[PATCH v4 11/14] mm/hugetlbfs: update hugetlbfs to use mmap_prepare

[Sumanth Korikkar]

On Tue, Sep 23, 2025 at 02:17:04PM -0700, Andrew Morton wrote:
> On Tue, 23 Sep 2025 13:52:09 +0200 Sumanth Korikkar <sumanthk at linux.ibm.com> wrote:
> 
> > > --- a/fs/hugetlbfs/inode.c
> > > +++ b/fs/hugetlbfs/inode.c
> > > @@ -96,8 +96,15 @@ static const struct fs_parameter_spec hugetlb_fs_parameters[] = {
> > >  #define PGOFF_LOFFT_MAX \
> > >  	(((1UL << (PAGE_SHIFT + 1)) - 1) <<  (BITS_PER_LONG - (PAGE_SHIFT + 1)))
> > >  
> > > -static int hugetlbfs_file_mmap(struct file *file, struct vm_area_struct *vma)
> > > +static int hugetlb_file_mmap_prepare_success(const struct vm_area_struct *vma)
> > >  {
> > > +	/* Unfortunate we have to reassign vma->vm_private_data. */
> > > +	return hugetlb_vma_lock_alloc((struct vm_area_struct *)vma);
> > > +}
> > 
> > Hi Lorenzo,
> > 
> > The following tests causes the kernel to enter a blocked state,
> > suggesting an issue related to locking order. I was able to reproduce
> > this behavior in certain test runs.
> 
> Thanks.  I pulled this series out of mm.git's mm-stable branch, put it
> back into mm-unstable.

Hi all,

The issue is reproducible again in linux-next with the following commit:
5fdb155933fa ("mm/hugetlbfs: update hugetlbfs to use mmap_prepare")

Thanks,
Sumanth