Commit 724a75ac authored by Jamie Cunliffe's avatar Jamie Cunliffe Committed by Catalin Marinas
Browse files

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.

Signed-off-by: default avatarJamie Cunliffe <Jamie.Cunliffe@arm.com>
Acked-by: default avatarWill Deacon <will@kernel.org>
Tested-by: default avatarDirk Behme <dirk.behme@de.bosch.com>
Tested-by: default avatarBoqun Feng <boqun.feng@gmail.com>
Acked-by: default avatarMiguel Ojeda <ojeda@kernel.org>
Acked-by: default avatarCatalin Marinas <catalin.marinas@arm.com>
Tested-by: default avatarAlice Ryhl <aliceryhl@google.com>
Tested-by: default avatarFabien Parent <fabien.parent@linaro.org>
Link: https://lore.kernel.org/r/20231020155056.3495121-3-Jamie.Cunliffe@arm.com


Signed-off-by: default avatarCatalin Marinas <catalin.marinas@arm.com>
parent f82811e2

Documentation/rust/arch-support.rst

+1 −0
Original line number Diff line number Diff line
@@ -15,6 +15,7 @@ support corresponds to ``S`` values in the ``MAINTAINERS`` file. 
=============  ================  ==============================================

Architecture   Level of support  Constraints

=============  ================  ==============================================

``arm64``      Maintained        Little Endian only.

``loongarch``  Maintained        -

``um``         Maintained        ``x86_64`` only.

``x86``        Maintained        ``x86_64`` only.

arch/arm64/Kconfig

+1 −0
Original line number Diff line number Diff line
@@ -229,6 +229,7 @@ config ARM64 
	select HAVE_FUNCTION_ARG_ACCESS_API

	select MMU_GATHER_RCU_TABLE_FREE

	select HAVE_RSEQ

	select HAVE_RUST if CPU_LITTLE_ENDIAN

	select HAVE_STACKPROTECTOR

	select HAVE_SYSCALL_TRACEPOINTS

	select HAVE_KPROBES

arch/arm64/Makefile

+4 −0
Original line number Diff line number Diff line
@@ -41,6 +41,8 @@ KBUILD_CFLAGS += -mgeneral-regs-only \ 
KBUILD_CFLAGS	+= $(call cc-disable-warning, psabi)

KBUILD_AFLAGS	+= $(compat_vdso)



KBUILD_RUSTFLAGS += --target=aarch64-unknown-none -Ctarget-feature="-neon"



KBUILD_CFLAGS	+= $(call cc-option,-mabi=lp64)

KBUILD_AFLAGS	+= $(call cc-option,-mabi=lp64)
@@ -65,7 +67,9 @@ endif 


ifeq ($(CONFIG_ARM64_BTI_KERNEL),y)

  KBUILD_CFLAGS += -mbranch-protection=pac-ret+bti

  KBUILD_RUSTFLAGS += -Zbranch-protection=bti,pac-ret

else ifeq ($(CONFIG_ARM64_PTR_AUTH_KERNEL),y)

  KBUILD_RUSTFLAGS += -Zbranch-protection=pac-ret

  ifeq ($(CONFIG_CC_HAS_BRANCH_PROT_PAC_RET),y)

    KBUILD_CFLAGS += -mbranch-protection=pac-ret

  else

rust/Makefile

+1 −0
Original line number Diff line number Diff line
@@ -297,6 +297,7 @@ bindgen_skip_c_flags := -mno-fp-ret-in-387 -mpreferred-stack-boundary=% \ 


# Derived from `scripts/Makefile.clang`.

BINDGEN_TARGET_x86	:= x86_64-linux-gnu

BINDGEN_TARGET_arm64	:= aarch64-linux-gnu

BINDGEN_TARGET		:= $(BINDGEN_TARGET_$(SRCARCH))



# All warnings are inhibited since GCC builds are very experimental,

scripts/generate_rust_target.rs

+3 −1
Original line number Diff line number Diff line
@@ -148,7 +148,9 @@ fn main() { 
    let mut ts = TargetSpec::new();



    // `llvm-target`s are taken from `scripts/Makefile.clang`.

    if cfg.has("X86_64") {

    if cfg.has("ARM64") {

        panic!("arm64 uses the builtin rustc aarch64-unknown-none target");

    } else if cfg.has("X86_64") {

        ts.push("arch", "x86_64");

        ts.push(

            "data-layout",