docs: rust: document ppc64le RUST_OPT_LEVEL_0/1 restrictions

Mention that RUST_OPT_LEVEL_0/1 require increasing the kernel stack
size.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
[normalized title]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>

diff --git a/Documentation/rust/arch-support.rst b/Documentation/rust/arch-support.rst
index ce6025ad558b6568fb36e16913ce45b1b5073aa9..e93a8ceb3f82d937226f69c3e73426bca3488619 100644 (file)
--- a/Documentation/rust/arch-support.rst
+++ b/Documentation/rust/arch-support.rst
@@ -26,7 +26,7 @@ support corresponds to ``S`` values in the ``MAINTAINERS`` file.
      - None
    * - ``powerpc``
      - Maintained
-     - ``ppc64le`` only, ``RUST_OPT_LEVEL >= 2``
+     - ``ppc64le`` only, ``RUST_OPT_LEVEL < 2`` requires ``CONFIG_THREAD_SHIFT=15``
    * - ``x86``
      - Maintained
      - ``x86_64`` only