randconfig fixes for 5.10.y

randconfig fixes for 5.10.y

[Dan Carpenter]

I did some randconfig testing on 5.10.y and the following patches are
required.

d7a7d721064c5 ("media: ti-vpe: cal: avoid FIELD_GET assertion")
42d95d1b3a9c6 ("drm/rcar: stop using 'imply' for dependencies")

The first patch is only required on 5.10.y.
The second "drm/rcar" commit is required in 5.15.y as well.

I'm going to be doing regular randconfig testing on stable so let me
know if you have any advice.

regards,
dan carpenter

Re: randconfig fixes for 5.10.y

[Arnd Bergmann]

On Tue, May 30, 2023, at 10:22, Dan Carpenter wrote:
>
> I'm going to be doing regular randconfig testing on stable so let me
> know if you have any advice.

Just one thing: In my spot for random projects, I occasionally
publish my latest "randconfig-*" branch, which may help you figure
out if I have seen a particular build failure before:

https://git.kernel.org/pub/scm/linux/kernel/git/arnd/playground.git/refs/heads

This tree should build without any warnings or errors on arm, arm64
and x86, so if you run into something that you can't immediately
see if it as a fix already, you can try bisecting against the
latest branch there to see how I addressed it locally or upstream.

It's a mix of patches that I submitted already but were not picked
up yet, that might need a minor rework based on comments, or that
are not acceptable for one reason or another.

      Arnd

Re: randconfig fixes for 5.10.y

[Dan Carpenter]

On Tue, May 30, 2023 at 10:53:55AM +0200, Arnd Bergmann wrote:
> On Tue, May 30, 2023, at 10:22, Dan Carpenter wrote:
> >
> > I'm going to be doing regular randconfig testing on stable so let me
> > know if you have any advice.
> 
> Just one thing: In my spot for random projects, I occasionally
> publish my latest "randconfig-*" branch, which may help you figure
> out if I have seen a particular build failure before:
> 
> https://git.kernel.org/pub/scm/linux/kernel/git/arnd/playground.git/refs/heads
> 
> This tree should build without any warnings or errors on arm, arm64
> and x86, so if you run into something that you can't immediately
> see if it as a fix already, you can try bisecting against the
> latest branch there to see how I addressed it locally or upstream.
> 
> It's a mix of patches that I submitted already but were not picked
> up yet, that might need a minor rework based on comments, or that
> are not acceptable for one reason or another.

Ah, yeah.  Thanks.  Scripting to automatically bisect would be useful.
Btw, I reported one that isn't fixed on randconfig-6.4.

https://lore.kernel.org/all/1770d098-8dc7-4906-bed2-1addf8a6794d@kili.mountain/

  CC [M]  crypto/twofish_common.o
crypto/twofish_common.c: In function ‘__twofish_setkey’:
crypto/twofish_common.c:683:1: warning: the frame size of 2064 bytes is larger than 2048 bytes [-Wframe-larger-than=]
  683 | }
      | ^
  CHECK   crypto/twofish_common.c

regards,
dan carpenter

Re: randconfig fixes for 5.10.y

[Arnd Bergmann]

On Tue, May 30, 2023, at 17:38, Dan Carpenter wrote:
> On Tue, May 30, 2023 at 10:53:55AM +0200, Arnd Bergmann wrote:
>> On Tue, May 30, 2023, at 10:22, Dan Carpenter wrote:
>
> Ah, yeah.  Thanks.  Scripting to automatically bisect would be useful.
> Btw, I reported one that isn't fixed on randconfig-6.4.
>
> https://lore.kernel.org/all/1770d098-8dc7-4906-bed2-1addf8a6794d@kili.mountain/
>
>   CC [M]  crypto/twofish_common.o
> crypto/twofish_common.c: In function ‘__twofish_setkey’:
> crypto/twofish_common.c:683:1: warning: the frame size of 2064 bytes is 
> larger than 2048 bytes [-Wframe-larger-than=]
>   683 | }
>       | ^
>   CHECK   crypto/twofish_common.c

Thanks for the report, I forgot about this bit.

