On Wed, Jan 04, 2017 at 11:03:32AM +0800, Jason Wang wrote:
> On 2017年01月03日 21:33, Stefan Hajnoczi wrote:
> > On Wed, Dec 28, 2016 at 04:09:31PM +0800, Jason Wang wrote:
> > > +static int tun_rx_batched(struct tun_file *tfile, struct sk_buff *skb,
> > > +			  int more)
> > > +{
> > > +	struct sk_buff_head *queue = &tfile->sk.sk_write_queue;
> > > +	struct sk_buff_head process_queue;
> > > +	int qlen;
> > > +	bool rcv = false;
> > > +
> > > +	spin_lock(&queue->lock);
> > Should this be spin_lock_bh()?  Below and in tun_get_user() there are
> > explicit local_bh_disable() calls so I guess BHs can interrupt us here
> > and this would deadlock.
> 
> sk_write_queue were accessed only in this function which runs under process
> context, so no need for spin_lock_bh() here.

I see, thanks!

Stefan