On 06/09/2024 6:58 am, Jan Beulich wrote: > On 05.09.2024 18:10, Andrew Cooper wrote: >> On 05/09/2024 4:42 pm, Jan Beulich wrote: >>> On 05.09.2024 15:06, Andrew Cooper wrote: >>>> --- a/xen/arch/x86/efi/efi-boot.h >>>> +++ b/xen/arch/x86/efi/efi-boot.h >>>> @@ -102,9 +102,6 @@ static void __init efi_arch_relocate_image(unsigned >>>> long delta) >>>> } >>>> } >>>> >>>> -extern const s32 __trampoline_rel_start[], __trampoline_rel_stop[]; >>>> -extern const s32 __trampoline_seg_start[], __trampoline_seg_stop[]; >>> I'd prefer if these stayed here, leaving the 4 symbols as minimally exposed >>> as >>> possible. Recall that efi-boot.h isn't really a header in that sense, but >>> rather a .c file. Elsewhere we keep decls in .c files when they're used in >>> just >>> one CU. >> See Frediano's RFC series, which needs to change this in order to move >> the 32bit relocation logic from asm to C. > And it moves the declarations to the new .c file. Visibility still limited > to that one file. And (afaics) no Misra violation, contrary to what your > later reply to Frediano suggests.
If only there were an easy way to answer the question. https://gitlab.com/xen-project/people/andyhhp/xen/-/jobs/7766305370 Failure: 4 regressions found for clean guidelines service MC3R1.R8.5: (required) An external object or function shall be declared once in one and only one file: violation: 4 >> The only reason efi-boot.h can get away with this right now is because >> the other logic is written entirely in asm. >> >> >> Scope-limiting linker section boundaries more than regular variables is >> weird to me. It's not as if they magically take more care to use than >> regular variables, and trampoline.h is not a wide scope by any means. > It's not "more than", it's "like" (i.e. no matter whether a linker script > or assembly is the origin of the symbol). I'm asking why linker-section-boundary symbols should be treated specially, and not seeing an answer. I assert they do not warrant special treatment, and should live in header files like every other extern symbol we use. ~Andrew
