ggml-org/llama.cpp b11047

on GitHub

cuda : fix CUB argsort corruption caused by in-place keys (#28389)

argsort_f32_i32_cuda_cub called the one-shot DeviceRadixSort::SortPairs
API with d_keys_in == d_keys_out (temp_keys, temp_keys). CUB's internal
double-buffer ping-pong requires distinct key buffers: with aliased
buffers the sort partially overwrites its own input mid-pass and emits a
corrupted permutation, surfacing as intermittent garbage indices (e.g.
backend top_k over a 248k-column vocab on Maxwell/CUDA 12.5/CCCL 2.x,
which then triggered out-of-bounds gathers in downstream get_rows).

Use a distinct keys-out buffer for all six call sites (plain and
segmented, ascending and descending, size-query and execute).

Co-authored-by: Claude Opus 4.6 noreply@anthropic.com
Co-authored-by: Oliver Simons osimons@nvidia.com