Re: [PATCH mm-unstable 3/9] mm/madvise: add file and shmem support to MADV_COLLAPSE

["Zach O'Keefe" <zokeefe@google.com>]

On Sun, Aug 14, 2022 at 10:41 PM kernel test robot <lkp@intel.com> wrote:
>
> Hi Zach,
>
> Thank you for the patch! Yet something to improve:
>
> [auto build test ERROR on akpm-mm/mm-everything]
>
> url:    https://github.com/intel-lab-lkp/linux/commits/Zach-O-Keefe/mm-add-file-shmem-support-to-MADV_COLLAPSE/20220812-093122
> base:   https://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm.git mm-everything
> config: i386-allyesconfig (https://download.01.org/0day-ci/archive/20220815/202208151331.uxreCJWj-lkp@intel.com/config)
> compiler: gcc-11 (Debian 11.3.0-3) 11.3.0
> reproduce (this is a W=1 build):
>         # https://github.com/intel-lab-lkp/linux/commit/dff08746d6f7b9387b94360b66bd9db644542991
>         git remote add linux-review https://github.com/intel-lab-lkp/linux
>         git fetch --no-tags linux-review Zach-O-Keefe/mm-add-file-shmem-support-to-MADV_COLLAPSE/20220812-093122
>         git checkout dff08746d6f7b9387b94360b66bd9db644542991
>         # save the config file
>         mkdir build_dir && cp config build_dir/.config
>         make W=1 O=build_dir ARCH=i386 SHELL=/bin/bash
>
> If you fix the issue, kindly add following tag where applicable
> Reported-by: kernel test robot <lkp@intel.com>
>
> All errors (new ones prefixed by >>):
>
>    mm/khugepaged.c: In function 'set_huge_pmd':
> >> mm/khugepaged.c:1403:13: error: assignment of read-only variable 'vmf'
>     1403 |         vmf = (struct vm_fault) {
>          |             ^
>
>
> vim +/vmf +1403 mm/khugepaged.c
>
>   1393
>   1394  /* hpage must be locked, and mmap_lock must be held in write */
>   1395  static int set_huge_pmd(struct vm_area_struct *vma, unsigned long addr,
>   1396                          pmd_t *pmdp, struct page *hpage)
>   1397  {
>   1398          struct vm_fault vmf;
>   1399
>   1400          VM_BUG_ON(!PageTransHuge(hpage));
>   1401          mmap_assert_write_locked(vma->vm_mm);
>   1402
> > 1403          vmf = (struct vm_fault) {
>   1404                  .vma = vma,
>   1405                  .address = addr,
>   1406                  .flags = 0,
>   1407                  .pmd = pmdp,
>   1408          };
>   1409
>   1410          if (do_set_pmd(&vmf, hpage))
>   1411                  return SCAN_FAIL;
>   1412
>   1413          get_page(hpage);
>   1414          return SCAN_SUCCEED;
>   1415  }
>   1416
>
> --
> 0-DAY CI Kernel Test Service
> https://01.org/lkp
>

Thanks lkp & apologies here. Anticipating at least one successive
version and will include the fixes there.