Re: [PATCH v3 6/9] xen/arm64: bpi: Add missing code symbol annotations

[Julien Grall <julien@xxxxxxx>]

On 07/05/2024 17:55, Edgar E. Iglesias wrote:
> On Tue, May 7, 2024 at 11:57 AM Julien Grall <julien@xxxxxxx> wrote:
> Hi Julien,
Hi Edgar,

> The reason I choose FUNC for the start of the symbol is because these
> symbols contain
> executable code (not only a table of pointers to code somewhere else)
> and the ELF spec
> says that STT_FUNC means the symbol contains functions or other executable
> code (not only callable functions IIUC):
>
> "STT_FUNC The symbol is associated with a function or other executable code."
> https://refspecs.linuxbase.org/elf/elf.pdf
> (Symbol Table 1-20).
Thanks for the pointer. I originally did intend to suggest the change, 
but then I saw the use of LABEL in x86 (such as svm_stgi_label). There 
are a few others example with LABEL_LOCAL.
AFAICT, this is also executable code which the only difference that it 
is not meant to be called by someone else. Furthermore, LABEL is using 
DO_CODE_ALIGN(...) for the alignment which imply that it is intended to 
be used by executable code. So I thought the only difference was whether 
the label was intended to be used as a function.
> I think using LABEL instead of GLOBAL for the _end labels of these
> code sequences makes sense.
> I'm happy to change the _start labels to LABEL too if you guys feel
> that's better.
I have to admit I am little confused with the difference between LABEL 
vs FUNC. I think I will need some guidance from Jan (he introduced 
linkage.h).
Cheers,

--
Julien Grall