Subject: Re: [PATCH 1/2 v5] usbnet: allow status interrupt URB to always be active

From: Oliver Neukum <[email-masked]>
Date: Thu, 11 Apr 2013 11:53:16 +0200

On Thursday 11 April 2013 16:09:16 Ming Lei wrote:
> On Thu, Apr 11, 2013 at 2:50 PM, Oliver Neukum <[email-masked]> wrote:
> > On Thursday 11 April 2013 10:31:31 Ming Lei wrote:
> >
> >> 'mem_flags' isn't needed any more since we can apply allocation
> >> of GFP_NOIO automatically in resume path now, and you can always
> >> use GFP_KERNEL safely. Considered that it is a API, please don't
> >> introduce it.
> >
> > The automatic system goes a long way, but there are corner cases, for example
> > work queues, which still need mem_flags.
> 
> Could you explain why work queue need GFP_NOIO?

Your fix for the memory allocation depends on it happening in the same
context. If you execute code on a work queue this happens in the context
of a kernel thread.

> and the use case for
> usbnet?

Processing your response from a work queue.

	Regards
		Oliver