linux-kernel - Re: [regression] 2.6.30 leaking keys on console switch

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]

Message-ID: <20091023202906.GD27185@elf.ucw.cz>
Date:	Fri, 23 Oct 2009 22:29:07 +0200
From:	Pavel Machek <pavel@....cz>
To:	Dmitry Torokhov <dmitry.torokhov@...il.com>
Cc:	Andi Kleen <andi@...stfloor.org>, Jiri Kosina <jkosina@...e.cz>,
	rjw@...k.pl, linux-input@...r.kernel.org,
	linux-kernel@...r.kernel.org
Subject: Re: [regression] 2.6.30 leaking keys on console switch

On Wed 2009-10-21 01:15:30, Dmitry Torokhov wrote:
> On Mon, Oct 19, 2009 at 11:38:36PM +0200, Pavel Machek wrote:
> > On Wed 2009-10-14 00:39:28, Dmitry Torokhov wrote:
> > > On Wed, Oct 14, 2009 at 09:19:50AM +0200, Andi Kleen wrote:
> > > > > Btw, what kind of keyboard is this? I was playing today but I could not
> > > > > get my USB keyboards to report release of more than 1 key per report....
> > > > 
> > > > The log was with a PS/2<->USB adapter, with a PS/2 keyboard connected
> > > > to a USB port through it.
> > > > 
> > > 
> > > Hmm, I don't think I have one of those... It is curious beast - we have
> > > software autorepeat for HID but PS/2 keyboards do autorepeat
> > > themselves... What will combination do?
> > 
> > I always wondered how that's supposed to work... on loaded system. As
> > linux is not realtime system, it can't, afaict.
> 
> What exactly requires realtime? Surely not autorepeat...

Well, ps/2 does not provide timestamps, neither does USB AFAICT. So if
you hit say interrupt latency, you'll repeat keys one too many times
or something.

[But if X does autorepeat in software, that's even worse. That means
that scheduling latency can cause autorepeat glitches, and that's
probably what I'm seeing here. And I haaaaaaaaaaaaaaate when my
tyyyyyyping goes like this just because I have background load.]

									Pavel
-- 
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.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/