kernel/scripts/is_rust_module.sh, branch 0x221E-v0.0-v7.0

btf, scripts: rust: drop is_rust_module.sh

2023-08-10T20:28:04Z

With commit c1177979af9c ("btf, scripts: Exclude Rust CUs with pahole") we are now able to use pahole directly to identify Rust compilation units (CUs) and exclude them from generating BTF debugging information (when DEBUG_INFO_BTF is enabled). And if pahole doesn't support the --lang-exclude flag, we can't enable both RUST and DEBUG_INFO_BTF at the same time. So, in any case, the script is_rust_module.sh is just redundant and we can drop it. NOTE: we may also be able to drop the "Rust loadable module" mark inside Rust modules, but it seems safer to keep it for now to make sure we are not breaking any external tool that may potentially rely on it. Signed-off-by: Andrea Righi Reviewed-by: Nathan Chancellor Tested-by: Eric Curtin Reviewed-by: Eric Curtin Reviewed-by: Neal Gompa Reviewed-by: Masahiro Yamada Reviewed-by: Martin Rodriguez Reboredo Acked-by: Daniel Xu Link: https://lore.kernel.org/r/20230704052136.155445-1-andrea.righi@canonical.com [ Picked the `Reviewed-by`s from the old patch too. ] Signed-off-by: Miguel Ojeda

rust: fix regexp in scripts/is_rust_module.sh

2023-04-19T17:28:49Z

nm can use "R" or "r" to show read-only data sections, but scripts/is_rust_module.sh can only recognize "r", so with some versions of binutils it can fail to detect if a module is a Rust module or not. Right now we're using this script only to determine if we need to skip BTF generation (that is disabled globally if CONFIG_RUST is enabled), but it's still nice to fix this script to do the proper job. Moreover, with this patch applied I can also relax the constraint of "RUST depends on !DEBUG_INFO_BTF" and build a kernel with Rust and BTF enabled at the same time (of course BTF generation is still skipped for Rust modules). [ Miguel: The actual reason is likely to be a change on the Rust compiler between 1.61.0 and 1.62.0: echo '#[used] static S: () = ();' | rustup run 1.61.0 rustc --emit=obj --crate-type=lib - && nm rust_out.o echo '#[used] static S: () = ();' | rustup run 1.62.0 rustc --emit=obj --crate-type=lib - && nm rust_out.o Gives: 0000000000000000 r _ZN8rust_out1S17h48027ce0da975467E 0000000000000000 R _ZN8rust_out1S17h58e1f3d9c0e97cefE See https://godbolt.org/z/KE6jneoo4. ] Signed-off-by: Andrea Righi Reviewed-by: Vincenzo Palazzo Reviewed-by: Eric Curtin Reviewed-by: Martin Rodriguez Reboredo Signed-off-by: Miguel Ojeda

scripts: add `is_rust_module.sh`

2022-09-28T07:02:06Z

This script is used to detect whether a kernel module is written in Rust. It will later be used to disable BTF generation on Rust modules as BTF does not yet support Rust. Reviewed-by: Kees Cook Reviewed-by: Greg Kroah-Hartman Co-developed-by: Alex Gaynor Signed-off-by: Alex Gaynor Co-developed-by: Wedson Almeida Filho Signed-off-by: Wedson Almeida Filho Signed-off-by: Daniel Xu Co-developed-by: Miguel Ojeda Signed-off-by: Miguel Ojeda