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Date: Fri, 15 Jan 2016 14:07:22 +0900
From: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>
To: Minchan Kim <minchan@kernel.org>
Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>,
        Junil Lee <junil0814.lee@lge.com>,
        Andrew Morton <akpm@linux-foundation.org>, ngupta@vflare.org,
        linux-mm@kvack.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] zsmalloc: fix migrate_zspage-zs_free race condition
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On (01/15/16 13:49), Minchan Kim wrote:
[..]
> > 
> > or zs_free() can take spin_lock(&class->lock) earlier, it cannot free the
> 
> Earlier? What do you mean? For getting right class, we should get a stable
> handle so we couldn't get class lock first than handle lock.
> If I misunderstand, please elaborate a bit.

ohh... you're right. I didn't really check the code when I was writing
this. please forget what I said.


yeah, agree, record_obj() better be doing this.

	-ss