target/i386: Add more features enumerated by CPUID.7.2.EDX

Following 5 bits in CPUID.7.2.EDX are supported by KVM. Add their
supports in QEMU. Each of them indicates certain bits of IA32_SPEC_CTRL
are supported. Those bits can control CPU speculation behavior which can
be used to defend against side-channel attacks.

bit0: intel-psfd
  if 1, indicates bit 7 of the IA32_SPEC_CTRL MSR is supported. Bit 7 of
  this MSR disables Fast Store Forwarding Predictor without disabling
  Speculative Store Bypass

bit1: ipred-ctrl
  If 1, indicates bits 3 and 4 of the IA32_SPEC_CTRL MSR are supported.
  Bit 3 of this MSR enables IPRED_DIS control for CPL3. Bit 4 of this
  MSR enables IPRED_DIS control for CPL0/1/2

bit2: rrsba-ctrl
  If 1, indicates bits 5 and 6 of the IA32_SPEC_CTRL MSR are supported.
  Bit 5 of this MSR disables RRSBA behavior for CPL3. Bit 6 of this MSR
  disables RRSBA behavior for CPL0/1/2

bit3: ddpd-u
  If 1, indicates bit 8 of the IA32_SPEC_CTRL MSR is supported. Bit 8 of
  this MSR disables Data Dependent Prefetcher.

bit4: bhi-ctrl
  if 1, indicates bit 10 of the IA32_SPEC_CTRL MSR is supported. Bit 10
  of this MSR enables BHI_DIS_S behavior.

Signed-off-by: Chao Gao <chao.gao@intel.com>
Link: https://lore.kernel.org/r/20240919051011.118309-1-chao.gao@intel.com
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

diff --git a/target/i386/cpu.c b/target/i386/cpu.c
index 5535f4e6ab47b989d43a33f08064b6f1542c7351..9a6b9e9e51b16df670ae19282724ab002c05073d 100644 (file)
--- a/target/i386/cpu.c
+++ b/target/i386/cpu.c
@@ -1148,8 +1148,8 @@ FeatureWordInfo feature_word_info[FEATURE_WORDS] = {
     [FEAT_7_2_EDX] = {
         .type = CPUID_FEATURE_WORD,
         .feat_names = {
-            NULL, NULL, NULL, NULL,
-            NULL, "mcdt-no", NULL, NULL,
+            "intel-psfd", "ipred-ctrl", "rrsba-ctrl", "ddpd-u",
+            "bhi-ctrl", "mcdt-no", NULL, NULL,
             NULL, NULL, NULL, NULL,
             NULL, NULL, NULL, NULL,
             NULL, NULL, NULL, NULL,