Re: RTL9300 (mips) fails to boot with commit d4a7f2510ff4 ("vmlinux.lds.h: Adjust symbol ordering in text output section")

[Chris Packham <chris.packham@alliedtelesis.co.nz>]

On 26/11/24 07:48, Rong Xu wrote:
> Thanks for confirming this! It looks like we do need to put all
> symbols from head.o before any other symbols.
> To be clear, the patch I mentioned was not trying to do that -- it
> just makes sure the _stext is in the right places.
Looking at other architectures it may just be a matter of adding __HEAD 
to an appropriate place in arch/mips/kernel/head.S and HEAD_TEXT_SECTION 
to arch/mips/kernel/vmlinux.lds.S. It might even be possible to drop 
mips from scripts/head-object-list.txt.

> I'll draft a patch for this.

I can give any patch a quick test on my setup.

>
> On Sun, Nov 24, 2024 at 12:40 PM Chris Packham
> <Chris.Packham@alliedtelesis.co.nz> wrote:
>> Hi Rong,
>>
>> On 22/11/24 18:02, Rong Xu wrote:
>>> Does the following patch fix your issue?
>>> https://lore.kernel.org/lkml/CAK7LNAQSpM2hh2=Wgribb92nHF5_peRb+gxdO1Bt1MkeL8N+hw@mail.gmail.com/t/
>>>
>>> Masahiro Yamada already applied the patch to kbuild-tree.
>>>
>>> I also proposed a similar fix as yours. But we believe the above patch
>>> should also work (and probably is better).
>>>
>>> Please try and let us know.
>> Looks like linux-next already has that patch and no it doesn't fix my
>> issue. For the record here's the start of my System.map
>>
>> $ head System.map
>> ffffffff80100000 T __split_text_end
>> ffffffff80100000 T __split_text_start
>> ffffffff80100000 T __unlikely_text_start
>> ffffffff80100000 T _stext
>> ffffffff80100000 T _text
>> ffffffff80100000 t run_init_process
>> ffffffff80100138 t try_to_run_init_process
>> ffffffff8010018c t put_page
>> ffffffff801001d0 t nr_blocks.isra.0
>> ffffffff80100208 T ack_bad_irq
>>
>> It does look like whatever is supposed to put head.o first isn't kicking
>> in for me.
>>
>>> Thanks!
>>>
>>> -Rong
>>>
>>> On Thu, Nov 21, 2024 at 6:29 PM Chris Packham
>>> <chris.packham@alliedtelesis.co.nz> wrote:
>>>> On 22/11/24 14:58, Chris Packham wrote:
>>>>> Hi Rong,
>>>>>
>>>>> I was just trying some of my in-flight changes against linux-next and
>>>>> found that my RTL9300* based board no longer boots (nothing on the
>>>>> serial console after U-Boot hands off to the kernel).
>>>>>
>>>>> A bisect between Linus's tree and linux-next/master points to commit
>>>>> d4a7f2510ff4 ("vmlinux.lds.h: Adjust symbol ordering in text output
>>>>> section"). A build on d4a7f2510ff4^ boots successfully. That series is
>>>>> well beyond my area of knowledge, there may be something that the MIPS
>>>>> SoCs are doing (or not doing) that is being affected by the sections
>>>>> moving.
>>>> Based on the sparc change that accompanied this commit the following
>>>> does seem to restore working order for me:
>>>>
>>>> diff --git a/arch/mips/kernel/vmlinux.lds.S b/arch/mips/kernel/vmlinux.lds.S
>>>> index d575f945d422..e90b0f68290c 100644
>>>> --- a/arch/mips/kernel/vmlinux.lds.S
>>>> +++ b/arch/mips/kernel/vmlinux.lds.S
>>>> @@ -62,6 +62,8 @@ SECTIONS
>>>>            _text = .;      /* Text and read-only data */
>>>>            _stext = .;
>>>>            .text : {
>>>> +               /* Match text section symbols in head.S first */
>>>> +               *head.o(.text)
>>>>                    TEXT_TEXT
>>>>                    SCHED_TEXT
>>>>                    LOCK_TEXT
>>>>
>>>> No idea if that's appropriate
>>>>