[AMD][Kernel][Bugfix] Cast offsets tensor bn to tl.int64 to avoid GPU segfault #23692
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Signed-off-by: Randall Smith <Randall.Smith@amd.com>
…libi Signed-off-by: Randall Smith <Randall.Smith@amd.com>
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This pull request correctly addresses a critical integer overflow in the _fwd_kernel for AMD GPUs by casting the bn tensor to tl.int64, which prevents a potential GPU segfault. However, as noted in the pull request description, similar vulnerabilities exist in _fwd_kernel_flash_attn_v2 and _fwd_kernel_alibi. The fixes for these functions are currently missing from the patch. It is crucial to include these changes to ensure the bug is fully resolved across all relevant kernels.
jatseng-ai
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Aug 27, 2025
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Aug 28, 2025
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* 'main' of https://github.com/845473182/vllm: (457 commits) [BugFix] Fix routed_scaling_factor double mul for dots1 and glm4 MoE models (vllm-project#24132) [Misc] Add check for dual_chunk_attention (vllm-project#24070) [Doc]: fix typos in Python comments (vllm-project#24115) [Doc]: fix typos in Python comments (vllm-project#24093) [Compile] Fix Compile Warning for `w4a8_mm_entry.cu` (vllm-project#23660) fix some typos (vllm-project#24071) [V1] Wrapper which plumbs request-level logits processors into vLLM batch-level logits processing (vllm-project#23656) Upgrade xgrammar to 0.1.23 (vllm-project#22988) Update release pipeline post PyTorch 2.8.0 update (vllm-project#24073) [XPU] Fix the bug of LoRA logits on the XPU platform (vllm-project#24081) [CI/Build] Disable SiluMul NVFP4 quant fusion tests (vllm-project#24121) [Bug] R1 Accuracy: Fix `routed_scaling_factor` Double Mul Issue (vllm-project#24119) [AMD][Kernel][Bugfix] Cast offsets tensor bn to tl.int64 to avoid GPU segfault (vllm-project#23692) [CI] Enable all hf transformers baselines in test_hybrid (vllm-project#23936) [Log] Only Print Profiler Results on Rank 0 (vllm-project#23370) Fix weights loading for Apertus (vllm-project#24100) [Metrics] Deprecate TPOT in favor of ITL (vllm-project#24110) [Bugfix] Fix packed_factor missing attribute error (vllm-project#23902) Run ruff format on a few files. (vllm-project#24075) [Bugfix] Fix transform_config parsing in Compressed Tensors (vllm-project#23945) ...
eicherseiji
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… segfault (vllm-project#23692) Signed-off-by: Randall Smith <Randall.Smith@amd.com>
FeiDaLI
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… segfault (vllm-project#23692) Signed-off-by: Randall Smith <Randall.Smith@amd.com>
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The tensor loaded into
bnis multiplied bystride_k_cache_bsin the_fwd_kernelinprefix_prefill.pyand produces an integer overflow resulting in negative offsets which result in a GPU segfault. Changingstride_k_cache_bsto betl.int64in the function signature did not work. Casting thebntensor totl.int64fixes the problem. I added some additional casts into_fwd_kernel_flash_attn_v2and_fwd_kernel_alibias well.