clang/ld.lld build fails with `can't create dynamic relocation R_PPC64_ADDR64 against local symbol in readonly segment`

[Paul Menzel]

Dear Linux folks,


I just wanted to make you aware that building Linux for ppc64le with 
clang/lld.ld fails with [1]:

     ld.lld: error: can't create dynamic relocation R_PPC64_ADDR64 
against symbol: empty_zero_page in readonly segment; recompile object 
files with -fPIC or pass '-Wl,-z,notext' to allow text relocations in 
the output
     >>> defined in arch/powerpc/kernel/head_64.o
     >>> referenced by 
arch/powerpc/kernel/head_64.o:(___ksymtab+empty_zero_page+0x0)

The patch below from one of the comments [2] fixes it.

--- i/arch/powerpc/Makefile
+++ w/arch/powerpc/Makefile
@@ -122,7 +122,7 @@ cflags-$(CONFIG_STACKPROTECTOR)     += 
-mstack-protector-guard-reg=r2
  endif

  LDFLAGS_vmlinux-y := -Bstatic
-LDFLAGS_vmlinux-$(CONFIG_RELOCATABLE) := -pie
+LDFLAGS_vmlinux-$(CONFIG_RELOCATABLE) := -pie -z notext
  LDFLAGS_vmlinux        := $(LDFLAGS_vmlinux-y)
  LDFLAGS_vmlinux += $(call ld-option,--orphan-handling=warn)


Kind regards,

Paul


[1]: https://github.com/ClangBuiltLinux/linux/issues/811
[2]: 
https://github.com/ClangBuiltLinux/linux/issues/811#issuecomment-568316320