RE: [PATCH] wifi: rtw88: schedule rx work after everything is set up

From: Ping-Ke Shih
Date: Mon May 27 2024 - 23:00:43 EST


+ Tim K (reporter)

Hi Tim,

Could you please try this patch can help your rtw8822bu?

Ping-Ke Shih <pkshih@xxxxxxxxxxx> wrote:
> Kalle Valo <kvalo@xxxxxxxxxx> wrote:
> > marcin.slusarz@xxxxxxxxx writes:
> >
> > > From: Marcin Ślusarz <mslusarz@xxxxxxxxx>
> > >
> > > Right now it's possible to hit NULL pointer dereference in
> > > rtw_rx_fill_rx_status on hw object and/or its fields because
> > > initialization routine can start getting USB replies before
> > > rtw_dev is fully setup.
> > >
> > > The stack trace looks like this:
> > >
> > > rtw_rx_fill_rx_status
> > > rtw8821c_query_rx_desc
> > > rtw_usb_rx_handler
> > > ...
> > > queue_work
> > > rtw_usb_read_port_complete
> > > ...
> > > usb_submit_urb
> > > rtw_usb_rx_resubmit
> > > rtw_usb_init_rx
> > > rtw_usb_probe
> > >
> > > So while we do the async stuff rtw_usb_probe continues and calls
> > > rtw_register_hw, which does all kinds of initialization (e.g.
> > > via ieee80211_register_hw) that rtw_rx_fill_rx_status relies on.
> > >
> > > Fix this by moving the first usb_submit_urb after everything
> > > is set up.
> > >
> > > For me, this bug manifested as:
> > > [ 8.893177] rtw_8821cu 1-1:1.2: band wrong, packet dropped
> > > [ 8.910904] rtw_8821cu 1-1:1.2: hw->conf.chandef.chan NULL in rtw_rx_fill_rx_status
> > > because I'm using Larry's backport of rtw88 driver with the NULL
> > > checks in rtw_rx_fill_rx_status.
> > >
> > > This should fix:
> > > https://marc.info/?l=linux-wireless&m=167907688311943&w=2
> >
> > Please use permalinks from lore.kernel.org, marc links don't contain the
> > Message-Id and are hence unreliable.
> >
>
> Use tags below:
>
> Reported-by: Tim K <tpkuester@xxxxxxxxx>
> Closes:
> https://lore.kernel.org/linux-wireless/CA+shoWQ7P49jhQasofDcTdQhiuarPTjYEDa--NiVVx494WcuQw@mail.gmail.
> com/
>