Remounting a drive as read/write crashes the system and no dmesg.boot

[Mel Flynn]

On Friday 21 August 2009 07:34:11 Scott Schappell wrote:
> Looking at info.0 I see:
>
>
> Dump header from device /dev/ad0s1b
>    Architecture: i386
>    Architecture Version: 2
>    Dump Length: 155131904B (147 MB)
>    Blocksize: 512
>    Dumptime: Fri Aug 21 08:27:45 2009
>    Hostname: arthur.silvertree.org
>    Magic: FreeBSD Kernel Dump
>    Version String: FreeBSD 7.2-RELEASE-p3 #1: Fri Aug 14 13:27:47 PDT
> 2009
>      root at arthur.silvertree.org:/usr/obj/usr/src/sys/ARTHUR
>    Panic String: ffs_sync: rofs mod
>    Dump Parity: 2778312054
>    Bounds: 0
>    Dump Status: good
>
> This is interesting:
>
> "Panic String: ffs_sync: rofs mod"
>
> It looks I'm guessing this is saying "read only file system
> modified".  So it looks like the problem is with mount?
>
> If there's anything you want me to pull from the vmcore.0 let me know.
>
> Again, this happens with the drive mounted RO from fstab. Unmounted
> then mount -o rw /backup.
>
> Something is amiss, and first blush doesn't seem to be hardware related.

There should be a backtrace in info.0 already. That part contains more 
relevant information.
-- 
Mel