[Buildroot] [PATCH] board/qemu/sh4-r2d: fix sh4 kernel bug with Binutils 2.33

[Romain Naour]

Hello Thomas, All,

Le 15/03/2020 à 21:46, Romain Naour a écrit :
> Hello Thomas,
> 
> Le 30/12/2019 à 15:16, Romain Naour a écrit :
>> Hello Thomas,
>>
>> Le 30/12/2019 à 14:53, Thomas Petazzoni a écrit :
>>> Hello Romain,
>>>
>>> On Mon, 30 Dec 2019 14:36:40 +0100
>>> Romain Naour <romain.naour at gmail.com> wrote:
>>>
>>>> Remove the Binutils patch reverting [1] that trigger a sh4 kernel bug
>>>> with Binutils >= 2.33.
>>>> Add two kernel patch provided by Alan Modra [2] that fix alignment of rodata.
>>>>
>>>> [1] https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=ebd2263ba9a9124d93bbc0ece63d7e0fae89b40e
>>>> [2] https://www.sourceware.org/ml/binutils/2019-12/msg00112.html
>>>>
>>>> Signed-off-by: Romain Naour <romain.naour at gmail.com>
>>>
>>> Thanks a lot for those fixes. Have the kernel patches been submitted
>>> upstream, and accepted?
>>
>> Not yet, I replied to Alan Modra to do so [1].
> 
> I just posted theses two patches to the linux-sh mailing list:
> 
> https://patchwork.kernel.org/project/linux-sh/list/?series=256703
> 
> We need to move forward to add binutils 2.34.

Those patches are going to be merged for kernel 5.8 after being acked by kernel
maintainers:

https://patchwork.kernel.org/project/linux-sh/list/?series=256703

Best regards,
Romain


> 
> Best regards,
> Romain
> 
>>
>>>
>>> One issue with your change is of course that now the fix only works
>>> when building the specific qemu_sh4 defconfigs. When not using one of
>>> those defconfigs, but simply building the regular Linux kernel for SH4,
>>> will lead to a kernel that no longer boots.
>>
>> Indeed but I don't think is great to keep the non-upstream patch I've made
>> reverting [2] for Binutils >= 2.33 for all architectures just to workaround a
>> sh4 kernel bug. At the time I didn't know that was a sh4 kernel bug...
>>
>> The two sh4 kernel patches are probably easy to backport as soon as a sh4
>> toolchain using Binutils >= 2.33 is used.
>>
>> [1] https://www.sourceware.org/ml/binutils/2019-12/msg00386.html
>> [2]
>> https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;a=commitdiff;h=ebd2263ba9a9124d93bbc0ece63d7e0fae89b40e
>>
>> Best regards,
>> Romain
>>
>>>
>>> Thomas
>>>
>>
>