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authorNick Desaulniers <ndesaulniers@google.com>2021-10-19 15:36:43 -0700
committerWill Deacon <will@kernel.org>2021-10-21 10:31:38 +0100
commit1907d3ff5a644ad7c07bf3c0a56a0b1864c9e5cf (patch)
tree6e65234f12251bb9e4adf7ebdc12ee4fc1cbdb70
parent5816b3e6577eaa676ceb00a848f0fd65fe2adc29 (diff)
arm64: vdso32: drop the test for dmb ishld
Binutils added support for this instruction in commit e797f7e0b2bedc9328d4a9a0ebc63ca7a2dbbebc which shipped in 2.24 (just missing the 2.23 release) but was cherry-picked into 2.23 in commit 27a50d6755bae906bc73b4ec1a8b448467f0bea1. Thanks to Christian and Simon for helping me with the patch archaeology. According to Documentation/process/changes.rst, the minimum supported version of binutils is 2.23. Since all supported versions of GAS support this instruction, drop the assembler invocation, preprocessor flags/guards, and the cross assembler macro that's now unused. This also avoids a recursive self reference in a follow up cleanup patch. Cc: Christian Biesinger <cbiesinger@google.com> Cc: Simon Marchi <simon.marchi@polymtl.ca> Signed-off-by: Nick Desaulniers <ndesaulniers@google.com> Reviewed-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Reviewed-by: Nathan Chancellor <nathan@kernel.org> Link: https://lore.kernel.org/r/20211019223646.1146945-2-ndesaulniers@google.com Signed-off-by: Will Deacon <will@kernel.org>
-rw-r--r--arch/arm64/include/asm/vdso/compat_barrier.h2
-rw-r--r--arch/arm64/kernel/vdso32/Makefile8
2 files changed, 1 insertions, 9 deletions
diff --git a/arch/arm64/include/asm/vdso/compat_barrier.h b/arch/arm64/include/asm/vdso/compat_barrier.h
index 3fd8fd6d8fc2..fb60a88b5ed4 100644
--- a/arch/arm64/include/asm/vdso/compat_barrier.h
+++ b/arch/arm64/include/asm/vdso/compat_barrier.h
@@ -20,7 +20,7 @@
#define dmb(option) __asm__ __volatile__ ("dmb " #option : : : "memory")
-#if __LINUX_ARM_ARCH__ >= 8 && defined(CONFIG_AS_DMB_ISHLD)
+#if __LINUX_ARM_ARCH__ >= 8
#define aarch32_smp_mb() dmb(ish)
#define aarch32_smp_rmb() dmb(ishld)
#define aarch32_smp_wmb() dmb(ishst)
diff --git a/arch/arm64/kernel/vdso32/Makefile b/arch/arm64/kernel/vdso32/Makefile
index 3dba0c4f8f42..89299a26638b 100644
--- a/arch/arm64/kernel/vdso32/Makefile
+++ b/arch/arm64/kernel/vdso32/Makefile
@@ -29,8 +29,6 @@ cc32-option = $(call try-run,\
$(CC_COMPAT) $(1) -c -x c /dev/null -o "$$TMP",$(1),$(2))
cc32-disable-warning = $(call try-run,\
$(CC_COMPAT) -W$(strip $(1)) -c -x c /dev/null -o "$$TMP",-Wno-$(strip $(1)))
-cc32-as-instr = $(call try-run,\
- printf "%b\n" "$(1)" | $(CC_COMPAT) $(VDSO_AFLAGS) -c -x assembler -o "$$TMP" -,$(2),$(3))
# We cannot use the global flags to compile the vDSO files, the main reason
# being that the 32-bit compiler may be older than the main (64-bit) compiler
@@ -113,12 +111,6 @@ endif
VDSO_AFLAGS := $(VDSO_CAFLAGS)
VDSO_AFLAGS += -D__ASSEMBLY__
-# Check for binutils support for dmb ishld
-dmbinstr := $(call cc32-as-instr,dmb ishld,-DCONFIG_AS_DMB_ISHLD=1)
-
-VDSO_CFLAGS += $(dmbinstr)
-VDSO_AFLAGS += $(dmbinstr)
-
# From arm vDSO Makefile
VDSO_LDFLAGS += -Bsymbolic --no-undefined -soname=linux-vdso.so.1
VDSO_LDFLAGS += -z max-page-size=4096 -z common-page-size=4096