diff options
| author | Ard Biesheuvel <ardb@kernel.org> | 2020-07-21 09:21:08 +0100 |
|---|---|---|
| committer | Russell King <rmk+kernel@armlinux.org.uk> | 2020-07-28 10:52:11 +0100 |
| commit | 67b0141bd12d3a609d47ebbb53a4df67e3fdf4c4 (patch) | |
| tree | 0a99230176eccbbc525a7efcb71028eaa74f073a | |
| parent | 4d44a399b5c3814292be8eb3c936be5d95a9a5d6 (diff) | |
| download | linux-67b0141bd12d3a609d47ebbb53a4df67e3fdf4c4.tar.bz2 | |
ARM: 8995/1: drop Thumb-2 workaround for ancient binutils
The CONFIG_THUMB2_AVOID_R_ARM_THM_JUMP11 workaround addresses an issue
which was fixed before the oldest supported binutils (2.23 at this time)
were released. So we can remove it now.
Acked-by: Dave Martin <Dave.Martin@arm.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
| -rw-r--r-- | arch/arm/Kconfig | 31 | ||||
| -rw-r--r-- | arch/arm/Makefile | 4 |
2 files changed, 0 insertions, 35 deletions
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig index 910e89f9023c..1b65ff94ad1c 100644 --- a/arch/arm/Kconfig +++ b/arch/arm/Kconfig @@ -1422,37 +1422,6 @@ config THUMB2_KERNEL If unsure, say N. -config THUMB2_AVOID_R_ARM_THM_JUMP11 - bool "Work around buggy Thumb-2 short branch relocations in gas" - depends on THUMB2_KERNEL && MODULES - default y - help - Various binutils versions can resolve Thumb-2 branches to - locally-defined, preemptible global symbols as short-range "b.n" - branch instructions. - - This is a problem, because there's no guarantee the final - destination of the symbol, or any candidate locations for a - trampoline, are within range of the branch. For this reason, the - kernel does not support fixing up the R_ARM_THM_JUMP11 (102) - relocation in modules at all, and it makes little sense to add - support. - - The symptom is that the kernel fails with an "unsupported - relocation" error when loading some modules. - - Until fixed tools are available, passing - -fno-optimize-sibling-calls to gcc should prevent gcc generating - code which hits this problem, at the cost of a bit of extra runtime - stack usage in some cases. - - The problem is described in more detail at: - https://bugs.launchpad.net/binutils-linaro/+bug/725126 - - Only Thumb-2 kernels are affected. - - Unless you are sure your tools don't have this problem, say Y. - config ARM_PATCH_IDIV bool "Runtime patch udiv/sdiv instructions into __aeabi_{u}idiv()" depends on CPU_32v7 && !XIP_KERNEL diff --git a/arch/arm/Makefile b/arch/arm/Makefile index 2731c20dee58..f0ef23865df7 100644 --- a/arch/arm/Makefile +++ b/arch/arm/Makefile @@ -123,10 +123,6 @@ AFLAGS_NOWARN :=$(call as-option,-Wa$(comma)-mno-warn-deprecated,-Wa$(comma)-W) ifeq ($(CONFIG_THUMB2_KERNEL),y) CFLAGS_ISA :=-mthumb -Wa,-mimplicit-it=always $(AFLAGS_NOWARN) AFLAGS_ISA :=$(CFLAGS_ISA) -Wa$(comma)-mthumb -# Work around buggy relocation from gas if requested: -ifeq ($(CONFIG_THUMB2_AVOID_R_ARM_THM_JUMP11),y) -KBUILD_CFLAGS_MODULE +=-fno-optimize-sibling-calls -endif else CFLAGS_ISA :=$(call cc-option,-marm,) $(AFLAGS_NOWARN) AFLAGS_ISA :=$(CFLAGS_ISA) |