Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::3:5 as permitted sender) client-ip=2620:137:e000::3:5;
From:   fan <nifan.cxl@gmail.com>
Date:   Mon, 6 Nov 2023 10:54:38 -0800
To:     Vishal Verma <vishal.l.verma@intel.com>
Cc:     Andrew Morton <akpm@linux-foundation.org>,
        David Hildenbrand <david@redhat.com>,
        Oscar Salvador <osalvador@suse.de>,
        Dan Williams <dan.j.williams@intel.com>,
        Dave Jiang <dave.jiang@intel.com>,
        linux-kernel@vger.kernel.org, linux-mm@kvack.org,
        nvdimm@lists.linux.dev, linux-cxl@vger.kernel.org,
        Huang Ying <ying.huang@intel.com>,
        Dave Hansen <dave.hansen@linux.intel.com>,
        "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com>,
        Michal Hocko <mhocko@suse.com>,
        Jonathan Cameron <Jonathan.Cameron@huawei.com>,
        Jeff Moyer <jmoyer@redhat.com>
Subject: Re: [PATCH v9 1/3] mm/memory_hotplug: replace an open-coded
 kmemdup() in add_memory_resource()
Message-ID: <ZUk2bqoi6YrgMyyO@debian>
References: <20231102-vv-kmem_memmap-v9-0-973d6b3a8f1a@intel.com>
 <20231102-vv-kmem_memmap-v9-1-973d6b3a8f1a@intel.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <20231102-vv-kmem_memmap-v9-1-973d6b3a8f1a@intel.com>
Precedence: bulk

On Thu, Nov 02, 2023 at 12:27:13PM -0600, Vishal Verma wrote:
> A review of the memmap_on_memory modifications to add_memory_resource()
> revealed an instance of an open-coded kmemdup(). Replace it with
> kmemdup().
> 
> Cc: Andrew Morton <akpm@linux-foundation.org>
> Cc: David Hildenbrand <david@redhat.com>
> Cc: Michal Hocko <mhocko@suse.com>
> Cc: Oscar Salvador <osalvador@suse.de>
> Cc: Dan Williams <dan.j.williams@intel.com>
> Reported-by: Dan Williams <dan.j.williams@intel.com>
> Reviewed-by: David Hildenbrand <david@redhat.com>
> Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>
> ---

Reviewed-by: Fan Ni <fan.ni@samsung.com>

>  mm/memory_hotplug.c | 6 +++---
>  1 file changed, 3 insertions(+), 3 deletions(-)
> 
> diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c
> index f8d3e7427e32..6be7de9efa55 100644
> --- a/mm/memory_hotplug.c
> +++ b/mm/memory_hotplug.c
> @@ -1439,11 +1439,11 @@ int __ref add_memory_resource(int nid, struct resource *res, mhp_t mhp_flags)
>  	if (mhp_flags & MHP_MEMMAP_ON_MEMORY) {
>  		if (mhp_supports_memmap_on_memory(size)) {
>  			mhp_altmap.free = memory_block_memmap_on_memory_pages();
> -			params.altmap = kmalloc(sizeof(struct vmem_altmap), GFP_KERNEL);
> +			params.altmap = kmemdup(&mhp_altmap,
> +						sizeof(struct vmem_altmap),
> +						GFP_KERNEL);
>  			if (!params.altmap)
>  				goto error;
> -
> -			memcpy(params.altmap, &mhp_altmap, sizeof(mhp_altmap));
>  		}
>  		/* fallback to not using altmap  */
>  	}
> 
> -- 
> 2.41.0
>