From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Rafael J. Wysocki" Subject: Re: [PATCH] PM: acquire device locks prior to suspending Date: Thu, 13 Dec 2007 17:58:37 +0100 Message-ID: <200712131758.38116.rjw@sisk.pl> References: <20071212234201.a8932915.akpm@linux-foundation.org> Mime-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20071212234201.a8932915.akpm@linux-foundation.org> Content-Disposition: inline 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: Andrew Morton Cc: linux-pm@lists.linux-foundation.org List-Id: linux-pm@vger.kernel.org On Thursday, 13 of December 2007, Andrew Morton wrote: > On Fri, 21 Sep 2007 15:37:40 -0400 (EDT) Alan Stern wrote: > > > This patch (as994) reorganizes the way suspend and resume > > notifications are sent to drivers. The major changes are that now the > > PM core acquires every device semaphore before calling the methods, > > and calls to device_add() during suspends will fail. > > Causes my t61p to deadlock during suspend-to-RAM. Really late - the little > moon symbol has started to flash but the LCD is still powered and the > cursor still blinks. Only a poweroff restores control. Most probably, one of the drivers or a CPU hotplug notifier unregisters a device during suspend (wrong). Please boot with no_console_suspend and check if the box survives (with this patch applied): # echo 8 > /proc/sys/kernel/printk # echo processors > /sys/power/pm_test # echo mem > /sys/power/state If it doesn't, you can try # echo platform > /sys/power/pm_test # echo mem > /sys/power/state and # echo devices > /sys/power/pm_test # echo mem > /sys/power/state