On Mon, Jun 07, 2021 at 02:17:04PM +0300, Dan Carpenter wrote:

On Fri, Jun 04, 2021 at 05:54:22PM -0700, Guenter Roeck wrote:

quoted

On Fri, Jun 04, 2021 at 07:26:33PM +0200, Fabio Aiuto wrote:

quoted

Hello Guenter,

On Wed, Apr 28, 2021 at 10:33:01AM -0700, Guenter Roeck wrote:

quoted

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).

Hans wants the patch introducing the problem reverted, so I won't bother
sending a fix. Sorry for the trouble. Learned a lesson (I hope).

Guenter

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