I have a small fragment that I pass to the randconfig generator
to avoid some common problems and also give me much faster
builds:

# maximize search space, disable options not worth testing
CONFIG_COMPILE_TEST=y
# reduce compile-time dependencies
CONFIG_STANDALONE=y
CONFIG_PREVENT_FIRMWARE_BUILD=y

CONFIG_COMPILE_TEST=y forces a number of options to be
hidden from build tests, which is generally super useful.
The one that ended up hiding the stack growth above is
CONFIG_GCOV_PROFILE_ALL. I'll try enabling it for a few
builds to see what else shows up with it.

        Arnd

Re: randconfig fixes for 5.10.y

[Arnd Bergmann]

On Tue, May 30, 2023, at 21:02, Arnd Bergmann wrote:
>
> CONFIG_COMPILE_TEST=y forces a number of options to be
> hidden from build tests, which is generally super useful.
> The one that ended up hiding the stack growth above is
> CONFIG_GCOV_PROFILE_ALL. I'll try enabling it for a few
> builds to see what else shows up with it.

Update: you already pointed to UBSAN_SANITIZE_ALL causing
this, I can confirm that this is also the case. With your
config, the combination of CONFIG_GCOV_PROFILE_ALL and
CONFIG_UBSAN_SANITIZE_ALL causes the compiler to completely
mess up register allocation in this code, disabling either
of the two gets it below the boundary.

     Arnd

Re: randconfig fixes for 5.10.y

[Arnd Bergmann]

On Tue, May 30, 2023, at 21:20, Arnd Bergmann wrote:
> On Tue, May 30, 2023, at 21:02, Arnd Bergmann wrote:
>>
>> CONFIG_COMPILE_TEST=y forces a number of options to be
>> hidden from build tests, which is generally super useful.
>> The one that ended up hiding the stack growth above is
>> CONFIG_GCOV_PROFILE_ALL. I'll try enabling it for a few
>> builds to see what else shows up with it.
>
> Update: you already pointed to UBSAN_SANITIZE_ALL causing
> this, I can confirm that this is also the case. With your
> config, the combination of CONFIG_GCOV_PROFILE_ALL and
> CONFIG_UBSAN_SANITIZE_ALL causes the compiler to completely
> mess up register allocation in this code, disabling either
> of the two gets it below the boundary.

After a night of randconfig builds with both UBSAN_SANITIZE_ALL
and GCOV_PROFILE_ALL force-enabled, these are the ones I found,
listing only the worst size for each function (using gcc-13.1).
None of these show up without GCOV though:

crypto/twofish_common.c:683:1: error: the frame size of 2040 bytes is larger than 1024 bytes [-Werror=frame-larger-than=]
crypto/twofish_common.c:683:1: error: the frame size of 2336 bytes is larger than 2048 bytes [-Werror=frame-larger-than=]
drivers/media/platform/mediatek/vcodec/vdec/vdec_vp9_req_lat_if.c:1589:1: error: the frame size of 1696 bytes is larger than 1400 bytes [-Werror=frame-larger-than=]
drivers/media/platform/verisilicon/hantro_g2_vp9_dec.c:754:1: error: the frame size of 1260 bytes is larger than 1024 bytes [-Werror=frame-larger-than=]
drivers/staging/media/ipu3/ipu3-css-params.c:1206:1: error: the frame size of 1080 bytes is larger than 1024 bytes [-Werror=frame-larger-than=]
drivers/staging/media/rkvdec/rkvdec-vp9.c:1042:1: error: the frame size of 1660 bytes is larger than 1024 bytes [-Werror=frame-larger-than=]
drivers/staging/media/rkvdec/rkvdec-vp9.c:1042:1: error: the frame size of 2176 bytes is larger than 2048 bytes [-Werror=frame-larger-than=]
drivers/staging/media/rkvdec/rkvdec-vp9.c:995:1: error: the frame size of 1656 bytes is larger than 1024 bytes [-Werror=frame-larger-than=]

