[RFC PATCH 2/2] kbuild: rust: use klint to provide CONFIG_FRAME_WARN
From: Gary Guo <gary@kernel.org>
Date: 2026-01-27 17:23:59
Also in:
linux-kbuild, lkml
Subsystem:
kernel build + files below scripts/ (unless maintained elsewhere), the rest · Maintainers:
Nathan Chancellor, Nicolas Schier, Linus Torvalds
From: Gary Guo <gary@garyguo.net>
klint is able to analyze frame size and warn on frames that are too big.
With `register_tool(klint)` support, we can simply instruct rust to turn on
`klint::stack_frame_too_large`. This is a no-op if normal rustc (or Clippy)
is invoked, but will perform the check if klint is used.
This is an example of a bug caught using this option:
warning: stack size of `gsp::cmdq::Cmdq::new` is 8216 bytes, exceeds the 2048-byte limit
--> drivers/gpu/nova-core/gsp/cmdq.rs:453:5
|
453 | pub(crate) fn new(dev: &device::Device<device::Bound>) -> Result<Cmdq> {
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
= note: the stack size is inferred from instruction `sub $0x2018,%rsp` at .text+32778
Signed-off-by: Gary Guo <gary@garyguo.net>
---
scripts/Makefile.warn | 1 +
1 file changed, 1 insertion(+)
diff --git a/scripts/Makefile.warn b/scripts/Makefile.warn
index 5567da6c7dfe..254a4d53f8f3 100644
--- a/scripts/Makefile.warn
+++ b/scripts/Makefile.warn@@ -23,6 +23,7 @@ KBUILD_CFLAGS += -Wmissing-prototypes ifneq ($(CONFIG_FRAME_WARN),0) KBUILD_CFLAGS += -Wframe-larger-than=$(CONFIG_FRAME_WARN) +KBUILD_RUSTFLAGS += -Wklint::stack-frame-too-large endif KBUILD_CFLAGS-$(CONFIG_CC_NO_ARRAY_BOUNDS) += -Wno-array-bounds
--
2.51.2