[Devel] [PATCH VZ9] fs/fuse kio: Use kvcalloc to prevent failure in fragmented systems

[Alexey Kuznetsov]

Acknowledged

On Fri, Aug 1, 2025 at 8:56 PM Liu Kui <kui.liu at virtuozzo.com> wrote:
>
> Address large memory allocation failure by replacing kcalloc with
> kvcalloc. This allows fallback to vmalloc for large allocations,
> as virtually contiguous meomory is sufficient here, improving
> reliability in highly fragmented systems
>
> Related to: #VSTOR-112413
> https://virtuozzo.atlassian.net/browse/VSTOR-112413
>
> Signed-off-by: Liu Kui <kui.liu at virtuozzo.com>
> ---
>  fs/fuse/kio/pcs/pcs_mr.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/fs/fuse/kio/pcs/pcs_mr.c b/fs/fuse/kio/pcs/pcs_mr.c
> index cbd3b440dd1b..28e04d1b2639 100644
> --- a/fs/fuse/kio/pcs/pcs_mr.c
> +++ b/fs/fuse/kio/pcs/pcs_mr.c
> @@ -17,7 +17,7 @@ void pcs_umem_release(struct pcs_umem *umem)
>         unpin_user_pages(umem->pages, umem->npages);
>         atomic64_sub(umem->npages, &mm_s->pinned_vm);
>         mmdrop(mm_s);
> -       kfree(umem->pages);
> +       kvfree(umem->pages);
>         kfree(umem);
>  }
>
> @@ -48,7 +48,7 @@ struct pcs_umem *pcs_umem_get(u64 start, u64 len)
>         mmap_read_lock(mm_s);
>
>         umem->fp_addr = fp_va;
> -       umem->pages = kcalloc(npages, sizeof(struct page *), GFP_KERNEL);
> +       umem->pages = kvcalloc(npages, sizeof(struct page *), GFP_KERNEL);
>         if (!umem->pages) {
>                 ret = -ENOMEM;
>                 goto out_err;
> --
> 2.39.5 (Apple Git-154)