From mboxrd@z Thu Jan 1 00:00:00 1970 From: will.deacon@arm.com (Will Deacon) Date: Mon, 22 Aug 2016 14:48:57 +0100 Subject: [PATCH] arm64: errata: Pass --fix-cortex-a53-843419 to ld if workaround enabled Message-ID: <1471873737-7614-1-git-send-email-will.deacon@arm.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Cortex-A53 erratum 843419 is worked around by the linker, although it is a configure-time option to GCC as to whether ld is actually asked to apply the workaround or not. This patch ensures that we pass --fix-cortex-a53-843419 to the linker when both CONFIG_ARM64_ERRATUM_843419=y and the linker supports the option. Signed-off-by: Will Deacon --- arch/arm64/Kconfig | 15 +++++---------- arch/arm64/Makefile | 9 +++++++++ 2 files changed, 14 insertions(+), 10 deletions(-) diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index bc3f00f586f1..e4b7d10e8e1c 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -415,18 +415,13 @@ config ARM64_ERRATUM_845719 config ARM64_ERRATUM_843419 bool "Cortex-A53: 843419: A load or store might access an incorrect address" - depends on MODULES default y - select ARM64_MODULE_CMODEL_LARGE + select ARM64_MODULE_CMODEL_LARGE if MODULES help - This option builds kernel modules using the large memory model in - order to avoid the use of the ADRP instruction, which can cause - a subsequent memory access to use an incorrect address on Cortex-A53 - parts up to r0p4. - - Note that the kernel itself must be linked with a version of ld - which fixes potentially affected ADRP instructions through the - use of veneers. + This option links the kernel with '--fix-cortex-a53-843419' and + builds modules using the large memory model in order to avoid the use + of the ADRP instruction, which can cause a subsequent memory access + to use an incorrect address on Cortex-A53 parts up to r0p4. If unsure, say Y. diff --git a/arch/arm64/Makefile b/arch/arm64/Makefile index 5b54f8c021d8..c5ad4957e7ee 100644 --- a/arch/arm64/Makefile +++ b/arch/arm64/Makefile @@ -18,6 +18,15 @@ ifneq ($(CONFIG_RELOCATABLE),) LDFLAGS_vmlinux += -pie -Bsymbolic endif +ifeq ($(CONFIG_ARM64_ERRATUM_843419),y) +ld-843419-workaround := $(call ld-option, --fix-cortex-a53-843419) + ifeq ($(ld-843419-workaround),) +$(warning ld does not support --fix-cortex-a53-843419; kernel may be susceptible to erratum) + else +LDFLAGS_vmlinux += --fix-cortex-a53-843419 + endif +endif + KBUILD_DEFCONFIG := defconfig # Check for binutils support for specific extensions -- 2.1.4