On Fri, Jun 21, 2019 at 10:52:37AM +0100, Vincenzo Frascino wrote:
--- /dev/null +++ b/arch/arm64/include/asm/vdso/compat_barrier.h @@ -0,0 +1,51 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/*
- Copyright (C) 2018 ARM Limited
- */
+#ifndef __COMPAT_BARRIER_H +#define __COMPAT_BARRIER_H
+#ifndef __ASSEMBLY__ +/*
- Warning: This code is meant to be used with
- ENABLE_COMPAT_VDSO only.
- */
+#ifndef ENABLE_COMPAT_VDSO +#error This header is meant to be used with ENABLE_COMPAT_VDSO only +#endif
+#ifdef dmb +#undef dmb +#endif
+#if __LINUX_ARM_ARCH__ >= 7 +#define dmb(option) __asm__ __volatile__ ("dmb " #option : : : "memory") +#elif __LINUX_ARM_ARCH__ == 6 +#define dmb(x) __asm__ __volatile__ ("mcr p15, 0, %0, c7, c10, 5" \
: : "r" (0) : "memory")+#else +#define dmb(x) __asm__ __volatile__ ("" : : : "memory") +#endif
We don't need pre-ARMv7 barriers (they've been deprecated and the arm64 kernel actually traps and emulates them by default). Also your Makefile changes never define a __LINUX_ARM_ARCH__ lower than 7. Fix-up below:
------8<-----------------------
From 5655a0313ce7bb731bfed6a19bcfe6b1100b542a Mon Sep 17 00:00:00 2001
From: Catalin Marinas catalin.marinas@arm.com Date: Mon, 24 Jun 2019 12:16:06 +0100 Subject: [PATCH] arm64: compat: No need for pre-ARMv7 barriers on an ARMv8 system
This patch removes the deprecated (pre-ARMv7) compat barriers as they would not be used on an ARMv8 system.
Fixes: a7f71a2c8903 ("arm64: compat: Add vDSO") Signed-off-by: Catalin Marinas catalin.marinas@arm.com --- arch/arm64/include/asm/vdso/compat_barrier.h | 7 ------- 1 file changed, 7 deletions(-)
diff --git a/arch/arm64/include/asm/vdso/compat_barrier.h b/arch/arm64/include/asm/vdso/compat_barrier.h index ea24ea856b07..fb60a88b5ed4 100644 --- a/arch/arm64/include/asm/vdso/compat_barrier.h +++ b/arch/arm64/include/asm/vdso/compat_barrier.h @@ -18,14 +18,7 @@ #undef dmb #endif
-#if __LINUX_ARM_ARCH__ >= 7 #define dmb(option) __asm__ __volatile__ ("dmb " #option : : : "memory") -#elif __LINUX_ARM_ARCH__ == 6 -#define dmb(x) __asm__ __volatile__ ("mcr p15, 0, %0, c7, c10, 5" \ - : : "r" (0) : "memory") -#else -#define dmb(x) __asm__ __volatile__ ("" : : : "memory") -#endif
#if __LINUX_ARM_ARCH__ >= 8 #define aarch32_smp_mb() dmb(ish)