Build regressions/improvements in v5.16-rc1

[Helge Deller]

On 11/17/21 03:19, Nick Terrell wrote:
>
>
>> On Nov 16, 2021, at 6:05 PM, Randy Dunlap <rdunlap at infradead.org> wrote:
>>
>> On 11/16/21 5:59 PM, Nick Terrell wrote:
>>>> On Nov 15, 2021, at 8:44 AM, Helge Deller <deller at gmx.de> wrote:
>>>>
>>>> On 11/15/21 17:12, Geert Uytterhoeven wrote:
>>>>> On Mon, Nov 15, 2021 at 4:54 PM Geert Uytterhoeven <geert at linux-m68k.org> wrote:
>>>>>> Below is the list of build error/warning regressions/improvements in
>>>>>> v5.16-rc1[1] compared to v5.15[2].
>>>>>>
>>>>>> Summarized:
>>>>>>  - build errors: +20/-13
>>>>>>  - build warnings: +3/-28
>>>>>>
>>>>>> Happy fixing! ;-)
>>>>>>
>>>>>> Thanks to the linux-next team for providing the build service.
>>>>>>
>>>>>> [1] http://kisskb.ellerman.id.au/kisskb/branch/linus/head/fa55b7dcdc43c1aa1ba12bca9d2dd4318c2a0dbf/   (all 90 configs)
>>>>>> [2] http://kisskb.ellerman.id.au/kisskb/branch/linus/head/8bb7eca972ad531c9b149c0a51ab43a417385813/   (all 90 configs)
>>>>>>
>>>>>>
>>>>>> *** ERRORS ***
>>>>>>
>>>>>> 20 error regressions:
>>>>>>  + /kisskb/src/arch/parisc/include/asm/jump_label.h: error: expected ':' before '__stringify':  => 33:4, 18:4
>>>>>>  + /kisskb/src/arch/parisc/include/asm/jump_label.h: error: label 'l_yes' defined but not used [-Werror=unused-label]:  => 38:1, 23:1
>>>>>
>>>>>    due to static_branch_likely() in crypto/api.c
>>>>>
>>>>> parisc-allmodconfig
>>>>
>>>> fixed now in the parisc for-next git tree.
>>>>
>>>>
>>>>>>  + /kisskb/src/drivers/gpu/drm/msm/msm_drv.h: error: "COND" redefined [-Werror]:  => 531
>>>>>>  + /kisskb/src/lib/zstd/compress/zstd_double_fast.c: error: the frame size of 3252 bytes is larger than 1536 bytes [-Werror=frame-larger-than=]:  => 47:1
>>>>>>  + /kisskb/src/lib/zstd/compress/zstd_double_fast.c: error: the frame size of 3360 bytes is larger than 1536 bytes [-Werror=frame-larger-than=]:  => 499:1
>>>>>>  + /kisskb/src/lib/zstd/compress/zstd_double_fast.c: error: the frame size of 5344 bytes is larger than 1536 bytes [-Werror=frame-larger-than=]:  => 334:1
>>>>>>  + /kisskb/src/lib/zstd/compress/zstd_double_fast.c: error: the frame size of 5380 bytes is larger than 1536 bytes [-Werror=frame-larger-than=]:  => 354:1
>>>>>>  + /kisskb/src/lib/zstd/compress/zstd_fast.c: error: the frame size of 1824 bytes is larger than 1536 bytes [-Werror=frame-larger-than=]:  => 372:1
>>>>>>  + /kisskb/src/lib/zstd/compress/zstd_fast.c: error: the frame size of 2224 bytes is larger than 1536 bytes [-Werror=frame-larger-than=]:  => 204:1
>>>>>>  + /kisskb/src/lib/zstd/compress/zstd_fast.c: error: the frame size of 3800 bytes is larger than 1536 bytes [-Werror=frame-larger-than=]:  => 476:1
>>>>>
>>>>> parisc-allmodconfig
>>>>
>>>> parisc needs much bigger frame sizes, so I'm not astonished here.
>>>> During the v5.15 cycl I increased it to 1536 (from 1280), so I'm simply tempted to
>>>> increase it this time to 4096, unless someone has a better idea....
>>> This patch set should fix the zstd stack size warnings [0]. I’ve
>>> verified the fix using the same tooling: gcc-8-hppa-linux-gnu.
>>> I’ll send the PR to Linus tomorrow. I’ve been informed that it
>>> isn't strictly necessary to send the patches to the mailing list
>>> for bug fixes, but its already done, so I’ll wait and see if there
>>> is any feedback.
>>
>> IMO several (or many more) people would disagree with that.
>>
>> "strictly?"  OK, it's probably possible that almost any patch
>> could be merged without being on a mailing list, but it's not
>> desirable (except in the case of "security" patches).
>
> Good to know! Thanks for the advice, I wasn’t really sure what
> the best practice is for sending patches to your own tree, as I
> didn't see anything about it in the maintainer guide.

Nick, thanks a lot for your efforts to get the frame size usage down!

I've applied your patch series to the parisc for-next tree [1], so that it
gets some testing in the upstream for-next tree.
My tests so far are good, although I'm only using gcc-11.

If you don't mind, and if it doesn't generate issues for other
platforms & architectures I could submit them upstream to Linus when
I send the next pull request.

Helge

[1] https://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux.git/log/?h=for-next