From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx153.postini.com [74.125.245.153]) by kanga.kvack.org (Postfix) with SMTP id 04B836B006C for ; Wed, 31 Oct 2012 11:20:03 -0400 (EDT) Date: Wed, 31 Oct 2012 11:20:02 -0400 (EDT) From: Alan Stern Subject: Re: [PATCH v3 2/6] PM / Runtime: introduce pm_runtime_set[get]_memalloc_noio() In-Reply-To: Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-linux-mm@kvack.org List-ID: To: Ming Lei Cc: Oliver Neukum , linux-kernel@vger.kernel.org, Minchan Kim , Greg Kroah-Hartman , "Rafael J. Wysocki" , Jens Axboe , "David S. Miller" , Andrew Morton , netdev@vger.kernel.org, linux-usb@vger.kernel.org, linux-pm@vger.kernel.org, linux-mm@kvack.org On Wed, 31 Oct 2012, Ming Lei wrote: > The below idea may help the problem which 'memalloc_noio' flag isn't set during > usb_reset_device(). > > - for usb mass storage device, call pm_runtime_set_memalloc_noio(true) > inside usb_stor_probe2() and uas_probe(), and call > pm_runtime_set_memalloc_noio(false) inside uas_disconnect() > and usb_stor_disconnect(). Why would you want to do that? The probe and disconnect routines usually -- but not always -- run in the khubd thread. Surely you don't want to prevent khubd from using GFP_KERNEL? And what if probe runs in khubd but disconnect runs in a different thread? Alan Stern -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org