ARM: 9070/1: Make UNWINDER_ARM depend on ld.bfd or ld.lld 11.0.0+

When linking aspeed_g5_defconfig with ld.lld 10.0.1, the following error
occurs:

ld.lld: error: .tmp_vmlinux.kallsyms1:(.ARM.exidx+0x34D98): relocation
R_ARM_PREL31 out of range: 2135538592 is not in [-1073741824,
1073741823]

This was resolved in ld.lld 11.0.0 but the minimum supported version of
ld.lld for the kernel is 10.0.1. Prevent CONFIG_UNWINDER_ARM from being
selected in this case so that the problematic sections cannot be
created.

Link: https://github.com/ClangBuiltLinux/linux/issues/732
Link: https://github.com/llvm/llvm-project/commit/48aebfc908ba7b9372aaa478a9c200789491096e
Suggested-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>

diff --git a/arch/arm/Kconfig.debug b/arch/arm/Kconfig.debug
index 3601649..7902bc2 100644 (file)
--- a/arch/arm/Kconfig.debug
+++ b/arch/arm/Kconfig.debug
@@ -66,6 +66,8 @@ config UNWINDER_FRAME_POINTER
 config UNWINDER_ARM
        bool "ARM EABI stack unwinder"
        depends on AEABI && !FUNCTION_GRAPH_TRACER
+       # https://github.com/ClangBuiltLinux/linux/issues/732
+       depends on !LD_IS_LLD || LLD_VERSION >= 110000
        select ARM_UNWIND
        help
          This option enables stack unwinding support in the kernel