Subject: port-i386/2776: dd with 4096K blocksize crashes machine
To: None <>
From: Matthias Scheler <>
List: netbsd-bugs
Date: 09/24/1996 00:26:38
>Number:         2776
>Category:       port-i386
>Synopsis:       dd with 4096K blocksize crashes machine
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    gnats-admin (GNATS administrator)
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Mon Sep 23 15:35:00 1996
>Originator:     Matthias Scheler
Matthias Scheler
>Release:        1.2_BETA
System: NetBSD lyssa 1.2_BETA NetBSD 1.2_BETA (LYSSA) #0: Sat Aug 31 14:20:04 MET DST 1996 tron@lyssa:/usr/src/sys/arch/i386/compile/LYSSA i386

Today I tried to measure the speed of my harddisk with the command
"dd if=/dev/rsd0b of=/dev/null bs=4096k". A few seconds after I
entered the command the system paniced with this message:

panic:	pdti	300d063
Stopped at	_Debugger+0x4:	leave

I tried the same on my Amiga under NetBSD 1.2_BETA but it worked fine.
I retried with "bs=1024k" on the i386 system and it worked, too.

dd if=/dev/rsd0b of=/dev/null bs=4096k

Sorry, I don't know.