On Fri, 2023-09-22 at 09:44 -0700, Mike Kravetz wrote:
>
> diff --git a/mm/hugetlb.c b/mm/hugetlb.c
> index f906c5fa4d09..8f3d5895fffc 100644
> --- a/mm/hugetlb.c
> +++ b/mm/hugetlb.c
> @@ -372,6 +372,11 @@ static void
> __hugetlb_vma_unlock_write_free(struct vm_area_struct *vma)
> struct hugetlb_vma_lock *vma_lock = vma-
> >vm_private_data;
>
> __hugetlb_vma_unlock_write_put(vma_lock);
> + } else if (__vma_private_lock(vma)) {
> + struct resv_map *resv_map = vma_resv_map(vma);
> +
> + /* no free for anon vmas, but still need to unlock */
> + up_write(&resv_map->rw_sema);
> }
> }
>
Nice catch. I'll add that.
I was still trying to reproduce the bug here.
The libhugetlbfs code compiles with the offending bits
commented out, but the misaligned_offset test wasn't
causing trouble on my test VM here.
Given the potential negative impact of moving from a
per-VMA lock to a per-backing-address_space lock, I'll
keep the 3 patches separate, and in the order they are
in now.
Let me go spin and test v2.
--
All Rights Reversed.
