Re: [linux-next:master 8777/13479] mm/hugetlb.c:3095:39: warning: array subscript 4294967295 is above array bounds of 'struct list_head[1]'

[Andrew Morton <akpm@linux-foundation.org>]

On Fri, 07 Aug 2026 05:01:04 +0800 kernel test robot <lkp@intel.com> wrote:

> tree:   https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git master
> head:   ea2bff00da89d7767d677bb68470130ba96f4928
> commit: 20549ccf4da49ff6dcb35ffc741f92aa92e07aeb [8777/13479] mm/hugetlb: free cross-zone bootmem gigantic pages after allocation
> config: parisc-randconfig-002-20260807 (https://download.01.org/0day-ci/archive/20260807/202608070433.x3vNSfjt-lkp@intel.com/config)
> compiler: hppa-linux-gcc (GCC) 8.5.0

Such an old compiler.

> reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20260807/202608070433.x3vNSfjt-lkp@intel.com/reproduce)
> 
> If you fix the issue in a separate patch/commit (i.e. not just a new version of
> the same patch/commit), kindly add following tags
> | Reported-by: kernel test robot <lkp@intel.com>
> | Closes: https://lore.kernel.org/oe-kbuild-all/202608070433.x3vNSfjt-lkp@intel.com/
> 
> All warnings (new ones prefixed by >>):
> 
>    mm/hugetlb.c: In function 'alloc_bootmem_huge_page':
> >> mm/hugetlb.c:3095:39: warning: array subscript 4294967295 is above array bounds of 'struct list_head[1]' [-Warray-bounds]
>        list_add(&m->list, &huge_boot_pages[nid_request]);
>                            ~~~~~~~~~~~~~~~^~~~~~~~~~~~~
>    In file included from mm/hugetlb.c:6:
> >> include/linux/list.h:163:12: warning: array subscript -1 is below array bounds of 'struct list_head[1]' [-Warray-bounds]
>      new->prev = prev;
>      ~~~~~~~~~~^~~~~~

Well crap, that patch has been in there since June 12.

I can't reproduce it with the provided config and hppa-linux gcc-16.1.0.

Muchun, I'd be inclined to pretend we never saw this.  But if you want
to address it, please do a patch against mm-stable with

Fixes: 20549ccf4da4 ("mm/hugetlb: free cross-zone bootmem gigantic pages after allocation")