On 09/26/2018 08:03 AM, Bin Meng wrote:
Per Microsoft PE Format documentation [1], PointerToSymbolTable and NumberOfSymbols should be zero for an image in the COFF file header. Currently U-Boot is generating *.efi images (eg: helloworld.efi) in which these two members are not zero.
This updates the build rules to tell linker to remove the symbol table completely so that we can generate compliant *.efi images.
[1] https://docs.microsoft.com/zh-cn/windows/desktop/Debug/pe-format
Reported-by: Heinrich Schuchardt xypron.glpk@gmx.de Signed-off-by: Bin Meng bmeng.cn@gmail.com
With the -s switch - PointerToSymbolTable is 0, - NumberOfSymbols is 0.
$ objdump -T lib/efi_loader/helloworld.efi
lib/efi_loader/helloworld.efi: file format pei-i386
objdump: lib/efi_loader/helloworld.efi: not a dynamic object DYNAMIC SYMBOL TABLE: no symbols
So the binaries are now conforming the PE standard.
qemu-x86_defconfig lib/efi_loader/helloworld.efi still contains these sections:
Section[3] .dynamic Section[5] .dynsym
Is this what you expect when you have 0 symbols? Should these sections be removed with strip -R? But anyway these empty tables do no harm.
Reviewed-by: Heinrich Schuchardt xypron.glpk@gmx.de
scripts/Makefile.lib | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib index f8c3fff..91f0b20 100644 --- a/scripts/Makefile.lib +++ b/scripts/Makefile.lib @@ -381,7 +381,7 @@ $(obj)/%.efi: $(obj)/%_efi.so
quiet_cmd_efi_ld = LD $@ cmd_efi_ld = $(LD) -nostdlib -znocombreloc -T $(EFI_LDS_PATH) -shared \
-Bsymbolic $^ -o $@
-Bsymbolic -s $^ -o $@EFI_LDS_PATH = $(srctree)/arch/$(ARCH)/lib/$(EFI_LDS)