Re: [PATCH] PM: acquire device locks prior to suspending

Rafael J. Wysocki
2007-12-14T01:05:59Z

On Friday, 14 of December 2007, Andrew Morton wrote:
> On Fri, 14 Dec 2007 01:08:37 +0100
> "Rafael J. Wysocki" <rjw@sisk.pl> wrote:
>
> > On Thursday, 13 of December 2007, Rafael J. Wysocki wrote:
> > > On Thursday, 13 of December 2007, Andrew Morton wrote:
> > > > On Fri, 21 Sep 2007 15:37:40 -0400 (EDT) Alan Stern <stern@rowland.harvard.edu> 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
> >
> > Ah, that won't work, because git-acpi-build-fix.patch killed
> > /sys/power/pm_test altogether. Sorry.
>
> I was wondering..
>
> What's going on with git-acpi-build-fix.patch anyway? Is there
> something different we should do?

Yes. I've sent a patch to you and Len, here: