From 6a181e333954a26f46596b36f82abd14743570fd Mon Sep 17 00:00:00 2001 From: Nick Desaulniers Date: Wed, 25 Sep 2019 11:09:06 -0700 Subject: [PATCH] x86/realmode: Explicitly set entry point via ENTRY in linker script Linking with ld.lld via $ make LD=ld.lld produces the warning: ld.lld: warning: cannot find entry symbol _start; defaulting to 0x1000 Linking with ld.bfd shows the default entry is 0x1000: $ readelf -h arch/x86/realmode/rm/realmode.elf | grep Entry Entry point address: 0x1000 While ld.lld is being pedantic, just set the entry point explicitly, instead of depending on the implicit default. The symbol pa_text_start refers to the start of the .text section, which may not be at 0x1000 if the preceding sections listed in arch/x86/realmode/rm/realmode.lds.S were large enough. This matches behavior in arch/x86/boot/setup.ld. Reported-by: Sedat Dilek Suggested-by: Borislav Petkov Suggested-by: Peter Smith Signed-off-by: Nick Desaulniers Signed-off-by: Borislav Petkov Cc: "H. Peter Anvin" Cc: clang-built-linux@googlegroups.com Cc: grimar@accesssoftek.com Cc: Ingo Molnar Cc: maskray@google.com Cc: ruiu@google.com Cc: Thomas Gleixner Cc: x86-ml Link: https://lkml.kernel.org/r/20190925180908.54260-1-ndesaulniers@google.com Link: https://github.com/ClangBuiltLinux/linux/issues/216 --- arch/x86/realmode/rm/realmode.lds.S | 1 + 1 file changed, 1 insertion(+) diff --git a/arch/x86/realmode/rm/realmode.lds.S b/arch/x86/realmode/rm/realmode.lds.S index 3bb980800c58..64d135d1ee63 100644 --- a/arch/x86/realmode/rm/realmode.lds.S +++ b/arch/x86/realmode/rm/realmode.lds.S @@ -11,6 +11,7 @@ OUTPUT_FORMAT("elf32-i386") OUTPUT_ARCH(i386) +ENTRY(pa_text_start) SECTIONS { -- 2.25.1