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From: John Baldwin <jhb@freebsd.org>
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Date: Thu, 27 Jul 2006 17:35:54 -0400
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Cc: Dag-Erling =?iso-8859-1?q?Sm=F8rgrav?= <des@des.no>, Intron <mag@intron.ac>,
	Hans Petter Selasky <hselasky@c2i.net>
Subject: Re: How to Use ddb(4)?
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On Thursday 27 July 2006 15:04, Hans Petter Selasky wrote:
> On Thursday 27 July 2006 20:40, Dag-Erling Sm=F8rgrav wrote:
> > maksim yevmenkin <maksim.yevmenkin@savvis.net> writes:
> > > Dag-Erling Sm=F8rgrav <des@des.no> writes:
> > > > No, kbdmux needs to be fixed so it works in DDB.
> > >
> > > actually, atkbd(4) needs to be fixed to support "polled" mode :)
> >
> > It used to work fine before kbdmux(4) came along...
> >
>=20
> Just a comment: Don't forget to lock Giant before calling anything in the=
=20
> keyboard layer. That means DDB must lock Giant, else at least my new USB=
=20
> keyboard driver will panic, saying Giant is not owned. The old USB keyboa=
rd=20
> driver did not care about this.

DDB should not be acquiring locks or depend on being able to do so.  When y=
ou=20
panic the machine is an unknown state for one, and you really want to leave=
=20
the overall system state as undisturbed as possible while in the debugger t=
o=20
aid in debugging.

=2D-=20
John Baldwin