arm64: rust: Enable Rust support for AArch64

This commit provides the build flags for Rust for AArch64. The core Rust support already in the kernel does the rest. This enables the PAC ret and BTI options in the Rust build flags to match the options that are used when building C. The Rust samples have been tested with this commit.

Jamie Cunliffe committed 3 years ago

Commit 724a75a1 parent f82811e5 files · +10 −1Browse files

Unified · Split

5 files

Documentation/rust/arch-support.rst +1 −0
arch/arm64/Kconfig +1 −0
arch/arm64/Makefile +4 −0
rust/Makefile +1 −0
scripts/generate_rust_target.rs +3 −1

Documentation/rust/arch-support.rst+1−0

@@ -15,6 +15,7 @@ support corresponds to ``S`` values in the ``MAINTAINERS`` file. · 14 unmodified lines
15	15	============= ================ ==============================================
16	16	Architecture Level of support Constraints
17	17	============= ================ ==============================================
	18	+``arm64`` Maintained Little Endian only.
18	19	``loongarch`` Maintained -
19	20	``um`` Maintained ``x86_64`` only.
20	21	``x86`` Maintained ``x86_64`` only.

arch/arm64/Kconfig+1−0

@@ -229,6 +229,7 @@ config ARM64 · 228 unmodified lines
229	229	select HAVE_FUNCTION_ARG_ACCESS_API
230	230	select MMU_GATHER_RCU_TABLE_FREE
231	231	select HAVE_RSEQ
	232	+ select HAVE_RUST if CPU_LITTLE_ENDIAN
232	233	select HAVE_STACKPROTECTOR
233	234	select HAVE_SYSCALL_TRACEPOINTS
234	235	select HAVE_KPROBES

arch/arm64/Makefile+4−0

@@ -41,6 +41,8 @@ KBUILD_CFLAGS += -mgeneral-regs-only \ · 40 unmodified lines
41	41	KBUILD_CFLAGS += $(call cc-disable-warning, psabi)
42	42	KBUILD_AFLAGS += $(compat_vdso)
43	43
	44	+KBUILD_RUSTFLAGS += --target=aarch64-unknown-none -Ctarget-feature="-neon"
	45	+
44	46	KBUILD_CFLAGS += $(call cc-option,-mabi=lp64)
45	47	KBUILD_AFLAGS += $(call cc-option,-mabi=lp64)
46	48
@@ -65,7 +67,9 @@ endif · 18 unmodified lines
65	67
66	68	ifeq ($(CONFIG_ARM64_BTI_KERNEL),y)
67	69	KBUILD_CFLAGS += -mbranch-protection=pac-ret+bti
	70	+ KBUILD_RUSTFLAGS += -Zbranch-protection=bti,pac-ret
68	71	else ifeq ($(CONFIG_ARM64_PTR_AUTH_KERNEL),y)
	72	+ KBUILD_RUSTFLAGS += -Zbranch-protection=pac-ret
69	73	ifeq ($(CONFIG_CC_HAS_BRANCH_PROT_PAC_RET),y)
70	74	KBUILD_CFLAGS += -mbranch-protection=pac-ret
71	75	else

rust/Makefile+1−0

@@ -297,6 +297,7 @@ bindgen_skip_c_flags := -mno-fp-ret-in-387 -mpreferred-stack-boundary=% \ · 296 unmodified lines
297	297
298	298	# Derived from `scripts/Makefile.clang`.
299	299	BINDGEN_TARGET_x86 := x86_64-linux-gnu
	300	+BINDGEN_TARGET_arm64 := aarch64-linux-gnu
300	301	BINDGEN_TARGET := $(BINDGEN_TARGET_$(SRCARCH))
301	302
302	303	# All warnings are inhibited since GCC builds are very experimental,

scripts/generate_rust_target.rs+3−1

@@ -148,7 +148,9 @@ fn main() { · 147 unmodified lines
148	148	let mut ts = TargetSpec::new();
149	149
150	150	// `llvm-target`s are taken from `scripts/Makefile.clang`.
151		− if cfg.has("X86_64") {
	151	+ if cfg.has("ARM64") {
	152	+ panic!("arm64 uses the builtin rustc aarch64-unknown-none target");
	153	+ } else if cfg.has("X86_64") {
152	154	ts.push("arch", "x86_64");
153	155	ts.push(
154	156	"data-layout",