Subject: Re: kern/8628: Garbage can move between virtual terminals?
To: Christian Biere <>
From: David Laight <>
List: netbsd-bugs
Date: 01/25/2004 18:59:08
On Sun, Jan 25, 2004 at 03:00:37AM +0100, Christian Biere wrote:
> The attached patch seems to fix the problem of copying data from one
> VT to another whilst scrolling. It's surely overkill because you only
> need to lock against a VT switch and I'm not sure whether only 
> scrolling can cause characters appearing on the wrong VT.

The other problem is that you lock out interrupts for a long time.
This is especially bad if ISA bus timings apply to the scroll.
(Which was the caes in a commercial Unix...)


David Laight: