[linux-next:master 3972/6402] kernel/dma/pool.o: warning: objtool: __llvm_gcov_writeout()+0x14: call without frame pointer save/setup

[linux-next:master 3972/6402] kernel/dma/pool.o: warning: objtool: __llvm_gcov_writeout()+0x14: call without frame pointer save/setup

[kbuild test robot]

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tree:   https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git master
head:   dfd71d381f7e1aa118e0368774aa05f5c4a48870
commit: 82fef0ad811fb5976cf36ccc3d2c3bc0195dfb72 [3972/6402] x86/mm: unencrypted non-blocking DMA allocations use coherent pools
config: x86_64-randconfig-d001-20200502 (attached as .config)
compiler: clang version 11.0.0 (https://github.com/llvm/llvm-project 45b7d44ecb01780e26dc8d3c30bc34e32c08dd70)
reproduce:
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # install x86_64 cross compiling tool for clang build
        # apt-get install binutils-x86-64-linux-gnu
        git checkout 82fef0ad811fb5976cf36ccc3d2c3bc0195dfb72
        # save the attached .config to linux build tree
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=x86_64 

If you fix the issue, kindly add following tag as appropriate
Reported-by: kbuild test robot <lkp@intel.com>

All warnings (new ones prefixed by >>):

>> kernel/dma/pool.o: warning: objtool: __llvm_gcov_writeout()+0x14: call without frame pointer save/setup
>> kernel/dma/pool.o: warning: objtool: __llvm_gcov_flush()+0x0: call without frame pointer save/setup
--
>> kernel/dma/remap.o: warning: objtool: __llvm_gcov_writeout()+0x14: call without frame pointer save/setup
>> kernel/dma/remap.o: warning: objtool: __llvm_gcov_flush()+0x0: call without frame pointer save/setup

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all(a)lists.01.org

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Re: [linux-next:master 3972/6402] kernel/dma/pool.o: warning: objtool: __llvm_gcov_writeout()+0x14: call without frame pointer save/setup

[David Rientjes]

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On Tue, 5 May 2020, kbuild test robot wrote:

> tree:   https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git master
> head:   dfd71d381f7e1aa118e0368774aa05f5c4a48870
> commit: 82fef0ad811fb5976cf36ccc3d2c3bc0195dfb72 [3972/6402] x86/mm: unencrypted non-blocking DMA allocations use coherent pools
> config: x86_64-randconfig-d001-20200502 (attached as .config)
> compiler: clang version 11.0.0 (https://github.com/llvm/llvm-project 45b7d44ecb01780e26dc8d3c30bc34e32c08dd70)
> reproduce:
>         wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
>         chmod +x ~/bin/make.cross
>         # install x86_64 cross compiling tool for clang build
>         # apt-get install binutils-x86-64-linux-gnu
>         git checkout 82fef0ad811fb5976cf36ccc3d2c3bc0195dfb72
>         # save the attached .config to linux build tree
>         COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=x86_64 
> 
> If you fix the issue, kindly add following tag as appropriate
> Reported-by: kbuild test robot <lkp@intel.com>
> 
> All warnings (new ones prefixed by >>):
> 
> >> kernel/dma/pool.o: warning: objtool: __llvm_gcov_writeout()+0x14: call without frame pointer save/setup
> >> kernel/dma/pool.o: warning: objtool: __llvm_gcov_flush()+0x0: call without frame pointer save/setup
> --
> >> kernel/dma/remap.o: warning: objtool: __llvm_gcov_writeout()+0x14: call without frame pointer save/setup
> >> kernel/dma/remap.o: warning: objtool: __llvm_gcov_flush()+0x0: call without frame pointer save/setup
> 

At commit 82fef0ad811f ("x86/mm: unencrypted non-blocking DMA allocations 
use coherent pools") there should be no new kernel/dma/remap.o warnings, 
the Kconfig is merely selecting DMA_COHERENT_POOL.  The patch series 
actually only removed code from kernel/dma/remap.c, it did not add any 
code :)

Since there are tons of warnings all over the kernel when building with 
this .config (probably because of CONFIG_FRAME_POINTER) I assume this is 
unrelated to this particular series or anything that gets introduced in 
dma-mapping.git.

Re: [linux-next:master 3972/6402] kernel/dma/pool.o: warning: objtool: __llvm_gcov_writeout()+0x14: call without frame pointer save/setup

[Nick Desaulniers]

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On Tue, May 5, 2020 at 11:19 AM 'David Rientjes' via Clang Built Linux
<clang-built-linux@googlegroups.com> wrote:
>
> On Tue, 5 May 2020, kbuild test robot wrote:
>
> > tree:   https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git master
> > head:   dfd71d381f7e1aa118e0368774aa05f5c4a48870
> > commit: 82fef0ad811fb5976cf36ccc3d2c3bc0195dfb72 [3972/6402] x86/mm: unencrypted non-blocking DMA allocations use coherent pools
> > config: x86_64-randconfig-d001-20200502 (attached as .config)
> > compiler: clang version 11.0.0 (https://github.com/llvm/llvm-project 45b7d44ecb01780e26dc8d3c30bc34e32c08dd70)
> > reproduce:
> >         wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
> >         chmod +x ~/bin/make.cross
> >         # install x86_64 cross compiling tool for clang build
> >         # apt-get install binutils-x86-64-linux-gnu
> >         git checkout 82fef0ad811fb5976cf36ccc3d2c3bc0195dfb72
> >         # save the attached .config to linux build tree
> >         COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=x86_64
> >
> > If you fix the issue, kindly add following tag as appropriate
> > Reported-by: kbuild test robot <lkp@intel.com>
> >
> > All warnings (new ones prefixed by >>):
> >
> > >> kernel/dma/pool.o: warning: objtool: __llvm_gcov_writeout()+0x14: call without frame pointer save/setup
> > >> kernel/dma/pool.o: warning: objtool: __llvm_gcov_flush()+0x0: call without frame pointer save/setup
> > --
> > >> kernel/dma/remap.o: warning: objtool: __llvm_gcov_writeout()+0x14: call without frame pointer save/setup
> > >> kernel/dma/remap.o: warning: objtool: __llvm_gcov_flush()+0x0: call without frame pointer save/setup
> >
>
> At commit 82fef0ad811f ("x86/mm: unencrypted non-blocking DMA allocations
> use coherent pools") there should be no new kernel/dma/remap.o warnings,
> the Kconfig is merely selecting DMA_COHERENT_POOL.  The patch series
> actually only removed code from kernel/dma/remap.c, it did not add any
> code :)
>
> Since there are tons of warnings all over the kernel when building with
> this .config (probably because of CONFIG_FRAME_POINTER) I assume this is
> unrelated to this particular series or anything that gets introduced in
> dma-mapping.git.

Yes, this is an unrelated known issue, sorry.
https://github.com/ClangBuiltLinux/linux/issues/955
(We just got clang builds turned on 0day bot, and are now being
drowned in build reports from randconfigs we hadn't previously found.
Which is both good (what I want), and bad (what I don't have time to
fix all the different reports)).

-- 
Thanks,
~Nick Desaulniers