Subject: Re: "Bad address" reading files
To: Dave Huang <>
From: Chuck Silvers <>
List: current-users
Date: 02/26/2001 21:55:54
in post-UBC -current there's a problem where many filesystem errors
are reported as EFAULT instead of whatever the real error is.
I know what needs to be done to fix it, but I've been fixing
worse problems so I haven't had a chance to deal with this yet.
I'll hopefully get to this in a few weeks.


On Sun, Feb 25, 2001 at 07:10:34PM -0600, Dave Huang wrote:
> On Sun, 25 Feb 2001, Jaromír Dolecek wrote:
> > This is one of remaining issues with UBC on -current IIRC.
> > It's definitely a known bug.
> Oh, okay :) Not a big problem... a mostly unrelated question though: The
> file is an image of a friend's hard drive that Windows (or something)
> managed to corrupt. I fixed up the BPB in the boot sector, vnconfiged
> it, and mounted the partition (it's a FAT32 partition), then copied what
> I could off of it. Most of the files copied fine, but a few give me a
> "Bad address" error. For example:
> yerfable /tmp# ktrace cat /mnt/SLSLO
> cat: /mnt/SLSLO: Bad address
> yerfable /tmp# kdump
> [ stuff deleted ]
>  14609 cat      CALL  read(0x3,0x120118000,0x10000)
>  14609 cat      RET   read -1 errno 14 Bad address
> I'm guessing the FAT entry for that file is corrupt? Or is this possibly
> related to the UBC bug? ("Bad address" does seem like an unusual error
> for a filesystem to give... but then, it is a vnd rather than an actual
> disk).