powerpc: Allow CONFIG_PPC64_BIG_ENDIAN_ELF_ABI_V2 with ld.lld 15+

Commit 5017b4594672 ("powerpc/64: Option to build big-endian with ELFv2
ABI") restricted the ELFv2 ABI configuration such that it can only be
selected when linking with ld.bfd, due to lack of testing with LLVM.

ld.lld can link ELFv2 kernels without any issues; in fact, it is the
only ABI that ld.lld supports, as ELFv1 is not supported in ld.lld.

As this has not seen a ton of real world testing yet, be conservative
and only allow this option to be selected with the latest stable release
of LLVM (15.x) and newer.

While in the area, remove 'default n', as it is unnecessary to specify
it explicitly since all boolean/tristate configuration symbols default
to n.

Tested-by: "Erhard F." <erhard_f@mailbox.org>
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230118-ppc64-elfv2-llvm-v1-3-b9e2ec9da11d@kernel.org

diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index a6c4407d3ec835a972b78f15fb3033f7492b2d60..47017975fc2b2d8af8fab7e255744a32046d27c8 100644 (file)
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -616,8 +616,7 @@ config PPC64_BIG_ENDIAN_ELF_ABI_V2
        bool "Build big-endian kernel using ELF ABI V2 (EXPERIMENTAL)"
        depends on PPC64 && CPU_BIG_ENDIAN
        depends on CC_HAS_ELFV2
-       depends on LD_IS_BFD && LD_VERSION >= 22400
-       default n
+       depends on LD_VERSION >= 22400 || LLD_VERSION >= 150000
        help
          This builds the kernel image using the "Power Architecture 64-Bit ELF
          V2 ABI Specification", which has a reduced stack overhead and faster