Date: Thu, 1 Jun 2017 10:11:13 -0600
From: Jonathan Corbet <corbet@lwn.net>
To: Jia-Ju Bai <baijiaju1990@163.com>
Cc: Larry Finger <Larry.Finger@lwfinger.net>, kvalo@codeaurora.org,
        linux-wireless@vger.kernel.org, b43-dev@lists.infradead.org,
        netdev@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] b43legacy: Fix a sleep-in-atomic bug in
 b43legacy_attr_interfmode_store
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On Thu, 01 Jun 2017 09:05:07 +0800
Jia-Ju Bai <baijiaju1990@163.com> wrote:

> I admit my patches are not well tested, and they may not well fix the bugs.
> I am looking forward to opinions and suggestions :)

May I politely suggest that sending out untested locking changes is a
dangerous thing to do?  You really should not be changing the locking in a
piece of kernel code without understanding very well what the lock is
protecting and being able to say why your changes are safe.  Without that,
the risk of introducing subtle bugs is very high.

It looks like you have written a useful tool that could help us to make
the kernel more robust.  If you are interested in my suggestion, I would
recommend that you post the sleep-in-atomic scenarios that you are
finding, but refrain from "fixing" them in any case where you cannot offer
a strong explanation of why your fix is correct.

Thanks for working to find bugs in the kernel!

jon