[SeaBIOS] S3 resume is broken on QEMU

[Peter Stuge]

Gleb Natapov wrote:
> > In real life, SeaBIOS does not need to run the VGA BIOS when I resume
> > my ThinkPad with coreboot.
> 
> So do not run it on a ThinkPad.

If it's not needed on my machine, why would it be the right solution
anywhere else?


> BTW are you resuming to X? Can you switch to a console and
> suspend/resume there to see if it works?

Both work fine. The KMS driver restores the hardware correctly.


> > Why should QEMU impose an artificial requirement which additionally
> > aligns poorly with the common specifications?
> 
> There is nothing artificial about the requirement. It exists on real HW.
> Here for instance: http://www.nvnews.net/vbulletin/showthread.php?t=130909

It *is* rtificial because it is obviously not always neccessary.

In the above forum post it's also clear that the problem is that the
graphics driver is unable to resume properly. During the three years
since that post maybe the NVIDIA driver situation has improved. (I
haven't used NVIDIA graphics in a while, so I can't say there.)


> > > There is not way OSMP can restore unknown state of a random vga card
> > > without special driver for that card.
> > 
> > It sounds like QEMU just needs a simple KMS driver. Isn't there
> > actually one already, which might fit well?
> 
> QEMU has no drivers. It has devices.

Yeah. You mentioned "driver" so I did the same. Sorry for not making
it more explicit that like you I also refered to a driver in the
operating system.


> > That model completely and utterly fails with every operating system
> > today, where indeed there are, must be and should be, device drivers.
> 
> And meanwhile, in real life, you cannot resume Linux into console.

It works fine for me. Try it on your machine with a KMS driver.
They've been around for a few years now, and as I mentioned I believe
there is a KMS driver intended for guest use too.


> This abstract graphics HW surely helped Linux adoption. Without it you
> wouldn't be able to run Linux even in a text mode on most HW in late
> 90s since nobody published HW spec and wrote drivers for Linux.

20 years later the software and hardware landscape is very different.


//Peter