6.6-stable review patch. If anyone has any objections, please let me know.
------------------
From: Matthew Maurer <mmaurer@xxxxxxxxxx>
commit 5daa0c35a1f0e7a6c3b8ba9cb721e7d1ace6e619 upstream.
The kernel cannot currently self-parse BTF containing Rust debug
information. pahole uses the language of the CU to determine whether to
filter out debug information when generating the BTF. When LTO is
enabled, Rust code can cross CU boundaries, resulting in Rust debug
information in CUs labeled as C. This results in a system which cannot
parse its own BTF.
Signed-off-by: Matthew Maurer <mmaurer@xxxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
Fixes: c1177979af9c ("btf, scripts: Exclude Rust CUs with pahole")
Link: https://lore.kernel.org/r/20250108-rust-btf-lto-incompat-v1-1-60243ff6d820@xxxxxxxxxx
Signed-off-by: Miguel Ojeda <ojeda@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
init/Kconfig | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/init/Kconfig
+++ b/init/Kconfig
@@ -1908,7 +1908,7 @@ config RUST
depends on !GCC_PLUGINS
depends on !RANDSTRUCT
depends on !SHADOW_CALL_STACK
- depends on !DEBUG_INFO_BTF || PAHOLE_HAS_LANG_EXCLUDE
+ depends on !DEBUG_INFO_BTF || (PAHOLE_HAS_LANG_EXCLUDE && !LTO)
help
Enables Rust support in the kernel.
