AARCH64 clean bss bug

[Ilias Apalodimas]

Hi Brock

On Sun Jun 29, 2025 at 7:37 AM EEST, brock_zheng wrote:
>
> Hi, all
>
>     I found a bug on AARCH64 platform about clean .bss section after relocating.
>
>     In crt0_64.S, it use instruction 'ldr' to load the start/stop
>     address of BSS after relocating.  My testing shows that
>     __bss_start loaded successfuly, but 'x1 <= __bss_end' got the
>     address _BEFORE_ allocating.o

One of the problems when using the literal pool is that the access is PC-relative, but
the entry itself contains an asbolute address. This code runs after relocation right?
It the literal pool entries relocated?
Any idea why __bss_end is wrong? It would be helpful to have a more complete commit message

>
>     If I swap the two instruction sequence, the result is swapped
>     also. But neither code can gives the right result of those two
>     addesses _AFTER_ relocation.
>
>     my patch use 'adr' instead of 'ldr', seems OK for my RK3568 chip.

Uisng adr for linker symbols is fine, but can you please use adrp+add instead of adr?

Thanks
/Ilias
>
>
> --
> Brock Zheng <yzheng at techyauld.com>
> 郑 祎
>
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