diff options
| author |  David Gow <davidgow@google.com>
| 2022-12-17 12:44:35 +0800 |
|---|---|---|
| committer |  Richard Weinberger <richard@nod.at>
| 2023-02-10 21:28:25 +0100 |
| commit | 8849818679478933dd1d9718741f4daa3f4e8b86 (patch) | |
| tree | 9cf7727eca7cb8ea2993909f1eace565aae8f56f | |
| parent | rust: arch/um: Use 'pie' relocation mode under UML (diff) | |
| download | linux-8849818679478933dd1d9718741f4daa3f4e8b86.tar.gz linux-8849818679478933dd1d9718741f4daa3f4e8b86.tar.bz2 linux-8849818679478933dd1d9718741f4daa3f4e8b86.zip | |
rust: arch/um: Disable FP/SIMD instruction to match x86
The kernel disables all SSE and similar FP/SIMD instructions on
x86-based architectures (partly because we shouldn't be using floats in
the kernel, and partly to avoid the need for stack alignment, see:
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=53383 )
UML does not do the same thing, which isn't in itself a problem, but
does add to the list of differences between UML and "normal" x86 builds.
In addition, there was a crash bug with LLVM < 15 / rustc < 1.65 when
building with SSE, so disabling it fixes rust builds with earlier
compiler versions, see:
https://github.com/Rust-for-Linux/linux/pull/881
Signed-off-by: David Gow <davidgow@google.com>
Reviewed-by: Sergio González Collado <sergio.collado@gmail.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
| -rw-r--r-- | arch/x86/Makefile.um | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/arch/x86/Makefile.um b/arch/x86/Makefile.um index b3c1ae084180..d2e95d1d4db7 100644 --- a/arch/x86/Makefile.um +++ b/arch/x86/Makefile.um @@ -1,6 +1,12 @@ # SPDX-License-Identifier: GPL-2.0 core-y += arch/x86/crypto/ +# +# Disable SSE and other FP/SIMD instructions to match normal x86 +# +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_32),y) START := 0x8048000 |