Bus lock debug exception is a feature that can notify the kernel by
generate an #DB trap after the instruction acquires a bus lock when
CPL>0. This allows the kernel to enforce user application throttling or
mitigations.
This feature is enumerated via CPUID.(EAX=7,ECX=0).ECX[bit 24].
Signed-off-by: Chenyi Qiang <chenyi.qiang@intel.com>
---
target/i386/cpu.c | 2 +-
target/i386/cpu.h | 2 ++
2 files changed, 3 insertions(+), 1 deletion(-)
diff --git a/target/i386/cpu.c b/target/i386/cpu.c
index ae89024d36..55f3b5829f 100644
--- a/target/i386/cpu.c
+++ b/target/i386/cpu.c
@@ -963,7 +963,7 @@ static FeatureWordInfo feature_word_info[FEATURE_WORDS] = {
"avx512bitalg", NULL, "avx512-vpopcntdq", NULL,
"la57", NULL, NULL, NULL,
NULL, NULL, "rdpid", NULL,
- NULL, "cldemote", NULL, "movdiri",
+ "bus-lock-detect", "cldemote", NULL, "movdiri",
"movdir64b", NULL, NULL, NULL,
},
.cpuid = {
diff --git a/target/i386/cpu.h b/target/i386/cpu.h
index d23a5b340a..417f49b721 100644
--- a/target/i386/cpu.h
+++ b/target/i386/cpu.h
@@ -762,6 +762,8 @@ typedef uint64_t FeatureWordArray[FEATURE_WORDS];
#define CPUID_7_0_ECX_LA57 (1U << 16)
/* Read Processor ID */
#define CPUID_7_0_ECX_RDPID (1U << 22)
+/* Bus Lock Debug Exception */
+#define CPUID_7_0_ECX_BUS_LOCK_DETECT (1U << 24)
/* Cache Line Demote Instruction */
#define CPUID_7_0_ECX_CLDEMOTE (1U << 25)
/* Move Doubleword as Direct Store Instruction */