Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
Date:   Mon, 7 Jun 2021 14:17:04 +0300
From:   Dan Carpenter <dan.carpenter@oracle.com>
To:     Guenter Roeck <linux@roeck-us.net>
Cc:     Fabio Aiuto <fabioaiuto83@gmail.com>, gregkh@linuxfoundation.org,
        hdegoede@redhat.com, Larry.Finger@lwfinger.net,
        linux-staging@lists.linux.dev, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] staging: rtl8723bs: Use list iterators and helpers
Message-ID: <20210607111704.GT1955@kadam>
References: <20210428173301.149619-1-linux@roeck-us.net>
 <20210604172632.GA1526@agape.jhs>
 <20210605005422.GB255680@roeck-us.net>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <20210605005422.GB255680@roeck-us.net>
User-Agent: Mutt/1.9.4 (2018-02-28)
Precedence: bulk

On Fri, Jun 04, 2021 at 05:54:22PM -0700, Guenter Roeck wrote:
> On Fri, Jun 04, 2021 at 07:26:33PM +0200, Fabio Aiuto wrote:
> > Hello Guenter,
> > 
> > On Wed, Apr 28, 2021 at 10:33:01AM -0700, Guenter Roeck wrote:
> > > The rtl8723bs driver manually re-implements list helper functions
> > > and macros in various ways. Replace with existing list helpers.
> > 
> > I'm testing rtl8723bs on a baytrail tablet (Lenovo Ideapad MIIX 300-10IBY)
> > and applying the tag staging-5.13-rc4, loading r8723bs makes the whole
> > system freezing while trying to connect to local AP.
> > 
> > Only a power off is allowed.
> > 
> > I found that commit b3cd518c5abd42fbc747ef55a5fdc40bf7bf01c0
> > (staging: rtl8723bs: Use list iterators and helpers)
> > introduced the bug.
> > 
> > I'm trying to find out what's wrong with this patch, have you any suggestions?
> 
> Some of the iterators needed the _safe variant which I didn't take into account.
> I thought that was fixed, but maybe some locations were missed.

Ah...  Crud.  As near as I can tell Martin fixed a lot of these in the driver
he is working on, rtl8188eu.  But they still aren't fixed in rtl8723bs.  I looked
at the functions and the following loops need to changed to list_for_each_safe().
(Doing a search for list_del_init() helped during review).

expire_timeout_chk() (both loops)
rtw_acl_remove_sta()
rtw_sta_flush()
stop_ap_mode()

rtw_free_network_queue()
chk_bmc_sleepq_hdl()
rtw_free_all_stainfo()
rtw_free_xmitframe_queue()
dequeue_xmitframes_to_sleeping_queue()
wakeup_sta_to_xmit()  (both loops)
xmit_delivery_enabled_frames()

xmit_xmitframes()
cfg80211_rtw_del_station()

regards,
dan carpenter