From owner-freebsd-hackers Thu Jul 20 13:06:09 1995 Return-Path: hackers-owner Received: (from majordom@localhost) by freefall.cdrom.com (8.6.11/8.6.6) id NAA21005 for hackers-outgoing; Thu, 20 Jul 1995 13:06:09 -0700 Received: from godzilla.zeta.org.au (godzilla.zeta.org.au [203.2.228.34]) by freefall.cdrom.com (8.6.11/8.6.6) with ESMTP id NAA20999 for ; Thu, 20 Jul 1995 13:06:02 -0700 Received: (from bde@localhost) by godzilla.zeta.org.au (8.6.9/8.6.9) id GAA06089; Fri, 21 Jul 1995 06:01:23 +1000 Date: Fri, 21 Jul 1995 06:01:23 +1000 From: Bruce Evans Message-Id: <199507202001.GAA06089@godzilla.zeta.org.au> To: hm@ernie.altona.hamburg.com, terry@cs.weber.edu Subject: Re: FreeBSD 2.0.5 system hangs Cc: freebsd-hackers@freebsd.org Sender: hackers-owner@freebsd.org Precedence: bulk >> > 1) in an xterm, while scrolling, the system sometimes and totally >> > unreproducable just hangs. This seems to occur more often the smaller >> ... >> Move sio3 off of irq 7. >> >> IRQ 7 is the garbage interrupt for untrapped interrupts. >I wasn't aware of this ! Perhaps because it isn't true. IRQ 7 is the interrupt for garbage trapped interrupts. Using it for sio shouldn't cause a hang. Sio will ignore any extra interrupts and recover from others. OTOH if the interrupt was for a driver that doesn't recover from lost interrupts, then that driver may hang. It is best to leave IRQ7 disconnected so that its default interrupt handler can warn about the missed interrupt. The warning is usually lost in other ways - by using the interrupt for a printer, or by warnings being turned off after 5. Some systems used to generate streams of warnings. Bruce