From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Rafael J. Wysocki" Subject: Re: Question about hibernation Date: Wed, 6 Oct 2010 00:43:30 +0200 Message-ID: <201010060043.30489.rjw@sisk.pl> References: Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: 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: linux-pm@lists.linux-foundation.org List-Id: linux-pm@vger.kernel.org On Tuesday, October 05, 2010, Raj Kumar wrote: > > Hi Alan, > > I have question regarding the hibernation mode in linux. > > 1) In normal suspend to ram, is freezing of tasks necessary while suspend to ram in current linux power management core? Yes, it is. > 2) In hibernation mode, is freezing of tasks done before normal suspend/resumes in order to that hibernation image is in sync? That depends on what you mean by normal "suspend/resumes". Generally speaking, the hibernate code freezes tasks before preallocating image memory. > My issue is because it might be possible that there is some part of device driver which is user space and another part is kernel space > then in suspend to ram and hibernation mode is freezing of all user space part is done before kernel side or it differs while > suspend to ram and hibernation mode? User space is always frozen before suspend and hibernation. Thanks, Rafael