Re: [akpm-mm:mm-stable 219/240] mm/memory.c:5410:41: error: implicit declaration of function 'vma_is_tcp'; did you mean 'vma_is_dax'?

[Suren Baghdasaryan <surenb@google.com>]

On Sun, Aug 13, 2023 at 1:17 AM kernel test robot <lkp@intel.com> wrote:
>
> tree:   https://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm.git mm-stable
> head:   5fb2ea3111f4ecc6dc4891ce5b00f0217aae9a04
> commit: 4aaa60dad4d1c96151dec51098aed866bb6e867d [219/240] mm: allow per-VMA locks on file-backed VMAs
> config: x86_64-defconfig (https://download.01.org/0day-ci/archive/20230813/202308131610.jF4ncWp6-lkp@intel.com/config)
> compiler: gcc-12 (Debian 12.2.0-14) 12.2.0
> reproduce: (https://download.01.org/0day-ci/archive/20230813/202308131610.jF4ncWp6-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/202308131610.jF4ncWp6-lkp@intel.com/
>
> All errors (new ones prefixed by >>):
>
>    In file included from include/linux/build_bug.h:5,
>                     from include/linux/container_of.h:5,
>                     from include/linux/list.h:5,
>                     from include/linux/smp.h:12,
>                     from include/linux/kernel_stat.h:5,
>                     from mm/memory.c:42:
>    mm/memory.c: In function 'lock_vma_under_rcu':
> >> mm/memory.c:5410:41: error: implicit declaration of function 'vma_is_tcp'; did you mean 'vma_is_dax'? [-Werror=implicit-function-declaration]
>     5410 |         if (unlikely(!vma->anon_vma && !vma_is_tcp(vma)))
>          |                                         ^~~~~~~~~~
>    include/linux/compiler.h:77:45: note: in definition of macro 'unlikely'
>       77 | # define unlikely(x)    __builtin_expect(!!(x), 0)
>          |                                             ^
>    cc1: some warnings being treated as errors

Same issue as https://lore.kernel.org/all/202308121909.XNYBtqNI-lkp@intel.com/
with the same fix that Matthew suggested.

