Re: [PATCH] xfs: remove dead NULL check after __GFP_NOFAIL allocation

[Carlos Maiolino]

On Wed, Jun 24, 2026 at 09:51:55PM +0800, Gou Hao wrote:
> kmalloc with the __GFP_NOFAIL flag will never return NULL, so the
> subsequent ENOMEM check is unreachable dead code. Remove it.
> 
> Signed-off-by: Gou Hao <gouhao@xxxxxxxxxxxxx>

Looks fine.

Reviewed-by: Carlos Maiolino <cmaiolino@xxxxxxxxxx>


> ---
>  fs/xfs/libxfs/xfs_dir2.c     | 12 ------------
>  fs/xfs/libxfs/xfs_exchmaps.c |  5 -----
>  fs/xfs/xfs_buf.c             |  3 ---
>  fs/xfs/xfs_mru_cache.c       |  8 --------
>  4 files changed, 28 deletions(-)
> 
> diff --git a/fs/xfs/libxfs/xfs_dir2.c b/fs/xfs/libxfs/xfs_dir2.c
> index 0c0402a29b6b..6009ec26843d 100644
> --- a/fs/xfs/libxfs/xfs_dir2.c
> +++ b/fs/xfs/libxfs/xfs_dir2.c
> @@ -249,9 +249,6 @@ xfs_dir_init(
>  		return error;
>  
>  	args = kzalloc_obj(*args, GFP_KERNEL | __GFP_NOFAIL);
> -	if (!args)
> -		return -ENOMEM;
> -
>  	args->geo = dp->i_mount->m_dir_geo;
>  	args->dp = dp;
>  	args->trans = tp;
> @@ -342,9 +339,6 @@ xfs_dir_createname(
>  	}
>  
>  	args = kzalloc_obj(*args, GFP_KERNEL | __GFP_NOFAIL);
> -	if (!args)
> -		return -ENOMEM;
> -
>  	args->geo = dp->i_mount->m_dir_geo;
>  	args->name = name->name;
>  	args->namelen = name->len;
> @@ -503,9 +497,6 @@ xfs_dir_removename(
>  	XFS_STATS_INC(dp->i_mount, xs_dir_remove);
>  
>  	args = kzalloc_obj(*args, GFP_KERNEL | __GFP_NOFAIL);
> -	if (!args)
> -		return -ENOMEM;
> -
>  	args->geo = dp->i_mount->m_dir_geo;
>  	args->name = name->name;
>  	args->namelen = name->len;
> @@ -563,9 +554,6 @@ xfs_dir_replace(
>  		return rval;
>  
>  	args = kzalloc_obj(*args, GFP_KERNEL | __GFP_NOFAIL);
> -	if (!args)
> -		return -ENOMEM;
> -
>  	args->geo = dp->i_mount->m_dir_geo;
>  	args->name = name->name;
>  	args->namelen = name->len;
> diff --git a/fs/xfs/libxfs/xfs_exchmaps.c b/fs/xfs/libxfs/xfs_exchmaps.c
> index dcd0bd0b13b4..bd897676e38a 100644
> --- a/fs/xfs/libxfs/xfs_exchmaps.c
> +++ b/fs/xfs/libxfs/xfs_exchmaps.c
> @@ -500,11 +500,6 @@ xfs_exchmaps_link_to_sf(
>  	/* Read the current symlink target into a buffer. */
>  	buf = kmalloc(ip->i_disk_size + 1,
>  			GFP_KERNEL | __GFP_NOLOCKDEP | __GFP_NOFAIL);
> -	if (!buf) {
> -		ASSERT(0);
> -		return -ENOMEM;
> -	}
> -
>  	error = xfs_symlink_remote_read(ip, buf);
>  	if (error)
>  		goto free;
> diff --git a/fs/xfs/xfs_buf.c b/fs/xfs/xfs_buf.c
> index 3ce12fe1c307..5583139d7478 100644
> --- a/fs/xfs/xfs_buf.c
> +++ b/fs/xfs/xfs_buf.c
> @@ -130,9 +130,6 @@ xfs_buf_alloc_kmem(
>  	ASSERT(size < PAGE_SIZE);
>  
>  	bp->b_addr = kmalloc(size, gfp_mask | __GFP_NOFAIL);
> -	if (!bp->b_addr)
> -		return -ENOMEM;
> -
>  	/*
>  	 * Slab guarantees that we get back naturally aligned allocations for
>  	 * power of two sizes.  Keep this check as the canary in the coal mine
> diff --git a/fs/xfs/xfs_mru_cache.c b/fs/xfs/xfs_mru_cache.c
> index d61ec8cb126d..258c07da73e1 100644
> --- a/fs/xfs/xfs_mru_cache.c
> +++ b/fs/xfs/xfs_mru_cache.c
> @@ -334,18 +334,10 @@ xfs_mru_cache_create(
>  		return -EINVAL;
>  
>  	mru = kzalloc_obj(*mru, GFP_KERNEL | __GFP_NOFAIL);
> -	if (!mru)
> -		return -ENOMEM;
> -
>  	/* An extra list is needed to avoid reaping up to a grp_time early. */
>  	mru->grp_count = grp_count + 1;
>  	mru->lists = kzalloc(mru->grp_count * sizeof(*mru->lists),
>  				GFP_KERNEL | __GFP_NOFAIL);
> -	if (!mru->lists) {
> -		kfree(mru);
> -		return -ENOMEM;
> -	}
> -
>  	for (grp = 0; grp < mru->grp_count; grp++)
>  		INIT_LIST_HEAD(mru->lists + grp);
>  
> -- 
> 2.20.1
> 
>