diff mbox series

[PULL,05/25] target/i386: Add more features enumerated by CPUID.7.2.EDX

Message ID 20241015141711.528342-6-pbonzini@redhat.com (mailing list archive)
State New, archived
Headers show
Series [PULL,01/25] target/i386: Don't construct a all-zero entry for CPUID[0xD 0x3f] | expand

Commit Message

Paolo Bonzini Oct. 15, 2024, 2:16 p.m. UTC 
From: Chao Gao <chao.gao@intel.com>

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>
---
 target/i386/cpu.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)
diff mbox series

Patch

diff --git a/target/i386/cpu.c b/target/i386/cpu.c
index 5535f4e6ab4..9a6b9e9e51b 100644
--- 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,