linux-kernel - Re: Funky "Blue screen" issue while rebooting from X with 2.6.18-git21

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Date:	Mon, 9 Oct 2006 00:49:50 +0200
From:	"Jesper Juhl" <jesper.juhl@...il.com>
To:	"Pavel Machek" <pavel@....cz>
Cc:	"Adrian Bunk" <bunk@...sta.de>,
	"Linux Kernel Mailing List" <linux-kernel@...r.kernel.org>,
	linux-pm@...l.org
Subject: Re: Funky "Blue screen" issue while rebooting from X with 2.6.18-git21

On 08/10/06, Pavel Machek <pavel@....cz> wrote:
> Hi!
>
> > >> > I have a strange "problem" with 2.6.18-git21 that I've never had with
> > >> > any previous kernel. If I open up an xterm in X, su to root and
> > >> > 'reboot' (or 'shutdown -r now') I instantly get a blue screen that
> > >> > persists until the box actually reboots.
> > >>
> > >> Pavel, is this a known issue or should Jesper bisect?
> > >
> > >Jesper should show it is kernel problem and not userland race.
> > >
> >
> > Jesper will try to do that ;-)
> >
> >
> > >If userspace does kill -15 -1; kill -9 -1, and X fails to shut down in
> > >time, it is userland problem ('should wait for X to shut down').
> > >
> >
> > Well, I just checked my initscript that is run when going into
> > runlevels 0 & 6, and it does this :
> >
> > (...)
> >
> > # Kill all processes.
> > # INIT is supposed to handle this entirely now, but this didn't always
> > # work correctly without this second pass at killing off the processes.
> > # Since INIT already notified the user that processes were being killed,
> > # we'll avoid echoing this info this time around.
> > if [ ! "$1" = "fast" ]; then # shutdown did not already kill all processes
> >  /sbin/killall5 -15
> >  /bin/sleep 5
> >  /sbin/killall5 -9
> > fi
>
> ...so, if X takes more than five seconds to shut down, you kill it
> with -9, resulting in blue screen. Too bad, and not an kernel problem.
>
> Try inserting something like
>
>         while ps -aux | grep myXserver;
>                 sleep 1;
>         done
>
> alternatively, remove/shorten the sleep and you should experience blue
> screen in 2.6.17.
>

I'll try and test these things and report back in a few days when I've
gathered some data.


> > kernels, but since somewhere in the 2.6.18-rc series I've experienced
> > this "blue screen" problem once in a while and I've also had a problem
> > with the screen going all white when switching from X to a plain tty
> > and back (once it goes white it stays that way permanently until I
> > reboot) - I *never* see those issues when running 2.6.17.x and
> > earlier.
>
> Maybe something got slower in 2.6.18?
>                                                                 Pavel
>
Perhaps...

-- 
Jesper Juhl <jesper.juhl@...il.com>
Don't top-post  http://www.catb.org/~esr/jargon/html/T/top-post.html
Plain text mails only, please      http://www.expita.com/nomime.html
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/