Re: undefined reference to `start_isolate_page_range'

From: Randy Dunlap
Date: Mon Sep 07 2020 - 18:40:24 EST


Hi lkp, (or is it ktr?)

This is sort of a shame-on-you post. As a robot, I hope that you
don't have any hard feelings about it. :)


On 9/6/20 9:17 AM, kernel test robot wrote:
> Hi Michal,
>
> FYI, the error/warning still remains.
>
> tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
> head: dd9fb9bb3340c791a2be106fdc895db75f177343
> commit: 2602276d3d3811b1a48c48113042cd75fcbfc27d microblaze: Wire CMA allocator
> date: 7 months ago
> config: microblaze-randconfig-r021-20200906 (attached as .config)
> compiler: microblaze-linux-gcc (GCC) 9.3.0
> reproduce (this is a W=1 build):
> wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
> chmod +x ~/bin/make.cross
> git checkout 2602276d3d3811b1a48c48113042cd75fcbfc27d
> # save the attached .config to linux build tree
> COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross ARCH=microblaze
>
> If you fix the issue, kindly add following tag as appropriate
> Reported-by: kernel test robot <lkp@xxxxxxxxx>
>
> All errors (new ones prefixed by >>):
>
> microblaze-linux-ld: mm/page_alloc.o: in function `alloc_contig_range':
>>> (.text+0x10c8c): undefined reference to `start_isolate_page_range'
>>> microblaze-linux-ld: (.text+0x10f14): undefined reference to `test_pages_isolated'
>>> microblaze-linux-ld: (.text+0x10fd0): undefined reference to `undo_isolate_page_range'

When I (easily) reproduce this build error, I also see a Kconfig warning:
(or the same warning repeated 3 times)

WARNING: unmet direct dependencies detected for CMA
Depends on [n]: MMU [=n]
Selected by [m]:
- DRM_ASPEED_GFX [=m] && HAS_IOMEM [=y] && DRM [=m] && OF [=y] && (COMPILE_TEST [=y] || ARCH_ASPEED) && HAVE_DMA_CONTIGUOUS [=y]

WARNING: unmet direct dependencies detected for CMA
Depends on [n]: MMU [=n]
Selected by [m]:
- DRM_ASPEED_GFX [=m] && HAS_IOMEM [=y] && DRM [=m] && OF [=y] && (COMPILE_TEST [=y] || ARCH_ASPEED) && HAVE_DMA_CONTIGUOUS [=y]

WARNING: unmet direct dependencies detected for CMA
Depends on [n]: MMU [=n]
Selected by [m]:
- DRM_ASPEED_GFX [=m] && HAS_IOMEM [=y] && DRM [=m] && OF [=y] && (COMPILE_TEST [=y] || ARCH_ASPEED) && HAVE_DMA_CONTIGUOUS [=y]


This is the cause of the build errors.
You shouldn't omit Kconfig warnings from your reports.

> ---
> 0-DAY CI Kernel Test Service, Intel Corporation
> https://lists.01.org/hyperkitty/list/kbuild-all@xxxxxxxxxxxx


cheers.
--
~Randy