      Arnd

Re: randconfig fixes for 5.10.y

[Nick Desaulniers]

On Wed, May 31, 2023 at 3:12 AM Arnd Bergmann <arnd@arndb.de> wrote:
>
> On Tue, May 30, 2023, at 21:20, Arnd Bergmann wrote:
> > On Tue, May 30, 2023, at 21:02, Arnd Bergmann wrote:
> >>
> >> CONFIG_COMPILE_TEST=y forces a number of options to be
> >> hidden from build tests, which is generally super useful.
> >> The one that ended up hiding the stack growth above is
> >> CONFIG_GCOV_PROFILE_ALL. I'll try enabling it for a few
> >> builds to see what else shows up with it.
> >
> > Update: you already pointed to UBSAN_SANITIZE_ALL causing
> > this, I can confirm that this is also the case. With your
> > config, the combination of CONFIG_GCOV_PROFILE_ALL and
> > CONFIG_UBSAN_SANITIZE_ALL causes the compiler to completely
> > mess up register allocation in this code, disabling either
> > of the two gets it below the boundary.
>
> After a night of randconfig builds with both UBSAN_SANITIZE_ALL
> and GCOV_PROFILE_ALL force-enabled, these are the ones I found,
> listing only the worst size for each function (using gcc-13.1).

In LLVM, a recent change we made was when the sanitizers are enabled,
the GCOV instrumentation is not checked by the sanitizers as that
results in excessive code growth.
https://reviews.llvm.org/D150460

> None of these show up without GCOV though:
>
> crypto/twofish_common.c:683:1: error: the frame size of 2040 bytes is larger than 1024 bytes [-Werror=frame-larger-than=]
> crypto/twofish_common.c:683:1: error: the frame size of 2336 bytes is larger than 2048 bytes [-Werror=frame-larger-than=]
> drivers/media/platform/mediatek/vcodec/vdec/vdec_vp9_req_lat_if.c:1589:1: error: the frame size of 1696 bytes is larger than 1400 bytes [-Werror=frame-larger-than=]
> drivers/media/platform/verisilicon/hantro_g2_vp9_dec.c:754:1: error: the frame size of 1260 bytes is larger than 1024 bytes [-Werror=frame-larger-than=]
> drivers/staging/media/ipu3/ipu3-css-params.c:1206:1: error: the frame size of 1080 bytes is larger than 1024 bytes [-Werror=frame-larger-than=]
> drivers/staging/media/rkvdec/rkvdec-vp9.c:1042:1: error: the frame size of 1660 bytes is larger than 1024 bytes [-Werror=frame-larger-than=]
> drivers/staging/media/rkvdec/rkvdec-vp9.c:1042:1: error: the frame size of 2176 bytes is larger than 2048 bytes [-Werror=frame-larger-than=]
> drivers/staging/media/rkvdec/rkvdec-vp9.c:995:1: error: the frame size of 1656 bytes is larger than 1024 bytes [-Werror=frame-larger-than=]
>
>       Arnd



-- 
Thanks,
~Nick Desaulniers

Re: randconfig fixes for 5.10.y

[Greg KH]

On Tue, May 30, 2023 at 11:22:09AM +0300, Dan Carpenter wrote:
> I did some randconfig testing on 5.10.y and the following patches are
> required.
> 
> d7a7d721064c5 ("media: ti-vpe: cal: avoid FIELD_GET assertion")
> 42d95d1b3a9c6 ("drm/rcar: stop using 'imply' for dependencies")
> 
> The first patch is only required on 5.10.y.
> The second "drm/rcar" commit is required in 5.15.y as well.

Thanks, both now queued up.

greg k-h