[FLA] Introduce Kimi Delta Attention(KDA) to VLLM#27654
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youkaichao merged 2 commits intovllm-project:mainfrom Oct 28, 2025
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[FLA] Introduce Kimi Delta Attention(KDA) to VLLM#27654youkaichao merged 2 commits intovllm-project:mainfrom
youkaichao merged 2 commits intovllm-project:mainfrom
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Signed-off-by: lizhiyuan <lizhiyuan@moonshot.cn>
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This pull request introduces Kimi Delta Attention (KDA) into vLLM by adding new kernels and modifying existing ones. The changes are extensive and add a significant new feature. I have identified a couple of critical bugs related to incorrect tensor shapes and memory strides in the Triton kernels, which could lead to incorrect outputs. Additionally, there's a performance-related issue in the autotuning configuration of one of the kernels. Addressing these points will be crucial for the correctness and efficiency of the new implementation.
| num_stages = 3 | ||
| num_warps = 1 | ||
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| o = torch.empty_like(k) |
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The output tensor o is being allocated with the shape of the key tensor k (torch.empty_like(k)). However, the output of an attention operation should have the shape of the value tensor v. The shape of k is [B, T, H, K] while v is [B, T, HV, V], which can be different. This will lead to a shape mismatch and incorrect output. Please allocate o with the shape of v.
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| o = torch.empty_like(k) | |
| o = torch.empty_like(v) |
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In KDA models, q, k, v, and o share the same shape, so it's safe to use empty_like(k).
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youkaichao
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looking forward to the new model 👍
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ilmarkov
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Signed-off-by: lizhiyuan <lizhiyuan@moonshot.cn>
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Signed-off-by: lizhiyuan <lizhiyuan@moonshot.cn>
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Signed-off-by: lizhiyuan <lizhiyuan@moonshot.cn>
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### What this PR does / why we need it? adapt vllm-ascend main branch with vllm releases/v0.11.1 fix `forward context not set` in test_vlm.py caused by: vllm-project/vllm#23207 fix import `cdiv round` failed caused by: vllm-project/vllm#27188 fix import `init_cached_hf_modules` failed caused by: vllm-project/vllm#27567 adapt triton kernel `fused_recurrent_gated_delta_rule_fwd_kernel` caused by: vllm-project/vllm#27654 - remove unused code in sigmoid_gating.py - `class FusedRecurrentFunction` , `fused_recurrent_gated_delta_rule`, `fused_recurrent_gated_delta_rule_fwd` ### Does this PR introduce _any_ user-facing change? No ### How was this patch tested? CI - vLLM version: v0.11.0 - vLLM main: vllm-project/vllm@83f478b Signed-off-by: 22dimensions <waitingwind@foxmail.com>
luolun
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### What this PR does / why we need it? adapt vllm-ascend main branch with vllm releases/v0.11.1 fix `forward context not set` in test_vlm.py caused by: vllm-project/vllm#23207 fix import `cdiv round` failed caused by: vllm-project/vllm#27188 fix import `init_cached_hf_modules` failed caused by: vllm-project/vllm#27567 adapt triton kernel `fused_recurrent_gated_delta_rule_fwd_kernel` caused by: vllm-project/vllm#27654 - remove unused code in sigmoid_gating.py - `class FusedRecurrentFunction` , `fused_recurrent_gated_delta_rule`, `fused_recurrent_gated_delta_rule_fwd` ### Does this PR introduce _any_ user-facing change? No ### How was this patch tested? CI - vLLM version: v0.11.0 - vLLM main: vllm-project/vllm@83f478b Signed-off-by: 22dimensions <waitingwind@foxmail.com> Signed-off-by: luolun <luolun1995@cmbchina.com>
hwhaokun
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### What this PR does / why we need it? adapt vllm-ascend main branch with vllm releases/v0.11.1 fix `forward context not set` in test_vlm.py caused by: vllm-project/vllm#23207 fix import `cdiv round` failed caused by: vllm-project/vllm#27188 fix import `init_cached_hf_modules` failed caused by: vllm-project/vllm#27567 adapt triton kernel `fused_recurrent_gated_delta_rule_fwd_kernel` caused by: vllm-project/vllm#27654 - remove unused code in sigmoid_gating.py - `class FusedRecurrentFunction` , `fused_recurrent_gated_delta_rule`, `fused_recurrent_gated_delta_rule_fwd` ### Does this PR introduce _any_ user-facing change? No ### How was this patch tested? CI - vLLM version: v0.11.0 - vLLM main: vllm-project/vllm@83f478b Signed-off-by: 22dimensions <waitingwind@foxmail.com> Signed-off-by: hwhaokun <haokun0405@163.com>
NSDie
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Nov 24, 2025
### What this PR does / why we need it? adapt vllm-ascend main branch with vllm releases/v0.11.1 fix `forward context not set` in test_vlm.py caused by: vllm-project/vllm#23207 fix import `cdiv round` failed caused by: vllm-project/vllm#27188 fix import `init_cached_hf_modules` failed caused by: vllm-project/vllm#27567 adapt triton kernel `fused_recurrent_gated_delta_rule_fwd_kernel` caused by: vllm-project/vllm#27654 - remove unused code in sigmoid_gating.py - `class FusedRecurrentFunction` , `fused_recurrent_gated_delta_rule`, `fused_recurrent_gated_delta_rule_fwd` ### Does this PR introduce _any_ user-facing change? No ### How was this patch tested? CI - vLLM version: v0.11.0 - vLLM main: vllm-project/vllm@83f478b Signed-off-by: 22dimensions <waitingwind@foxmail.com> Signed-off-by: nsdie <yeyifan@huawei.com>
devpatelio
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Signed-off-by: lizhiyuan <lizhiyuan@moonshot.cn>
Clorist33
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Dec 10, 2025
### What this PR does / why we need it? adapt vllm-ascend main branch with vllm releases/v0.11.1 fix `forward context not set` in test_vlm.py caused by: vllm-project/vllm#23207 fix import `cdiv round` failed caused by: vllm-project/vllm#27188 fix import `init_cached_hf_modules` failed caused by: vllm-project/vllm#27567 adapt triton kernel `fused_recurrent_gated_delta_rule_fwd_kernel` caused by: vllm-project/vllm#27654 - remove unused code in sigmoid_gating.py - `class FusedRecurrentFunction` , `fused_recurrent_gated_delta_rule`, `fused_recurrent_gated_delta_rule_fwd` ### Does this PR introduce _any_ user-facing change? No ### How was this patch tested? CI - vLLM version: v0.11.0 - vLLM main: vllm-project/vllm@83f478b Signed-off-by: 22dimensions <waitingwind@foxmail.com>
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