It took me a while to track this down, with a few false paths.
I have verified this is kernel side, so..
The basic problem goes like this, start X, switch away from X with
ctrl-alt-Fn, then switch back to X, this is where the fun starts.
Sometimes (this seems to be a race condition, but I have no idea what it
depends on) things go, interestingly wrong, X gets the message that it
has the VC, it takes control of the screen, and the kernel grabs the
ctrl-alt-Fn used to switch away from X, and does not tell X that it no
longer actually HAS the console.
Resulting in keyboard input going to the VC you switched out from X to,
and the kernel believing that it can print to the screen, but with X also
still trying to control the screen.
If you switch back to the VC X is on then things work from there,
however this is quite obviously quite broken.
Verification that this was kernel side was not too hard, removing the
console binds for ctrl-alt-Fn makes the problem go away.
This happens for 2.5.x, but not 2.4.20, I don't know where in 2.5.x it
started.
Thanks.
Zephaniah E. Hull.
--
1024D/E65A7801 Zephaniah E. Hull <[email protected]>
92ED 94E4 B1E6 3624 226D 5727 4453 008B E65A 7801
CCs of replies from mailing lists are requested.
[1] Yes, we ARE rather dull people. We appreciate being dull people.
Exciting is only good when it happens to someone else ... as in "an
exciting wreck", "an exciting plane crash", "an exciting install of
Windows XP", et al.
-- Ralph Wade Phillips in the Scary Devil Monastery.
On Mon, Dec 23, 2002 at 04:38:37PM +0100, Rudmer van Dijk wrote:
> Hi,
>
> I have also been seeing this kind of behavior, but more with deadlocks than
> messed up in/output. Only I have not had the time to see where the problem
> lies...
>
> my problems are appearing when I switch away from X:
> 1) black screen, completely dead (not responding to keyboard or network)
> 2) normal console but after some time, dead (as in 1)
> 3) mostly black screen with some colored vertical lines and a mouse pointer,
> not responsive to keyboard but system can be reached over the network
>
> and the funny thing is that it does not always happen, sometimes I am able to
> switch between X and console for 10 times or more...
To cheat, just tap the Fn key twice when switching to X, to cheat better
change your keymap to not have binds for ctrl-alt-Fn.
It seems very likely that while some cards can survive being poked at by
the vgacon driver while the X driver is also talking to them, other
cards have more, significant problems.
>
> I have been seeing this since 2.5.50.
But it did not at 2.5.49? That should definitely help him isolate it..
Zephaniah E. Hull.
(All I want for Christmas is a /job/.)
>
> Rudmer
--
1024D/E65A7801 Zephaniah E. Hull <[email protected]>
92ED 94E4 B1E6 3624 226D 5727 4453 008B E65A 7801
CCs of replies from mailing lists are requested.
}>No. I just point out to troublemakers that I have an English degree,
}>which means that I am allowed to make changes to the English language.
}>(What _else_ could it possibly be for?)
}Wow; in that case, my physics degree is *WAY* more useful than I
}had thought.
This just proves how useless a computer science degree is: there is hardly
any useful science involved at all. I want my computer black magic degree!
-- Victoria Swann, Jonathan Dursi, and D. Joseph Creighton on ASR
Hi!
> To cheat, just tap the Fn key twice when switching to X, to cheat better
> change your keymap to not have binds for ctrl-alt-Fn.
>
> It seems very likely that while some cards can survive being poked at by
> the vgacon driver while the X driver is also talking to them, other
> cards have more, significant problems.
> >
> > I have been seeing this since 2.5.50.
>
> But it did not at 2.5.49? That should definitely help him isolate it..
I believe Ive seen the "both kernel and X write
to the screen" back in 2.2.X days on sparc machines.
--
Pavel
Written on sharp zaurus, because my Velo1 broke. If you have Velo you don't need...