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Date: Tue, 23 Sep 2025 14:17:04 -0700
From: Andrew Morton <akpm@linux-foundation.org>
To: Sumanth Korikkar <sumanthk@linux.ibm.com>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>, Jonathan Corbet
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Subject: Re: [PATCH v4 11/14] mm/hugetlbfs: update hugetlbfs to use
 mmap_prepare
Message-Id: <20250923141704.90fba5bdf8c790e0496e6ac1@linux-foundation.org>
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References: <cover.1758135681.git.lorenzo.stoakes@oracle.com>
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On Tue, 23 Sep 2025 13:52:09 +0200 Sumanth Korikkar <sumanthk@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.