diff --git a/vllm/attention/backends/utils.py b/vllm/attention/backends/utils.py
index 33d8168f8a13c..63ee8f50825c5 100644
--- a/vllm/attention/backends/utils.py
+++ b/vllm/attention/backends/utils.py
@@ -18,11 +18,6 @@ from vllm.utils import async_tensor_h2d, make_tensor_with_pad
 
 logger = init_logger(__name__)
 
-# Error string(s) for encoder/decoder
-# unsupported attention scenarios
-STR_NOT_IMPL_ENC_DEC_ROCM_HIP = ("ROCm/HIP is not currently supported "
-                                 "with encoder/decoder models.")
-
 PAD_SLOT_ID = -1
 
 # Switch to numpy implementation of compute_slot_mapping
diff --git a/vllm/utils/__init__.py b/vllm/utils/__init__.py
index 834ec9b1d30b4..b74b746a35830 100644
--- a/vllm/utils/__init__.py
+++ b/vllm/utils/__init__.py
@@ -88,64 +88,6 @@ DEFAULT_MAX_NUM_BATCHED_TOKENS = 2048
 POOLING_MODEL_MAX_NUM_BATCHED_TOKENS = 32768
 MULTIMODAL_MODEL_MAX_NUM_BATCHED_TOKENS = 5120
 
-# Exception strings for non-implemented encoder/decoder scenarios
-
-# Reminder: Please update docs/features/compatibility_matrix.md
-# If the feature combo become valid
-
-STR_NOT_IMPL_ENC_DEC_SWA = \
-    "Sliding window attention for encoder/decoder models " + \
-    "is not currently supported."
-
-STR_NOT_IMPL_ENC_DEC_PREFIX_CACHE = \
-    "Prefix caching for encoder/decoder models " + \
-    "is not currently supported."
-
-STR_NOT_IMPL_ENC_DEC_CHUNKED_PREFILL = \
-    "Chunked prefill for encoder/decoder models " + \
-    "is not currently supported."
-
-STR_NOT_IMPL_ENC_DEC_LOGIT_SOFTCAP = (
-    "Models with logits_soft_cap "
-    "require FlashInfer backend, which is "
-    "currently not supported for encoder/decoder "
-    "models.")
-
-STR_NOT_IMPL_ENC_DEC_LORA = ("LoRA is not currently "
-                             "supported with encoder/decoder "
-                             "models.")
-
-STR_NOT_IMPL_ENC_DEC_PP = ("Pipeline parallelism is not "
-                           "currently supported with "
-                           "encoder/decoder models.")
-
-STR_NOT_IMPL_ENC_DEC_MM = ("Multimodal is not currently "
-                           "supported with encoder/decoder "
-                           "models.")
-
-STR_NOT_IMPL_ENC_DEC_SPEC_DEC = ("Speculative decoding is not "
-                                 "currently supported with encoder/"
-                                 "decoder models.")
-
-STR_NOT_IMPL_ENC_DEC_BACKEND = ("XFormers and Flash-Attention are the only "
-                                "backends currently supported with encoder/"
-                                "decoder models.")
-
-# Efficiently import all enc/dec error strings
-# rather than having to import all of the above
-STR_NOT_IMPL_ENC_DEC_ERR_STRS = {
-    "STR_NOT_IMPL_ENC_DEC_SWA": STR_NOT_IMPL_ENC_DEC_SWA,
-    "STR_NOT_IMPL_ENC_DEC_PREFIX_CACHE": STR_NOT_IMPL_ENC_DEC_PREFIX_CACHE,
-    "STR_NOT_IMPL_ENC_DEC_CHUNKED_PREFILL":
-    STR_NOT_IMPL_ENC_DEC_CHUNKED_PREFILL,
-    "STR_NOT_IMPL_ENC_DEC_LOGIT_SOFTCAP": STR_NOT_IMPL_ENC_DEC_LOGIT_SOFTCAP,
-    "STR_NOT_IMPL_ENC_DEC_LORA": STR_NOT_IMPL_ENC_DEC_LORA,
-    "STR_NOT_IMPL_ENC_DEC_PP": STR_NOT_IMPL_ENC_DEC_PP,
-    "STR_NOT_IMPL_ENC_DEC_MM": STR_NOT_IMPL_ENC_DEC_MM,
-    "STR_NOT_IMPL_ENC_DEC_SPEC_DEC": STR_NOT_IMPL_ENC_DEC_SPEC_DEC,
-    "STR_NOT_IMPL_ENC_DEC_BACKEND": STR_NOT_IMPL_ENC_DEC_BACKEND,
-}
-
 # Constants related to forcing the attention backend selection
 
 # String name of register which may be set in order to