Re: arch/mips/include/asm/mach-ip27/topology.h:19:7: error: implicit declaration of function 'hub_data'

[Mike Rapoport <rppt@linux.ibm.com>]

Hi,

On Tue, Aug 04, 2020 at 01:39:14AM +0800, kernel test robot wrote:
> Hi Mike,
> 
> FYI, the error/warning still remains.
> 
> tree:   https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
> head:   bcf876870b95592b52519ed4aafcf9d95999bc9c
> commit: 397dc00e249ec64e106374565575dd0eb7e25998 mips: sgi-ip27: switch from DISCONTIGMEM to SPARSEMEM
> date:   10 months ago
> config: mips-randconfig-r032-20200803 (attached as .config)
> compiler: mips64-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 397dc00e249ec64e106374565575dd0eb7e25998
>         # save the attached .config to linux build tree
>         COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross ARCH=mips 
> 
> If you fix the issue, kindly add following tag as appropriate
> Reported-by: kernel test robot <lkp@intel.com>
> 
> All errors (new ones prefixed by >>):
> 
>    In file included from arch/mips/include/asm/topology.h:11,
>                     from include/linux/topology.h:36,
>                     from include/linux/gfp.h:9,
>                     from include/linux/slab.h:15,
>                     from include/linux/crypto.h:19,
>                     from include/crypto/hash.h:11,
>                     from include/linux/uio.h:10,
>                     from include/linux/socket.h:8,
>                     from include/linux/compat.h:15,
>                     from arch/mips/kernel/asm-offsets.c:12:
>    arch/mips/include/asm/mach-ip27/topology.h:25:39: error: 'MAX_COMPACT_NODES' undeclared here (not in a function)
>       25 | extern unsigned char __node_distances[MAX_COMPACT_NODES][MAX_COMPACT_NODES];
>          |                                       ^~~~~~~~~~~~~~~~~
>    include/linux/topology.h: In function 'numa_node_id':
> >> arch/mips/include/asm/mach-ip27/topology.h:16:27: error: implicit declaration of function 'cputonasid' [-Werror=implicit-function-declaration]
>       16 | #define cpu_to_node(cpu) (cputonasid(cpu))
>          |                           ^~~~~~~~~~

This happens when randconfig disables NUMA and has SGI_IP27 enabled.
Before switch from discontigmem to sparsemem, there always was
CONFIG_NEED_MULTIPLE_NODES=y because it was selected by DISCONTIGMEM.
Without DISCONTIGMEM it is possible to have SPARSEMEM without NUMA for
SGI_IP27 and as many things there rely on custom node definition, the
build breaks.

I don't remember small Origin or Onyx systems so I think it would be
reasonable to make SGI_IP27 to select NUMA. If the below patch makes
sense I'll resend it formally.

diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig
index 6fee1a133e9d..a7e40bb1e5bc 100644
--- a/arch/mips/Kconfig
+++ b/arch/mips/Kconfig
@@ -678,6 +678,7 @@ config SGI_IP27
 	select SYS_SUPPORTS_NUMA
 	select SYS_SUPPORTS_SMP
 	select MIPS_L1_CACHE_SHIFT_7
+	select NUMA
 	help
 	  This are the SGI Origin 200, Origin 2000 and Onyx 2 Graphics
 	  workstations.  To compile a Linux kernel that runs on these, say Y


-- 
Sincerely yours,
Mike.