From mboxrd@z Thu Jan 1 00:00:00 1970 From: Petr Vorel Subject: Re: [PATCH 1/1] r8152: fix NULL pointer dereference in r8152_poll Date: Mon, 13 Mar 2017 16:37:46 +0100 Message-ID: <20170313153745.wu7cf254obh2x2gn@dell5510> References: <20170313124727.4681-1-petr.vorel@gmail.com> <1489411084.28631.78.camel@edumazet-glaptop3.roam.corp.google.com> <1489411184.28631.80.camel@edumazet-glaptop3.roam.corp.google.com> Reply-To: Petr Vorel Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: netdev@vger.kernel.org, hayeswang@realtek.com, davem@davemloft.net To: Eric Dumazet Return-path: Received: from mail-wm0-f67.google.com ([74.125.82.67]:36420 "EHLO mail-wm0-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751188AbdCMPht (ORCPT ); Mon, 13 Mar 2017 11:37:49 -0400 Received: by mail-wm0-f67.google.com with SMTP id v190so10498164wme.3 for ; Mon, 13 Mar 2017 08:37:48 -0700 (PDT) Content-Disposition: inline In-Reply-To: <1489411184.28631.80.camel@edumazet-glaptop3.roam.corp.google.com> Sender: netdev-owner@vger.kernel.org List-ID: Hi Eric, > > The proper work around is to enclose the napi_schedule() in a > > local_bh_enable()/local_bh_disable() pair. > Something like : > --- a/drivers/net/usb/r8152.c > +++ b/drivers/net/usb/r8152.c > @@ -3703,8 +3703,10 @@ static int rtl8152_resume(struct usb_interface *intf) > napi_enable(&tp->napi); > clear_bit(SELECTIVE_SUSPEND, &tp->flags); > smp_mb__after_atomic(); > + local_bh_disable(); > if (!list_empty(&tp->rx_done)) > napi_schedule(&tp->napi); > + local_bh_enable(); Unfortunately this doesn't work. Code in r8152.c doesn't use local_bh_enable()/local_bh_disable(). I tried to lock it with spin_lock_bh()/spin_unlock_bh() and with mutex_lock()/mutex_unlock() but neither work. Kind regards, Petr