Commit 09498135 authored by Miguel Ojeda's avatar Miguel Ojeda
Browse files

x86: enable initial Rust support 



Note that only x86_64 is covered and not all features nor mitigations
are handled, but it is enough as a starting point and showcases
the basics needed to add Rust support for a new architecture.

Reviewed-by: default avatarKees Cook <keescook@chromium.org>
Reviewed-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Co-developed-by: default avatarAlex Gaynor <alex.gaynor@gmail.com>
Signed-off-by: default avatarAlex Gaynor <alex.gaynor@gmail.com>
Co-developed-by: default avatarWedson Almeida Filho <wedsonaf@google.com>
Signed-off-by: default avatarWedson Almeida Filho <wedsonaf@google.com>
Co-developed-by: default avatarDavid Gow <davidgow@google.com>
Signed-off-by: default avatarDavid Gow <davidgow@google.com>
Signed-off-by: default avatarMiguel Ojeda <ojeda@kernel.org>
parent d07479b2

Documentation/rust/arch-support.rst

+1 −0
Original line number Diff line number Diff line
@@ -15,4 +15,5 @@ support corresponds to ``S`` values in the ``MAINTAINERS`` file. 
============  ================  ==============================================

Architecture  Level of support  Constraints

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

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

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

arch/x86/Kconfig

+1 −0
Original line number Diff line number Diff line
@@ -257,6 +257,7 @@ config X86 
	select HAVE_STATIC_CALL_INLINE		if HAVE_OBJTOOL

	select HAVE_PREEMPT_DYNAMIC_CALL

	select HAVE_RSEQ

	select HAVE_RUST			if X86_64

	select HAVE_SYSCALL_TRACEPOINTS

	select HAVE_UACCESS_VALIDATION		if HAVE_OBJTOOL

	select HAVE_UNSTABLE_SCHED_CLOCK

arch/x86/Makefile

+10 −0
Original line number Diff line number Diff line
@@ -68,6 +68,7 @@ export BITS 
#    https://gcc.gnu.org/bugzilla/show_bug.cgi?id=53383

#

KBUILD_CFLAGS += -mno-sse -mno-mmx -mno-sse2 -mno-3dnow -mno-avx

KBUILD_RUSTFLAGS += -Ctarget-feature=-sse,-sse2,-sse3,-ssse3,-sse4.1,-sse4.2,-avx,-avx2



ifeq ($(CONFIG_X86_KERNEL_IBT),y)

#
@@ -155,8 +156,17 @@ else 
        cflags-$(CONFIG_GENERIC_CPU)	+= -mtune=generic

        KBUILD_CFLAGS += $(cflags-y)



        rustflags-$(CONFIG_MK8)		+= -Ctarget-cpu=k8

        rustflags-$(CONFIG_MPSC)	+= -Ctarget-cpu=nocona

        rustflags-$(CONFIG_MCORE2)	+= -Ctarget-cpu=core2

        rustflags-$(CONFIG_MATOM)	+= -Ctarget-cpu=atom

        rustflags-$(CONFIG_GENERIC_CPU)	+= -Ztune-cpu=generic

        KBUILD_RUSTFLAGS += $(rustflags-y)



        KBUILD_CFLAGS += -mno-red-zone

        KBUILD_CFLAGS += -mcmodel=kernel

        KBUILD_RUSTFLAGS += -Cno-redzone=y

        KBUILD_RUSTFLAGS += -Ccode-model=kernel

endif



#

scripts/generate_rust_target.rs

+13 −2
Original line number Diff line number Diff line
@@ -148,8 +148,19 @@ fn main() { 
    let mut ts = TargetSpec::new();



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

    if cfg.has("DUMMY_ARCH") {

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

    if cfg.has("X86_64") {

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

        ts.push(

            "data-layout",

            "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128",

        );

        let mut features = "-3dnow,-3dnowa,-mmx,+soft-float".to_string();

        if cfg.has("RETPOLINE") {

            features += ",+retpoline-external-thunk";

        }

        ts.push("features", features);

        ts.push("llvm-target", "x86_64-linux-gnu");

        ts.push("target-pointer-width", "64");

    } else {

        panic!("Unsupported architecture");

    }