From ab0f4cedc3554f921691ce5b63d59e258154e799 Mon Sep 17 00:00:00 2001 From: David Gow Date: Wed, 5 Jun 2024 06:40:50 +0800 Subject: arch: um: rust: Add i386 support for Rust At present, Rust in the kernel only supports 64-bit x86, so UML has followed suit. However, it's significantly easier to support 32-bit i386 on UML than on bare metal, as UML does not use the -mregparm option (which alters the ABI), which is not yet supported by rustc[1]. Add support for CONFIG_RUST on um/i386, by adding a new target config to generate_rust_target, and replacing various checks on CONFIG_X86_64 to also support CONFIG_X86_32. We still use generate_rust_target, rather than a built-in rustc target, in order to match x86_64, provide a future place for -mregparm, and more easily disable floating point instructions. With these changes, the KUnit tests pass with: kunit.py run --make_options LLVM=1 --kconfig_add CONFIG_RUST=y --kconfig_add CONFIG_64BIT=n --kconfig_add CONFIG_FORTIFY_SOURCE=n An earlier version of these changes was proposed on the Rust-for-Linux github[2]. [1]: https://github.com/rust-lang/rust/issues/116972 [2]: https://github.com/Rust-for-Linux/linux/pull/966 Signed-off-by: David Gow Link: https://patch.msgid.link/20240604224052.3138504-1-davidgow@google.com Signed-off-by: Johannes Berg --- rust/Makefile | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'rust') diff --git a/rust/Makefile b/rust/Makefile index f70d5e244fee..83f675adbfab 100644 --- a/rust/Makefile +++ b/rust/Makefile @@ -426,7 +426,7 @@ $(obj)/core.o: private rustc_objcopy = $(foreach sym,$(redirect-intrinsics),--re $(obj)/core.o: private rustc_target_flags = $(core-cfgs) $(obj)/core.o: $(RUST_LIB_SRC)/core/src/lib.rs FORCE +$(call if_changed_dep,rustc_library) -ifdef CONFIG_X86_64 +ifneq ($(or $(CONFIG_X86_64),$(CONFIG_X86_32)),) $(obj)/core.o: scripts/target.json endif -- cgit v1.2.3-70-g09d2