Re: Two problems with system sleep

["Rafael J. Wysocki" <rjw@sisk.pl>]

On Friday 12 February 2010, Alan Stern wrote:
> Rafael:
> 
> My newly-installed desktop system is experiencing a couple of problems 
> with system sleep.  (Oddly enough, the old one was working fairly 
> well...)
> 
> The first has to do with the serial port.  It doesn't appear to resume 
> correctly.  I booted with:
> 
> 	console=ttyS0,115200 console=tty0 earlyprintk=serial,ttyS0,115200
> 		no_console_suspend
> 
> Then I did "echo processors >pm_test ; echo mem >state".  In spite of
> the no_console_suspend, data stopped going out through the serial port
> after the following appeared:
> 
> [  273.664785] PM: Preparing system for mem sleep
> [  273.677133] Freezing user space processes ... (elapsed 0.01 seconds) done.
> [  273.698837] Freezing remaining freezable tasks ... (elapsed 0.01 seconds) done.
> [  273.718799] PM: Entering mem sleep
> [  273.794463] serial 00:05: disabled
> 
> even though things continued to appear on the VT screen.  The only
> other text to show up on the serial monitor was this line:
> 
> [  279.069204] serial 00:05: activated
> 
> The normal sequence of messages showed up on the screen, but everything
> was oddly slow.  Check out some sample timestamps:
> 
> [  332.120130] ehci_hcd 0000:00:1d.7: GetStatus port 8 status 001005 POWER sig=se0 PE CONNECT
> [  334.592054] usb 2-8: finish resume
> [  335.613747] PM: resume of devices complete after 56629.644 msecs
> [  337.426230] PM: Finishing wakeup.
> [  338.430797] Restarting tasks ... 
> [  339.378108] usb 2-8: usb auto-suspend
> [  340.554760] hub 1-0:1.0: state 7 ports 2 chg 0000 evt 0000
> [  342.204128] done.
> [  342.816603] hub 2-0:1.0: state 7 ports 8 chg 0000 evt 0000
> 
> The delay between each line and its successor is proportional to the
> line's length, as though the kernel were still trying to send the 
> characters out through the serial port but at 360 baud!  Is anybody in 
> charge of the 8250 driver these days?

Quite frankly I'm not sure.  Greg, do you know?

> The bigger problem is that with a normal sleep ("echo none >pm_test"),
> the system doesn't wake up.  Pressing a key or a mouse button does
> nothing.  Pressing the power button causes the machine to start up
> again, but the screen remains blank and there's no response to network
> pings.
> 
> This was with more or less standard 2.6.33-rc6 (Greg KH's patch set was 
> applied but none of your PM patches).  The motherboard is an Intel 
> ICH5 with a 32-bit CPU.  Any ideas on ways to approach this?

That depends on the graphics adapter.  Is it Intel or AMD?

Rafael