Re: [PATCH v2 5/6] lib/test_hmm: remove dead NULL checks after GFP_NOFAIL allocations

From: Alistair Popple

Date: Sun Jul 26 2026 - 21:42:00 EST


On 2026-07-24 at 12:28 +1000, Gou Hao <gouhao@xxxxxxxxxxxxx> wrote...
> kvcalloc with the __GFP_NOFAIL flag will never return NULL, so the
> subsequent NULL checks are unreachable dead code. Remove them.

Reviewed-by: Alistair Popple <apopple@xxxxxxxxxx>

> Signed-off-by: Gou Hao <gouhao@xxxxxxxxxxxxx>
> ---
> lib/test_hmm.c | 6 ------
> 1 file changed, 6 deletions(-)
>
> diff --git a/lib/test_hmm.c b/lib/test_hmm.c
> index 9c59d1ceb5b57..d615e4e5fc447 100644
> --- a/lib/test_hmm.c
> +++ b/lib/test_hmm.c
> @@ -1209,16 +1209,10 @@ static int dmirror_migrate_to_device(struct dmirror *dmirror,
> if (!mmget_not_zero(mm))
> return -EINVAL;
>
> - ret = -ENOMEM;
> src_pfns = kvcalloc(PTRS_PER_PTE, sizeof(*src_pfns),
> GFP_KERNEL | __GFP_NOFAIL);
> - if (!src_pfns)
> - goto free_mem;
> -
> dst_pfns = kvcalloc(PTRS_PER_PTE, sizeof(*dst_pfns),
> GFP_KERNEL | __GFP_NOFAIL);
> - if (!dst_pfns)
> - goto free_mem;
>
> ret = 0;
> mmap_read_lock(mm);
> --
> 2.20.1
>
>