diff --git a/docs/system/arm/emulation.rst b/docs/system/arm/emulation.rst
index b12f013..4e8aca8 100644
--- a/docs/system/arm/emulation.rst
+++ b/docs/system/arm/emulation.rst
@@ -89,6 +89,7 @@
 - FEAT_LRCPC2 (Load-acquire RCpc instructions v2)
 - FEAT_LSE (Large System Extensions)
 - FEAT_LSE2 (Large System Extensions v2)
+- FEAT_LSE128 (128-bit Atomics)
 - FEAT_LVA (Large Virtual Address space)
 - FEAT_MixedEnd (Mixed-endian support)
 - FEAT_MixedEndEL0 (Mixed-endian support at EL0)
diff --git a/linux-user/aarch64/elfload.c b/linux-user/aarch64/elfload.c
index 8bf39c4..77d03b5 100644
--- a/linux-user/aarch64/elfload.c
+++ b/linux-user/aarch64/elfload.c
@@ -216,6 +216,7 @@
     GET_FEATURE_ID(aa64_sme_f16f16, ARM_HWCAP2_A64_SME_F16F16);
     GET_FEATURE_ID(aa64_sve_b16b16, ARM_HWCAP2_A64_SVE_B16B16);
     GET_FEATURE_ID(aa64_cssc, ARM_HWCAP2_A64_CSSC);
+    GET_FEATURE_ID(aa64_lse128, ARM_HWCAP2_A64_LSE128);
 
     return hwcaps;
 }
diff --git a/target/arm/tcg/cpu64.c b/target/arm/tcg/cpu64.c
index eaf8846..b8b1981 100644
--- a/target/arm/tcg/cpu64.c
+++ b/target/arm/tcg/cpu64.c
@@ -1145,7 +1145,7 @@
     t = FIELD_DP64(t, ID_AA64ISAR0, SHA1, 1);     /* FEAT_SHA1 */
     t = FIELD_DP64(t, ID_AA64ISAR0, SHA2, 2);     /* FEAT_SHA512 */
     t = FIELD_DP64(t, ID_AA64ISAR0, CRC32, 1);    /* FEAT_CRC32 */
-    t = FIELD_DP64(t, ID_AA64ISAR0, ATOMIC, 2);   /* FEAT_LSE */
+    t = FIELD_DP64(t, ID_AA64ISAR0, ATOMIC, 3);   /* FEAT_LSE, FEAT_LSE128 */
     t = FIELD_DP64(t, ID_AA64ISAR0, RDM, 1);      /* FEAT_RDM */
     t = FIELD_DP64(t, ID_AA64ISAR0, SHA3, 1);     /* FEAT_SHA3 */
     t = FIELD_DP64(t, ID_AA64ISAR0, SM3, 1);      /* FEAT_SM3 */