`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.

Similarly, do so for Rust host programs too.

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 # non-hostprogs Tested-by: Andrea Righi andrea.righi@canonical.com # non-hostprogs Fixes: 295d8398c67e ("kbuild: specify output names separately for each emission type from rustc") Cc: stable@vger.kernel.org Signed-off-by: Miguel Ojeda ojeda@kernel.org --- v2: - Add fix for host programs too (Masahiro).

scripts/Makefile.build | 5 ++++- scripts/Makefile.host | 6 +++++- 2 files changed, 9 insertions(+), 2 deletions(-)

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 diff --git a/scripts/Makefile.host b/scripts/Makefile.host index 7aea9005e497..8f7f842b54f9 100644 --- a/scripts/Makefile.host +++ b/scripts/Makefile.host @@ -86,7 +86,11 @@ hostc_flags = -Wp,-MMD,$(depfile) \ hostcxx_flags = -Wp,-MMD,$(depfile) \ $(KBUILD_HOSTCXXFLAGS) $(HOST_EXTRACXXFLAGS) \ $(HOSTCXXFLAGS_$(target-stem).o) -hostrust_flags = --emit=dep-info=$(depfile) \ + +# `--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. +hostrust_flags = --out-dir $(dir $@) --emit=dep-info=$(depfile) \ $(KBUILD_HOSTRUSTFLAGS) $(HOST_EXTRARUSTFLAGS) \ $(HOSTRUSTFLAGS_$(target-stem))

base-commit: 06c2afb862f9da8dc5efa4b6076a0e48c3fbaaa5