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

Alistair Popple <[email protected]> Mon, 27 Jul 2026 11:41:27 +1000

Newsgroups	org.kernel.vger.linux-rdma,org.kernel.vger.linux-kernel,org.kvack.linux-mm,org.ozlabs.lists.linuxppc-dev
Message-ID	<[email protected]>

On 2026-07-24 at 12:28 +1000, Gou Hao <[email protected]> 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 <[email protected]>

> Signed-off-by: Gou Hao <[email protected]>
> ---
>  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
> 
>