On Tue, Jul 18, 2023 at 2:52 PM Miguel Ojeda ojeda@kernel.org wrote:
`rustc` outputs by default the temporary files (i.e. the ones saved by `-Csave-temps`, such as `*.rcgu*` files) in the current working directory when `-o` and `--out-dir` are not given (even if `--emit=x=path` is given, i.e. it does not use those for temporaries).
Since out-of-tree modules are compiled from the `linux` tree, `rustc` then tries to create them there, which may not be accessible.
Thus pass `--out-dir` explicitly, even if it is just for the temporary files.
Reported-by: Raphael Nestler raphael.nestler@gmail.com Closes: https://github.com/Rust-for-Linux/linux/issues/1015 Reported-by: Andrea Righi andrea.righi@canonical.com Tested-by: Raphael Nestler raphael.nestler@gmail.com Tested-by: Andrea Righi andrea.righi@canonical.com Cc: stable@vger.kernel.org Signed-off-by: Miguel Ojeda ojeda@kernel.org
Applied to linux-kbuild/fixes. Thanks.
I believe this is a fix, so I will include it in my next pull request.
scripts/Makefile.build | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/scripts/Makefile.build b/scripts/Makefile.build index 6413342a03f4..82e3fb19fdaf 100644 --- a/scripts/Makefile.build +++ b/scripts/Makefile.build @@ -264,6 +264,9 @@ $(obj)/%.lst: $(src)/%.c FORCE
rust_allowed_features := new_uninit
+# `--out-dir` is required to avoid temporaries being created by `rustc` in the +# current working directory, which may be not accessible in the out-of-tree +# modules case. rust_common_cmd = \ RUST_MODFILE=$(modfile) $(RUSTC_OR_CLIPPY) $(rust_flags) \ -Zallow-features=$(rust_allowed_features) \ @@ -272,7 +275,7 @@ rust_common_cmd = \ --extern alloc --extern kernel \ --crate-type rlib -L $(objtree)/rust/ \ --crate-name $(basename $(notdir $@)) \
--emit=dep-info=$(depfile)
--out-dir $(dir $@) --emit=dep-info=$(depfile)# `--emit=obj`, `--emit=asm` and `--emit=llvm-ir` imply a single codegen unit # will be used. We explicitly request `-Ccodegen-units=1` in any case, and
base-commit: 06c2afb862f9da8dc5efa4b6076a0e48c3fbaaa5
2.41.0