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Date:   Mon, 1 Nov 2021 20:38:18 +0000
From:   Matthew Wilcox <willy@infradead.org>
To:     Alexey Makhalov <amakhalov@vmware.com>
Cc:     linux-mm@kvack.org, Andrew Morton <akpm@linux-foundation.org>,
        linux-kernel@vger.kernel.org, stable@vger.kernel.org
Subject: Re: [PATCH] mm: fix panic in __alloc_pages
Message-ID: <YYBQOiuq6WHMjOYf@casper.infradead.org>
References: <20211101201312.11589-1-amakhalov@vmware.com>
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In-Reply-To: <20211101201312.11589-1-amakhalov@vmware.com>
Precedence: bulk

On Mon, Nov 01, 2021 at 01:13:12PM -0700, Alexey Makhalov wrote:
> +++ b/include/linux/gfp.h
> @@ -551,7 +551,8 @@ alloc_pages_bulk_array(gfp_t gfp, unsigned long nr_pages, struct page **page_arr
>  static inline unsigned long
>  alloc_pages_bulk_array_node(gfp_t gfp, int nid, unsigned long nr_pages, struct page **page_array)
>  {
> -	if (nid == NUMA_NO_NODE)
> +	if (nid == NUMA_NO_NODE || (!node_online(nid) &&
> +					!(gfp & __GFP_THISNODE)))
>  		nid = numa_mem_id();
>  
>  	return __alloc_pages_bulk(gfp, nid, NULL, nr_pages, NULL, page_array);

I don't think it's a great idea to push node_online() and the gfp check
into the caller.  Can't we put this check in __alloc_pages_bulk() instead?