~~~~~~~~~~~~~~~~~~~~~~
As mentioned in the cover letter, this series depends on a minor one: https://lore.kernel.org/qemu-devel/20241217123932.948789-1-xiaoyao.li@xxxxxxxxx/
+ warn_report("%s: %s%s%s [bit %d]", + verbose_prefix, + feat_word_str, + f->feat_names[i] ? "." : "", + f->feat_names[i] ? f->feat_names[i] : "", i); + } + } +} + static void x86_cpuid_version_get_family(Object *obj, Visitor *v, const char *name, void *opaque, Error **errp)[...]
