The patch titled
Subject: selftests/fpu: allow building on other architectures
has been added to the -mm mm-nonmm-unstable branch. Its filename is
selftests-fpu-allow-building-on-other-architectures.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/selftests-fpu-allow-building-on-other-architectures.patch
This patch will later appear in the mm-nonmm-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
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------------------------------------------------------
From: Samuel Holland <samuel.holland@xxxxxxxxxx>
Subject: selftests/fpu: allow building on other architectures
Date: Wed, 27 Mar 2024 13:00:45 -0700
Now that ARCH_HAS_KERNEL_FPU_SUPPORT provides a common way to compile
and run floating-point code, this test is no longer x86-specific.
Link: https://lkml.kernel.org/r/20240327200157.1097089-15-samuel.holland@xxxxxxxxxx
Signed-off-by: Samuel Holland <samuel.holland@xxxxxxxxxx>
Reviewed-by: Christoph Hellwig <hch@xxxxxx>
Cc: Alex Deucher <alexander.deucher@xxxxxxx>
Cc: Borislav Petkov (AMD) <bp@xxxxxxxxx>
Cc: Catalin Marinas <catalin.marinas@xxxxxxx>
Cc: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx>
Cc: Huacai Chen <chenhuacai@xxxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: Jonathan Corbet <corbet@xxxxxxx>
Cc: Masahiro Yamada <masahiroy@xxxxxxxxxx>
Cc: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
Cc: Nathan Chancellor <nathan@xxxxxxxxxx>
Cc: Nicolas Schier <nicolas@xxxxxxxxx>
Cc: Palmer Dabbelt <palmer@xxxxxxxxxxxx>
Cc: Russell King <linux@xxxxxxxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: WANG Xuerui <git@xxxxxxxxxx>
Cc: Will Deacon <will@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
lib/Kconfig.debug | 2 +-
lib/Makefile | 25 ++-----------------------
lib/test_fpu_glue.c | 5 ++++-
3 files changed, 7 insertions(+), 25 deletions(-)
--- a/lib/Kconfig.debug~selftests-fpu-allow-building-on-other-architectures
+++ a/lib/Kconfig.debug
@@ -2921,7 +2921,7 @@ config TEST_FREE_PAGES
config TEST_FPU
tristate "Test floating point operations in kernel space"
- depends on X86 && !KCOV_INSTRUMENT_ALL
+ depends on ARCH_HAS_KERNEL_FPU_SUPPORT && !KCOV_INSTRUMENT_ALL
help
Enable this option to add /sys/kernel/debug/selftest_helpers/test_fpu
which will trigger a sequence of floating point operations. This is used
--- a/lib/Makefile~selftests-fpu-allow-building-on-other-architectures
+++ a/lib/Makefile
@@ -110,31 +110,10 @@ CFLAGS_test_fprobe.o += $(CC_FLAGS_FTRAC
obj-$(CONFIG_FPROBE_SANITY_TEST) += test_fprobe.o
obj-$(CONFIG_TEST_OBJPOOL) += test_objpool.o
-#
-# CFLAGS for compiling floating point code inside the kernel. x86/Makefile turns
-# off the generation of FPU/SSE* instructions for kernel proper but FPU_FLAGS
-# get appended last to CFLAGS and thus override those previous compiler options.
-#
-FPU_CFLAGS := -msse -msse2
-ifdef CONFIG_CC_IS_GCC
-# Stack alignment mismatch, proceed with caution.
-# GCC < 7.1 cannot compile code using `double` and -mpreferred-stack-boundary=3
-# (8B stack alignment).
-# See https://gcc.gnu.org/bugzilla/show_bug.cgi?id=53383
-#
-# The "-msse" in the first argument is there so that the
-# -mpreferred-stack-boundary=3 build error:
-#
-# -mpreferred-stack-boundary=3 is not between 4 and 12
-#
-# can be triggered. Otherwise gcc doesn't complain.
-FPU_CFLAGS += -mhard-float
-FPU_CFLAGS += $(call cc-option,-msse -mpreferred-stack-boundary=3,-mpreferred-stack-boundary=4)
-endif
-
obj-$(CONFIG_TEST_FPU) += test_fpu.o
test_fpu-y := test_fpu_glue.o test_fpu_impl.o
-CFLAGS_test_fpu_impl.o += $(FPU_CFLAGS)
+CFLAGS_test_fpu_impl.o += $(CC_FLAGS_FPU)
+CFLAGS_REMOVE_test_fpu_impl.o += $(CC_FLAGS_NO_FPU)
# Some KUnit files (hooks.o) need to be built-in even when KUnit is a module,
# so we can't just use obj-$(CONFIG_KUNIT).
--- a/lib/test_fpu_glue.c~selftests-fpu-allow-building-on-other-architectures
+++ a/lib/test_fpu_glue.c
@@ -17,7 +17,7 @@
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/debugfs.h>
-#include <asm/fpu/api.h>
+#include <linux/fpu.h>
#include "test_fpu.h"
@@ -38,6 +38,9 @@ static struct dentry *selftest_dir;
static int __init test_fpu_init(void)
{
+ if (!kernel_fpu_available())
+ return -EINVAL;
+
selftest_dir = debugfs_create_dir("selftest_helpers", NULL);
if (!selftest_dir)
return -ENOMEM;
_
Patches currently in -mm which might be from samuel.holland@xxxxxxxxxx are
arch-add-arch_has_kernel_fpu_support.patch
arm-implement-arch_has_kernel_fpu_support.patch
arm-crypto-use-cc_flags_fpu-for-neon-cflags.patch
arm64-implement-arch_has_kernel_fpu_support.patch
arm64-crypto-use-cc_flags_fpu-for-neon-cflags.patch
lib-raid6-use-cc_flags_fpu-for-neon-cflags.patch
loongarch-implement-arch_has_kernel_fpu_support.patch
powerpc-implement-arch_has_kernel_fpu_support.patch
x86-implement-arch_has_kernel_fpu_support.patch
riscv-add-support-for-kernel-mode-fpu.patch
drm-amd-display-use-arch_has_kernel_fpu_support.patch
selftests-fpu-move-fp-code-to-a-separate-translation-unit.patch
selftests-fpu-allow-building-on-other-architectures.patch
