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Date:   Wed, 30 Dec 2020 20:59:44 +0800
From:   Hui Su <sh_def@163.com>
To:     Matthew Wilcox <willy@infradead.org>
Cc:     Andrew Morton <akpm@linux-foundation.org>, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org, Michal Hocko <mhocko@suse.com>
Subject: Re: [PATCH] mm/page_alloc: remove the static for local variable
 node_order
Message-ID: <20201230125944.GA2040977@ubuntu-A520I-AC>
References: <20201230114014.GA1934427@ubuntu-A520I-AC>
 <20201230124233.GE28221@casper.infradead.org>
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Hi, Matthew:

On Wed, Dec 30, 2020 at 12:42:33PM +0000, Matthew Wilcox wrote:
> On Wed, Dec 30, 2020 at 07:40:14PM +0800, Hui Su wrote:
> > local variable node_order do not need the static here.
> 
> It bloody well does.  It can be up to 2^10 entries on x86 (and larger
> on others) That's 4kB which you've now moved onto the stack.
> 
Thanks for your explanation, this change will put too much onto the stack
in some cases which i didn't consider.

Please ignore this change.

> Please, learn more about what you're doing.  I suggest sending patches
> to drivers/staging; that will help you learn how to submit patches to
> linux.