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Date: Thu, 15 Jun 2017 12:16:57 +0100
From: Al Viro <viro@ZenIV.linux.org.uk>
To: Daeho Jeong <daeho.jeong@samsung.com>
Cc: edumazet@google.com, mguzik@redhat.com,
        linux-fsdevel@vger.kernel.org
Subject: Re: [PATCH] fs: initialize resize_wait wait queue of init task
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On Wed, Jun 14, 2017 at 09:27:21AM +0900, Daeho Jeong wrote:
> We don't initialize resize_wait of init task now and all the kernel
> threads share this uninitialized resize_wait wait queue because they
> are sharing the file table of init task. Therefore, when expanding
> this file table shared by the kernel threads, we encounter kernel panic
> by accessing the NULL resize_wait wait queue.

*shrug*

Not a problem, but kernel threads playing with init_files are seriously
asking for trouble.  It *is* shared and uncooperating threads playing
with shared descriptor table can fuck up very easily.  I can apply that,
but it might make more sense to restrict the use of that thing...