Re: [Qemu-devel] [PATCH] Handle suspend in qemu.

[Gleb Natapov]

On Tue, Dec 16, 2008 at 12:46:41AM -0500, Kevin O'Connor wrote:
> On Thu, Dec 11, 2008 at 04:53:32PM +0200, Gleb Natapov wrote:
> > BIOS changes are already upstream.
> > 
> > Reset a PC and tell BIOS that resume from ram is required on the next
> > boot.
> 
> Hi Gleb,
> 
> How can I test this?
> 
> I grabbed the latest bochs from CVS and compiled the BIOS.  I then
> tried it on qemu with Fedora8, Ubuntu-8.04, and winxp images - they
> all seem to say they can suspend, but none actually work when told to.
> 
> The linux images both appear to support standby (cat /sys/power/state
> shows "mem"), but trying suspend (echo -n mem > /sys/power/state)
> returns "Resource temporarily unavailable" and a series of messages in
> /var/log/messages starting with: Freezing of tasks failed after 20.00
> second (1 tasks refusing to freeze)
> 
Never saw that one. What is you qemu command line? Can you try latest
kernel. Searching internet for the "Freezing of tasks failed" suggest
that it may be a kernel bug.

> The winxp image shows "suspend" in the shutdown menu.  However, when I
> click on it I get a dialog that says:
> 
> The device driver for the "Default Monitor" device is preventing the
> machine from entering standby.  Please close all applications and try
> again.  If the problem persists, you may need to update this driver.
> 
This one sound familiar. You need latest vgabios with DPMS support.

--
                        Gleb.