>
>
> vim +5410 mm/memory.c
>
> c2508ec5a58db6 Linus Torvalds     2023-06-15  5382
> 50ee3253720614 Suren Baghdasaryan 2023-02-27  5383  #ifdef CONFIG_PER_VMA_LOCK
> 50ee3253720614 Suren Baghdasaryan 2023-02-27  5384  /*
> 50ee3253720614 Suren Baghdasaryan 2023-02-27  5385   * Lookup and lock a VMA under RCU protection. Returned VMA is guaranteed to be
> 50ee3253720614 Suren Baghdasaryan 2023-02-27  5386   * stable and not isolated. If the VMA is not found or is being modified the
> 50ee3253720614 Suren Baghdasaryan 2023-02-27  5387   * function returns NULL.
> 50ee3253720614 Suren Baghdasaryan 2023-02-27  5388   */
> 50ee3253720614 Suren Baghdasaryan 2023-02-27  5389  struct vm_area_struct *lock_vma_under_rcu(struct mm_struct *mm,
> 50ee3253720614 Suren Baghdasaryan 2023-02-27  5390                                        unsigned long address)
> 50ee3253720614 Suren Baghdasaryan 2023-02-27  5391  {
> 50ee3253720614 Suren Baghdasaryan 2023-02-27  5392      MA_STATE(mas, &mm->mm_mt, address, address);
> 50ee3253720614 Suren Baghdasaryan 2023-02-27  5393      struct vm_area_struct *vma;
> 50ee3253720614 Suren Baghdasaryan 2023-02-27  5394
> 50ee3253720614 Suren Baghdasaryan 2023-02-27  5395      rcu_read_lock();
> 50ee3253720614 Suren Baghdasaryan 2023-02-27  5396  retry:
> 50ee3253720614 Suren Baghdasaryan 2023-02-27  5397      vma = mas_walk(&mas);
> 50ee3253720614 Suren Baghdasaryan 2023-02-27  5398      if (!vma)
> 50ee3253720614 Suren Baghdasaryan 2023-02-27  5399              goto inval;
> 50ee3253720614 Suren Baghdasaryan 2023-02-27  5400
> 50ee3253720614 Suren Baghdasaryan 2023-02-27  5401      if (!vma_start_read(vma))
> 50ee3253720614 Suren Baghdasaryan 2023-02-27  5402              goto inval;
> 50ee3253720614 Suren Baghdasaryan 2023-02-27  5403
> 657b5146955eba Jann Horn          2023-07-26  5404      /*
> 657b5146955eba Jann Horn          2023-07-26  5405       * find_mergeable_anon_vma uses adjacent vmas which are not locked.
> 657b5146955eba Jann Horn          2023-07-26  5406       * This check must happen after vma_start_read(); otherwise, a
> 657b5146955eba Jann Horn          2023-07-26  5407       * concurrent mremap() with MREMAP_DONTUNMAP could dissociate the VMA
> 657b5146955eba Jann Horn          2023-07-26  5408       * from its anon_vma.
> 657b5146955eba Jann Horn          2023-07-26  5409       */
> 657b5146955eba Jann Horn          2023-07-26 @5410      if (unlikely(!vma->anon_vma && !vma_is_tcp(vma)))
> 657b5146955eba Jann Horn          2023-07-26  5411              goto inval_end_read;
> 657b5146955eba Jann Horn          2023-07-26  5412
> 444eeb17437a0e Suren Baghdasaryan 2023-02-27  5413      /*
> 444eeb17437a0e Suren Baghdasaryan 2023-02-27  5414       * Due to the possibility of userfault handler dropping mmap_lock, avoid
> 444eeb17437a0e Suren Baghdasaryan 2023-02-27  5415       * it for now and fall back to page fault handling under mmap_lock.
> 444eeb17437a0e Suren Baghdasaryan 2023-02-27  5416       */
> 657b5146955eba Jann Horn          2023-07-26  5417      if (userfaultfd_armed(vma))
> 657b5146955eba Jann Horn          2023-07-26  5418              goto inval_end_read;
> 444eeb17437a0e Suren Baghdasaryan 2023-02-27  5419
> 50ee3253720614 Suren Baghdasaryan 2023-02-27  5420      /* Check since vm_start/vm_end might change before we lock the VMA */
> 657b5146955eba Jann Horn          2023-07-26  5421      if (unlikely(address < vma->vm_start || address >= vma->vm_end))
> 657b5146955eba Jann Horn          2023-07-26  5422              goto inval_end_read;
> 50ee3253720614 Suren Baghdasaryan 2023-02-27  5423
> 50ee3253720614 Suren Baghdasaryan 2023-02-27  5424      /* Check if the VMA got isolated after we found it */
> 50ee3253720614 Suren Baghdasaryan 2023-02-27  5425      if (vma->detached) {
> 50ee3253720614 Suren Baghdasaryan 2023-02-27  5426              vma_end_read(vma);
> 52f238653e452e Suren Baghdasaryan 2023-02-27  5427              count_vm_vma_lock_event(VMA_LOCK_MISS);
> 50ee3253720614 Suren Baghdasaryan 2023-02-27  5428              /* The area was replaced with another one */
> 50ee3253720614 Suren Baghdasaryan 2023-02-27  5429              goto retry;
> 50ee3253720614 Suren Baghdasaryan 2023-02-27  5430      }
> 50ee3253720614 Suren Baghdasaryan 2023-02-27  5431
> 50ee3253720614 Suren Baghdasaryan 2023-02-27  5432      rcu_read_unlock();
> 50ee3253720614 Suren Baghdasaryan 2023-02-27  5433      return vma;
> 657b5146955eba Jann Horn          2023-07-26  5434
> 657b5146955eba Jann Horn          2023-07-26  5435  inval_end_read:
> 657b5146955eba Jann Horn          2023-07-26  5436      vma_end_read(vma);
> 50ee3253720614 Suren Baghdasaryan 2023-02-27  5437  inval:
> 50ee3253720614 Suren Baghdasaryan 2023-02-27  5438      rcu_read_unlock();
> 52f238653e452e Suren Baghdasaryan 2023-02-27  5439      count_vm_vma_lock_event(VMA_LOCK_ABORT);
> 50ee3253720614 Suren Baghdasaryan 2023-02-27  5440      return NULL;
> 50ee3253720614 Suren Baghdasaryan 2023-02-27  5441  }
> 50ee3253720614 Suren Baghdasaryan 2023-02-27  5442  #endif /* CONFIG_PER_VMA_LOCK */
> 50ee3253720614 Suren Baghdasaryan 2023-02-27  5443
>
> :::::: The code at line 5410 was first introduced by commit
> :::::: 657b5146955eba331e01b9a6ae89ce2e716ba306 mm: lock_vma_under_rcu() must check vma->anon_vma under vma lock
>
> :::::: TO: Jann Horn <jannh@google.com>
> :::::: CC: Linus Torvalds <torvalds@linux-foundation.org>
>
> --
> 0-DAY CI Kernel Test Service
> https://github.com/intel/lkp-tests/wiki