CUDA: fix MMQ stream-k rounding if ne00 % 128 != 0 (#8311)

Author: JohannesGaessler

ggml/src/ggml-cuda/mmq.cuh

@@ -2305,8 +2305,11 @@ static __global__ void mul_mat_q(
     const int nty = (ne01 + mmq_y - 1) / mmq_y; // Number of tiles y
 
     // kbc == k block continuous, current index in continuous ijk space.
-    int64_t       kbc      = GGML_PAD((int64_t) blockIdx.x     *blocks_per_ne00*ntx*nty / gridDim.x, blocks_per_warp);
-    const int64_t kbc_stop = GGML_PAD((int64_t)(blockIdx.x + 1)*blocks_per_ne00*ntx*nty / gridDim.x, blocks_per_warp);
+    int64_t kbc      = (int64_t) blockIdx.x     *blocks_per_ne00*ntx*nty / gridDim.x;
+    int64_t kbc_stop = (int64_t)(blockIdx.x + 1)*blocks_per_ne00*ntx*nty / gridDim.x;
+
+    kbc      -= (kbc      % blocks_per_ne00) % blocks_per_warp;
+    kbc_stop -= (kbc_stop % blocks_per_ne00) % blocks_per_warp;
 
     // kb0 == k index when doing the matrix multiplication for an output tile.
     int kb0_start = kbc % blocks_per_ne00;
@@ -2362,8 +2365,11 @@ static __global__ void mul_mat_q_stream_k_fixup(
     const int bidx_stop  = (blockIdx.y*nty + blockIdx.x + 1) * block_num_mmq / (gridDim.y*gridDim.x) + 1;
 
     for (int bidx = bidx_start; bidx < bidx_stop; ++bidx) {
-        const int64_t kbc      = GGML_PAD((int64_t) bidx     *blocks_per_ne00*ntx*nty / block_num_mmq, blocks_per_warp);
-        const int64_t kbc_stop = GGML_PAD((int64_t)(bidx + 1)*blocks_per_ne00*ntx*nty / block_num_mmq, blocks_per_warp);
+        int64_t kbc      = (int64_t) bidx     *blocks_per_ne00*ntx*nty / block_num_mmq;
+        int64_t kbc_stop = (int64_t)(bidx + 1)*blocks_per_ne00*ntx*nty / block_num_mmq;
+
+        kbc      -= (kbc      % blocks_per_ne00) % blocks_per_warp;
+        kbc_stop -= (kbc_stop % blocks_per_ne00) % blocks_per_warp;
 
         // Skip fixup tile if the MMQ CUDA block never wrote anything to it:
         if (kbc == kbc_stop || kbc_stop % blocks_per_ne00 == 0) {