On 11/5/2024 5:12 PM, Paolo Bonzini wrote:
On 11/5/24 07:24, Xiaoyao Li wrote:
Otherwise, it gets warnings like below when number of vcpus > 1:
warning: TDX enforces set the feature: CPUID.01H:EDX.ht [bit 28]
This is because x86_confidential_guest_check_features() checks
env->features[] instead of the cpuid date set up by cpu_x86_cpuid()
Signed-off-by: Xiaoyao Li <xiaoyao.li@xxxxxxxxx>
---
target/i386/cpu.c | 11 ++++++++++-
1 file changed, 10 insertions(+), 1 deletion(-)
diff --git a/target/i386/cpu.c b/target/i386/cpu.c
index 472ab206d8fe..214a1b00a815 100644
--- a/target/i386/cpu.c
+++ b/target/i386/cpu.c
@@ -6571,7 +6571,6 @@ void cpu_x86_cpuid(CPUX86State *env, uint32_t
index, uint32_t count,
*edx = env->features[FEAT_1_EDX];
if (threads_per_pkg > 1) {
*ebx |= threads_per_pkg << 16;
- *edx |= CPUID_HT;
}
if (!cpu->enable_pmu) {
*ecx &= ~CPUID_EXT_PDCM;
@@ -7784,6 +7783,8 @@ static void x86_cpu_realizefn(DeviceState *dev,
Error **errp)
Error *local_err = NULL;
unsigned requested_lbr_fmt;
+ qemu_early_init_vcpu(cs);
+
#if defined(CONFIG_TCG) && !defined(CONFIG_USER_ONLY)
/* Use pc-relative instructions in system-mode */
tcg_cflags_set(cs, CF_PCREL);
@@ -7851,6 +7852,14 @@ static void x86_cpu_realizefn(DeviceState *dev,
Error **errp)
}
}
+ /*
+ * It needs to called after feature filter because KVM doesn't
report HT
+ * as supported
Does it, since kvm_arch_get_supported_cpuid() has the following line?
if (function == 1 && reg == R_EDX) {
...
/* KVM never reports CPUID_HT but QEMU can support when vcpus >
1 */
ret |= CPUID_HT;
?
It seems I mixed it up with no_autoenable_flags. /faceplam
CPUID_HT doesn't get enabled by x86_cpu_expand_features() for "-cpu
host/max". It won't be filtered by x86_cpu_filter_features() either
because QEMU sets it in kvm_arch_get_supported_cpuid().
yes, the comment is wrong and comment needs to be dropped. The code can
be move up to just below x86_cpu_expand_features() or inside it?
Paolo
+ */
+ if (cs->nr_cores * cs->nr_threads > 1) {
+ env->features[FEAT_1_EDX] |= CPUID_HT;
+ }
