[CI/Build][CPU] Remove global extra index (#47687)

Signed-off-by: jiang1.li <jiang1.li@intel.com>

docker/Dockerfile.cpu

@@ -25,7 +25,6 @@ FROM ubuntu:22.04 AS base-common
 WORKDIR /workspace
 
 ARG PYTHON_VERSION=3.12
-ARG PIP_EXTRA_INDEX_URL="https://download.pytorch.org/whl/cpu"
 
 ARG max_jobs=32
 ENV MAX_JOBS=${max_jobs}
@@ -53,8 +52,6 @@ ENV PATH="$VIRTUAL_ENV/bin:$PATH"
 ENV UV_HTTP_TIMEOUT=500
 
 # Install Python dependencies
-ENV PIP_EXTRA_INDEX_URL=${PIP_EXTRA_INDEX_URL}
-ENV UV_EXTRA_INDEX_URL=${PIP_EXTRA_INDEX_URL}
 ENV UV_INDEX_STRATEGY="unsafe-best-match"
 ENV UV_LINK_MODE="copy"
 
@@ -64,7 +61,7 @@ COPY requirements/cpu.txt requirements/cpu.txt
 
 RUN --mount=type=cache,target=/root/.cache/uv \
     uv pip install --upgrade pip && \
-    uv pip install -r requirements/cpu.txt
+    uv pip install -r requirements/cpu.txt --torch-backend cpu
 
 ARG TARGETARCH
 ENV TARGETARCH=${TARGETARCH}
@@ -149,7 +146,7 @@ RUN if [ "$TARGETARCH" = "arm64" ] && [ "$VLLM_CPU_X86" != "0" ]; then \
 COPY requirements/build/cpu.txt requirements/build/cpu.txt
 
 RUN --mount=type=cache,target=/root/.cache/uv \
-    uv pip install -r requirements/build/cpu.txt
+    uv pip install -r requirements/build/cpu.txt --torch-backend cpu
 
 COPY . .
 
@@ -205,7 +202,7 @@ RUN case "$(uname -m)" in \
     esac
 
 RUN --mount=type=cache,target=/root/.cache/uv \
-    uv pip install -r requirements/test/cpu.txt
+    uv pip install -r requirements/test/cpu.txt --torch-backend cpu
 
 ######################### DEV IMAGE #########################
 FROM vllm-build AS vllm-dev
@@ -231,7 +228,7 @@ COPY --from=vllm-test-deps /vllm-workspace/requirements/test/cpu.txt requirement
 
 RUN --mount=type=cache,target=/root/.cache/uv \
     uv pip install -r requirements/lint.txt && \
-    uv pip install -r requirements/test/cpu.txt && \
+    uv pip install -r requirements/test/cpu.txt --torch-backend cpu && \
     pre-commit install --hook-type pre-commit --hook-type commit-msg
 
 ENTRYPOINT ["bash"]

docker/Dockerfile.s390x

@@ -249,7 +249,7 @@ RUN --mount=type=cache,target=/root/.cache/uv \
      NUMBA_WHL_FILE=$(ls /tmp/numba-wheels/*.whl) && \
      OPENCV_WHL_FILE=$(ls /tmp/opencv-wheels/*.whl) && \
      GUIDANCE_WHL_FILE=$(ls /tmp/guidance-wheels/*.whl) && \
-     uv pip install -v \    
+     uv pip install -v \
         $ARROW_WHL_FILE \
         $VISION_WHL_FILE \
         $HF_XET_WHL_FILE \
@@ -257,6 +257,7 @@ RUN --mount=type=cache,target=/root/.cache/uv \
         $NUMBA_WHL_FILE \
         $OPENCV_WHL_FILE \
         $GUIDANCE_WHL_FILE \
+        --torch-backend cpu \
         --index-strategy unsafe-best-match \
         -r requirements/build/cpu.txt \
         -r requirements/cpu.txt

docs/getting_started/installation/cpu.apple.inc.md

@@ -35,15 +35,10 @@ After installation of XCode and the Command Line Tools, which include Apple Clan
 ```bash
 git clone https://github.com/vllm-project/vllm.git
 cd vllm
-uv pip install -r requirements/cpu.txt --index-strategy unsafe-best-match
+uv pip install -r requirements/cpu.txt
 uv pip install -e .
 ```
 
-!!! tip
-    The `--index-strategy unsafe-best-match` flag is needed to resolve dependencies across multiple package indexes (PyTorch CPU index and PyPI). Without this flag, you may encounter `typing-extensions` version conflicts.
-
-    The term "unsafe" refers to the package resolution strategy, not security. By default, `uv` only searches the first index where a package is found to prevent dependency confusion attacks. This flag allows `uv` to search all configured indexes to find the best compatible versions. Since both PyTorch and PyPI are trusted package sources, using this strategy is safe and appropriate for vLLM installation.
-
 !!! note
     On macOS the `VLLM_TARGET_DEVICE` is automatically set to `cpu`, which is currently the only supported device.
 

docs/getting_started/installation/cpu.s390x.inc.md

@@ -48,10 +48,10 @@ Execute the following commands to build and install vLLM from source.
 
 ```bash
     uv pip install -v \
-        --extra-index-url https://download.pytorch.org/whl/cpu \
-        --torch-backend auto \
         -r requirements/build/cpu.txt \
         -r requirements/cpu.txt \
+        --torch-backend cpu \
+        --index-strategy unsafe-best-match && \
     VLLM_TARGET_DEVICE=cpu python setup.py bdist_wheel && \
         uv pip install dist/*.whl
 ```

requirements/build/cpu.txt

@@ -1,4 +1,3 @@
---extra-index-url https://download.pytorch.org/whl/cpu
 cmake>=3.26.1
 ninja
 packaging>=24.2

requirements/cpu.txt

@@ -1,4 +1,3 @@
---extra-index-url https://download.pytorch.org/whl/cpu
 # Common dependencies
 -r common.txt