Re: [kbuild-all] Re: arch/arm/boot/compressed/fdt_check_mem_start.c:62:10: warning: no previous prototype for function 'fdt_check_mem_start'

[Chen, Rong A]

On 8/21/2021 4:45 PM, Geert Uytterhoeven wrote:
> Dear Robot,
>
> On Sat, Aug 14, 2021 at 7:43 AM kernel test robot <lkp@xxxxxxxxx> wrote:
> > FYI, the error/warning still remains.
>
> Yes, and that's fine, as this function is never called from C code,
> only from assembler.


Hi Geert,

Thanks for the feedback, we'll ignore this warning.

Best Regards,
Rong Chen

> > tree:   https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
> > head:   dfa377c35d70c31139b1274ec49f87d380996c42
> > commit: 0673cb38951215060d7993b43ad3c45cd413c2c3 ARM: 9045/1: uncompress: Validate start of physical memory against passed DTB
> > date:   6 months ago
> > config: arm-randconfig-r003-20210814 (attached as .config)
> > compiler: clang version 14.0.0 (https://github.com/llvm/llvm-project 62df4df41c939205b2dc0a2a3bfb75b8c1ed74fa)
> > 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://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=0673cb38951215060d7993b43ad3c45cd413c2c3
> >          git remote add linus https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
> >          git fetch --no-tags linus master
> >          git checkout 0673cb38951215060d7993b43ad3c45cd413c2c3
> >          # save the attached .config to linux build tree
> >          COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=arm
> >
> > 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/arm/boot/compressed/fdt_check_mem_start.c:62:10: warning: no previous prototype for function 'fdt_check_mem_start' [-Wmissing-prototypes]
> >     uint32_t fdt_check_mem_start(uint32_t mem_start, const void *fdt)
> >              ^
> >     arch/arm/boot/compressed/fdt_check_mem_start.c:62:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
> >     uint32_t fdt_check_mem_start(uint32_t mem_start, const void *fdt)
> >     ^
> >     static
> >     1 warning generated.
> >
> >
> > vim +/fdt_check_mem_start +62 arch/arm/boot/compressed/fdt_check_mem_start.c
> >
> >      46
> >      47  /*
> >      48   * Check the start of physical memory
> >      49   *
> >      50   * Traditionally, the start address of physical memory is obtained by masking
> >      51   * the program counter.  However, this does require that this address is a
> >      52   * multiple of 128 MiB, precluding booting Linux on platforms where this
> >      53   * requirement is not fulfilled.
> >      54   * Hence validate the calculated address against the memory information in the
> >      55   * DTB, and, if out-of-range, replace it by the real start address.
> >      56   * To preserve backwards compatibility (systems reserving a block of memory
> >      57   * at the start of physical memory, kdump, ...), the traditional method is
> >      58   * always used if it yields a valid address.
> >      59   *
> >      60   * Return value: start address of physical memory to use
> >      61   */
> >    > 62  uint32_t fdt_check_mem_start(uint32_t mem_start, const void *fdt)
> >
> > ---
> > 0-DAY CI Kernel Test Service, Intel Corporation
> > https://lists.01.org/hyperkitty/list/kbuild-all@xxxxxxxxxxxx