From 712676ea2bb3882a852bcf49862c4247317fc9b2 Mon Sep 17 00:00:00 2001 From: Adhemerval Zanella Date: Tue, 3 Sep 2024 12:09:17 +0000 Subject: 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 Reviewed-by: Ard Biesheuvel Acked-by: Will Deacon Signed-off-by: Jason A. Donenfeld --- tools/include/linux/compiler.h | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'tools/include') diff --git a/tools/include/linux/compiler.h b/tools/include/linux/compiler.h index 6f7f22ac9da5..4366da278033 100644 --- a/tools/include/linux/compiler.h +++ b/tools/include/linux/compiler.h @@ -2,6 +2,8 @@ #ifndef _TOOLS_LINUX_COMPILER_H_ #define _TOOLS_LINUX_COMPILER_H_ +#ifndef __ASSEMBLY__ + #include #ifndef __compiletime_error @@ -224,4 +226,6 @@ static __always_inline void __write_once_size(volatile void *p, void *res, int s __asm__ ("" : "=r" (var) : "0" (var)) #endif +#endif /* __ASSEMBLY__ */ + #endif /* _TOOLS_LINUX_COMPILER_H */ -- cgit v1.2.3