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| author | Adhemerval Zanella <adhemerval.zanella@linaro.org> | 2024-09-03 12:09:17 +0000 |
|---|---|---|
| committer | Jason A. Donenfeld <Jason@zx2c4.com> | 2024-09-13 17:28:36 +0200 |
| commit | 712676ea2bb3882a852bcf49862c4247317fc9b2 (patch) | |
| tree | 17d406ce2b8c3ee29444e36f3ff9ba9abaabc22d /arch/arm64/kernel/vdso/Makefile | |
| parent | 2c2ca3416b4090aef8c646adccfc3be4b712db8a (diff) | |
arm64: vDSO: Wire up getrandom() vDSO implementation
Hook up the generic vDSO implementation to the aarch64 vDSO data page.
The _vdso_rng_data required data is placed within the _vdso_data vvar
page, by using a offset larger than the vdso_data.
The vDSO function requires a ChaCha20 implementation that does not write
to the stack, and that can do an entire ChaCha20 permutation. The one
provided uses NEON on the permute operation, with a fallback to the
syscall for chips that do not support AdvSIMD.
This also passes the vdso_test_chacha test along with
vdso_test_getrandom. The vdso_test_getrandom bench-single result on
Neoverse-N1 shows:
vdso: 25000000 times in 0.783884250 seconds
libc: 25000000 times in 8.780275399 seconds
syscall: 25000000 times in 8.786581518 seconds
A small fixup to arch/arm64/include/asm/mman.h was required to avoid
pulling kernel code into the vDSO, similar to what's already done in
arch/arm64/include/asm/rwonce.h.
Signed-off-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
Acked-by: Will Deacon <will@kernel.org>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Diffstat (limited to 'arch/arm64/kernel/vdso/Makefile')
| -rw-r--r-- | arch/arm64/kernel/vdso/Makefile | 25 |
1 files changed, 17 insertions, 8 deletions
diff --git a/arch/arm64/kernel/vdso/Makefile b/arch/arm64/kernel/vdso/Makefile index d11da6461278..35685c036044 100644 --- a/arch/arm64/kernel/vdso/Makefile +++ b/arch/arm64/kernel/vdso/Makefile @@ -9,7 +9,7 @@ # Include the generic Makefile to check the built vdso. include $(srctree)/lib/vdso/Makefile -obj-vdso := vgettimeofday.o note.o sigreturn.o +obj-vdso := vgettimeofday.o note.o sigreturn.o vgetrandom.o vgetrandom-chacha.o # Build rules targets := $(obj-vdso) vdso.so vdso.so.dbg @@ -34,19 +34,28 @@ ccflags-y := -fno-common -fno-builtin -fno-stack-protector -ffixed-x18 ccflags-y += -DDISABLE_BRANCH_PROFILING -DBUILD_VDSO # -Wmissing-prototypes and -Wmissing-declarations are removed from -# the CFLAGS of vgettimeofday.c to make possible to build the -# kernel with CONFIG_WERROR enabled. -CFLAGS_REMOVE_vgettimeofday.o = $(CC_FLAGS_FTRACE) -Os $(CC_FLAGS_SCS) \ - $(RANDSTRUCT_CFLAGS) $(GCC_PLUGINS_CFLAGS) \ - $(CC_FLAGS_LTO) $(CC_FLAGS_CFI) \ - -Wmissing-prototypes -Wmissing-declarations +# the CFLAGS to make possible to build the kernel with CONFIG_WERROR enabled. +CC_FLAGS_REMOVE_VDSO := $(CC_FLAGS_FTRACE) -Os $(CC_FLAGS_SCS) \ + $(RANDSTRUCT_CFLAGS) $(GCC_PLUGINS_CFLAGS) \ + $(CC_FLAGS_LTO) $(CC_FLAGS_CFI) \ + -Wmissing-prototypes -Wmissing-declarations -CFLAGS_vgettimeofday.o = -O2 -mcmodel=tiny -fasynchronous-unwind-tables +CC_FLAGS_ADD_VDSO := -O2 -mcmodel=tiny -fasynchronous-unwind-tables + +CFLAGS_REMOVE_vgettimeofday.o = $(CC_FLAGS_REMOVE_VDSO) +CFLAGS_REMOVE_vgetrandom.o = $(CC_FLAGS_REMOVE_VDSO) + +CFLAGS_vgettimeofday.o = $(CC_FLAGS_ADD_VDSO) +CFLAGS_vgetrandom.o = $(CC_FLAGS_ADD_VDSO) ifneq ($(c-gettimeofday-y),) CFLAGS_vgettimeofday.o += -include $(c-gettimeofday-y) endif +ifneq ($(c-getrandom-y),) + CFLAGS_vgetrandom.o += -include $(c-getrandom-y) +endif + targets += vdso.lds CPPFLAGS_vdso.lds += -P -C -U$(ARCH) |