diff mbox series

[v5,3/3] i386: Add support for overflow recovery

Message ID 20240603193622.47156-4-john.allen@amd.com (mailing list archive)
State New
Headers show
Series Fix MCE handling on AMD hosts | expand

Commit Message

John Allen June 3, 2024, 7:36 p.m. UTC 
Add cpuid bit definition for overflow recovery. This is needed in the case
where a deferred error has been sent to the guest, a guest process accesses the
poisoned memory, but the machine_check_poll function has not yet handled the
original deferred error. If overflow recovery is not set in this case, when we
handle the uncorrected error from the poisoned memory access, the overflow bit
will be set and will result in the guest being shut down.

Signed-off-by: John Allen <john.allen@amd.com>
---
v5:
  - New in v5.
---
 target/i386/cpu.c     | 2 +-
 target/i386/cpu.h     | 1 +
 target/i386/kvm/kvm.c | 2 +-
 3 files changed, 3 insertions(+), 2 deletions(-)
diff mbox series

Patch

diff --git a/target/i386/cpu.c b/target/i386/cpu.c
index 5fa2dde732..5385b26d4a 100644
--- a/target/i386/cpu.c
+++ b/target/i386/cpu.c
@@ -1035,7 +1035,7 @@  FeatureWordInfo feature_word_info[FEATURE_WORDS] = {
     [FEAT_8000_0007_EBX] = {
         .type = CPUID_FEATURE_WORD,
         .feat_names = {
-            NULL, "succor", NULL, NULL,
+            "overflow-recov", "succor", NULL, NULL,
             NULL, NULL, NULL, NULL,
             NULL, NULL, NULL, NULL,
             NULL, NULL, NULL, NULL,
diff --git a/target/i386/cpu.h b/target/i386/cpu.h
index 5dd41e3d69..d56cf631b5 100644
--- a/target/i386/cpu.h
+++ b/target/i386/cpu.h
@@ -955,6 +955,7 @@  uint64_t x86_cpu_get_supported_feature_word(FeatureWord w,
 #define CPUID_14_0_ECX_LIP              (1U << 31)
 
 /* RAS Features */
+#define CPUID_8000_0007_EBX_OVERFLOW_RECOV    (1U << 0)
 #define CPUID_8000_0007_EBX_SUCCOR      (1U << 1)
 
 /* CLZERO instruction */
diff --git a/target/i386/kvm/kvm.c b/target/i386/kvm/kvm.c
index 384b702fef..796d5e9e38 100644
--- a/target/i386/kvm/kvm.c
+++ b/target/i386/kvm/kvm.c
@@ -477,7 +477,7 @@  uint32_t kvm_arch_get_supported_cpuid(KVMState *s, uint32_t function,
         cpuid_1_edx = kvm_arch_get_supported_cpuid(s, 1, 0, R_EDX);
         ret |= cpuid_1_edx & CPUID_EXT2_AMD_ALIASES;
     } else if (function == 0x80000007 && reg == R_EBX) {
-        ret |= CPUID_8000_0007_EBX_SUCCOR;
+        ret |= CPUID_8000_0007_EBX_OVERFLOW_RECOV | CPUID_8000_0007_EBX_SUCCOR;
     } else if (function == KVM_CPUID_FEATURES && reg == R_EAX) {
         /* kvm_pv_unhalt is reported by GET_SUPPORTED_CPUID, but it can't
          * be enabled without the in-kernel irqchip