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A high-throughput and memory-efficient inference and serving engine for LLMs

Mirrored from https://github.com/tduncan-lum/Nvidia-Optimization-Stack---VLLM.git

Synced Nov 14, 05:30 UTC

Quick fix for IMA with the Prefix Prefill kernel during graph capture (#25983)

Signed-off-by: Sage Moore <sage@neuralmagic.com>

Sage Moore committed Oct 3, 2025 at 04:28 UTC 5f2cacdb1e62e468c707eab168c6d6961254bc93
1 file changed +8
vllm/v1/attention/backends/rocm_attn.py
+8
@@ -83,6 +83,14 @@ class RocmAttentionMetadataBuilder(
83 # max_model_len will cause graph capture to be extremely
84 # slow, so here we set it to 1.
85 attn_metadata.seq_lens.fill_(1)
86 +
87 + if envs.VLLM_V1_USE_PREFILL_DECODE_ATTENTION:
88 + # Here we set the query start locs to 0. This is to
89 + # cover up an invalid memory access in the prefix_prefil kernel
90 + # that we run into during graph capture (#25985)
91 + common_attn_metadata.query_start_loc.zero_()
92 + common_attn_metadata.query_start_loc_cpu.zero_()
93 +
94 return attn_metadata
95
96 def build(self,