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Date: Tue, 24 Jul 2012 16:46:41 +0300
From: Andrei Emeltchenko <Andrei.Emeltchenko.news@gmail.com>
To: Oliver Neukum <oneukum@suse.de>
Cc: linux-bluetooth@vger.kernel.org
Subject: Re: [RFCv2 02/20] Bluetooth: Process HCI callbacks in a workqueue
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Hi Oliver,

On Tue, Jul 24, 2012 at 03:31:37PM +0200, Oliver Neukum wrote:
> On Tuesday 24 July 2012 16:21:43 Andrei Emeltchenko wrote:
> > +void hci_queue_cb(struct hci_dev *hdev, struct hci_cb_cmd *cmd,
> > +                 struct workqueue_struct *workqueue)
> > +{
> > +       struct hci_cb_work *work;
> > +
> > +       BT_DBG("%s queue cmd %p", hdev->name, cmd);
> > +
> > +       work = kmalloc(sizeof(*work), GFP_KERNEL);
> 
> This looks like prone to deadlocks. You can run networked file
> systems over the link and allocating memory with GFP_KERNEL
> could run into a recursion problem.

Sorry, how this might run into recursion problem?

Best regards 
Andrei Emeltchenko 

> 
> > +       if (!work)
> > +               return;
> > +
> > +       INIT_WORK(&work->work, hci_cb_worker);
> > +       work->hdev = hdev;
> > +       work->cmd = cmd;
> > +       hci_dev_hold(hdev);
> > +
> > +       if (!queue_work(workqueue, &work->work)) {
> > +               kfree(work);
> > +               hci_dev_put(hdev);
> > +       }
> > +}
> 
> 	Regards
> 		Oliver
>