From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jeremy Maitin-Shepard Subject: Re: Re: Hibernation considerations Date: Fri, 20 Jul 2007 18:48:24 -0400 Message-ID: <87zm1qofnr.fsf@jbms.ath.cx> References: Mime-Version: 1.0 Content-Type: text/plain Return-path: In-Reply-To: (Alan Stern's message of "Fri\, 20 Jul 2007 18\:35\:16 -0400 \(EDT\)") List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: linux-pm-bounces@lists.linux-foundation.org Errors-To: linux-pm-bounces@lists.linux-foundation.org To: Alan Stern Cc: david@lang.hm, LKML , Milton Miller , Ying Huang , linux-pm List-Id: linux-pm@vger.kernel.org Alan Stern writes: > On Fri, 20 Jul 2007, Jeremy Maitin-Shepard wrote: >> >> when doing a suspend-to-ram you get to a point where you just don't use >> >> any userspace. >> >> > What do you mean? How can you prevent user tasks from running? That's >> > basically what the freezer does, and the whole point of this approach >> > is to eliminate the freezer. Right? >> >> Presumably no tasks at all would be scheduled. > How would you prevent tasks from being scheduled? How would you > prevent drivers from deadlocking because in order to put their device > in a low-power state they need to acquire a lock which is held by a > user task? Perhaps this isn't an issue once the device is already quiesced. I'm just conjecturing. [snip] -- Jeremy Maitin-Shepard