[PATCH v11 03/29] linker_lists: set LINKER_LIST_ALIGN to 8 for CPU_MIPS64

[Jerome Forissier]

On 10/4/24 14:04, Heinrich Schuchardt wrote:
> On 03.10.24 17:22, Jerome Forissier wrote:
>> Note: Patch posted separately [0].
>>
>> [0] https://patchwork.ozlabs.org/project/uboot/patch/20241003142030.1610222-1-jerome.forissier@linaro.org/
>>
>> CPU_MIPS64 needs 8-byte alignment on the linker lists, otherwise an
>> exception may occur. Fixes an issue found on malta64 with QEMU:
>>
>>   Breakpoint 1, lists_driver_lookup_name (name=0xffffffffbe043578 "root_driver") at /home/uboot/u-boot/drivers/core/lists.c:31
>>   31                      if (!strcmp(name, entry->name))
>>   [...]
>>   ld      a1,0(s0)
>>
>>   (gdb) p/x &entry->name
>>   0xffffffffbe04b0d4
>>   (gdb) p/x $s0
>>   0xffffffffbe04b0d4
>>
>>   $ grep __u_boot_list /tmp/malta64/u-boot.objdump
>>   4 __u_boot_list 000018e0  ffffffffbe04a4d4  ffffffffbe04a4d4  0004a584  2**2
>>
>> Signed-off-by: Jerome Forissier <jerome.forissier at linaro.org>
>> ---
>>   arch/Kconfig | 2 +-
>>   1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/arch/Kconfig b/arch/Kconfig
>> index 8f1f4667012..8f4df849801 100644
>> --- a/arch/Kconfig
>> +++ b/arch/Kconfig
>> @@ -45,7 +45,7 @@ config SYS_CACHELINE_SIZE
>>   config LINKER_LIST_ALIGN
>>       int
>>       default 32 if SANDBOX
>> -    default 8 if ARM64 || X86
>> +    default 8 if ARM64 || X86 || CPU_MIPS64
> 
> Shouldn't we set 8 byte alignment on all 64bit architectures including
> riscv64?
> 
>     default 8 if 64BIT

Makes sense.

> 
> @Simon
> I would not know why 32bit X86 should need 8 byte alignment.
> I am a bit astonished that you chose 32 byte alignment for the Sandbox.
> Is there any justification to use more than 4 on the 32bit Sandbox and
> more than 8 on the 64bit Sandbox? If yes, we should document it via a
> comment.

I tried running what CI does manually (.azure_pipelines.yml) with
"default 32 if SANDBOX" removed, and I got SIGSEGV with
TEST_PY_BD=sandbox. OTOH, TEST_PY_BD=sandbox64 worked fine but it might
have been a fluke.

Thanks,
-- 
Jerome

> 
> Best regards
> 
> Heinrich
> 
>>       default 4
>>       help
>>         Force the each linker list to be aligned to this boundary. This
>