Re: [kbuild-all] Re: [PATCH v2] mm: page_alloc: dump migrate-failed pages

[Rong Chen]

On 3/9/21 6:29 AM, Minchan Kim wrote:
> On Tue, Mar 09, 2021 at 05:29:30AM +0800, kernel test robot wrote:
> > Hi Minchan,
> >
> > I love your patch! Perhaps something to improve:
> >
> > [auto build test WARNING on hnaz-linux-mm/master]
> >
> > url:    https://github.com/0day-ci/linux/commits/Minchan-Kim/mm-page_alloc-dump-migrate-failed-pages/20210309-042205
> > base:   https://github.com/hnaz/linux-mm master
> > config: m68k-allmodconfig (attached as .config)
> > compiler: m68k-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
> >          # https://github.com/0day-ci/linux/commit/3c635af37b862e9c601ee8d5818f7da9cd3e2e57
> >          git remote add linux-review https://github.com/0day-ci/linux
> >          git fetch --no-tags linux-review Minchan-Kim/mm-page_alloc-dump-migrate-failed-pages/20210309-042205
> >          git checkout 3c635af37b862e9c601ee8d5818f7da9cd3e2e57
> >          # save the attached .config to linux build tree
> >          COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross ARCH=m68k
> >
> > If you fix the issue, kindly add following tag as appropriate
> > Reported-by: kernel test robot <lkp@xxxxxxxxx>
> >
> > All warnings (new ones prefixed by >>):
> >
> >     arch/m68k/include/asm/page_mm.h:169:49: warning: ordered comparison of pointer with null pointer [-Wextra]
> >       169 | #define virt_addr_valid(kaddr) ((void *)(kaddr) >= (void *)PAGE_OFFSET && (void *)(kaddr) < high_memory)
> >           |                                                 ^~
> >     include/linux/compiler.h:78:42: note: in definition of macro 'unlikely'
> >        78 | # define unlikely(x) __builtin_expect(!!(x), 0)
> >           |                                          ^
> >     include/linux/scatterlist.h:143:2: note: in expansion of macro 'BUG_ON'
> >       143 |  BUG_ON(!virt_addr_valid(buf));
> >           |  ^~~~~~
> >     include/linux/scatterlist.h:143:10: note: in expansion of macro 'virt_addr_valid'
> >       143 |  BUG_ON(!virt_addr_valid(buf));
> >           |          ^~~~~~~~~~~~~~~
> >     In file included from arch/m68k/include/asm/page.h:60,
> >                      from arch/m68k/include/asm/thread_info.h:6,
> >                      from include/linux/thread_info.h:38,
> >                      from include/asm-generic/preempt.h:5,
> >                      from ./arch/m68k/include/generated/asm/preempt.h:1,
> >                      from include/linux/preempt.h:78,
> >                      from include/linux/spinlock.h:51,
> >                      from include/linux/mmzone.h:8,
> >                      from include/linux/gfp.h:6,
> >                      from include/linux/mm.h:10,
> >                      from mm/page_alloc.c:19:
> I am not sure this is triggered by the patch since I could see the
> warn with reverting the patch.

Hi Minchan,

Only the lines prefixed by ">>" are related with the patch:

> > mm/page_alloc.c:8348:5: warning: no previous prototype for 'alloc_contig_ratelimit' [-Wmissing-prototypes]

    8348 | int alloc_contig_ratelimit(void)
         |     ^~~~~~~~~~~~~~~~~~~~~~

> > mm/page_alloc.c:8353:6: warning: no previous prototype for 'dump_migrate_failure_pages' [-Wmissing-prototypes]

    8353 | void dump_migrate_failure_pages(struct list_head *page_list)



Best Regards,
Rong Chen