Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965200Ab2EWP1Y (ORCPT ); Wed, 23 May 2012 11:27:24 -0400 Received: from iolanthe.rowland.org ([192.131.102.54]:51800 "HELO iolanthe.rowland.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S933684Ab2EWP1V (ORCPT ); Wed, 23 May 2012 11:27:21 -0400 Date: Wed, 23 May 2012 11:27:19 -0400 (EDT) From: Alan Stern X-X-Sender: stern@iolanthe.rowland.org To: Lin Ming cc: Jens Axboe , , , Subject: Re: [RFC PATCH v3 0/4]: block layer runtime pm In-Reply-To: Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=UTF-8 Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 997 Lines: 26 On Wed, 23 May 2012, Lin Ming wrote: > On Wed, May 23, 2012 at 11:03 PM, Alan Stern wrote: > > On Wed, 23 May 2012, Lin Ming wrote: > > > >> Another thing need to check is if system suspend/resume works. > > > > Right! ?Although I would hope that your work doesn't interfere at all > > with system sleep, since it touches only the runtime PM pathways. > > sd_sync_cache and sd_start_stop_device are changed with REQ_PM set. > And they are called for system suspend too. > > So it probably will have problem. People have already run into problems where system suspend occurred at a time when a SCSI device was already runtime suspended. That's why scsi_bus_suspend_common() includes an appropriate check. Alan Stern -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/