amd64/158552: ROOT MOUNT ERROR (caused by AHCI module)

[Derek Schaeffer]

>Number:         158552
>Category:       amd64
>Synopsis:       ROOT MOUNT ERROR (caused by AHCI module)
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    freebsd-amd64
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Fri Jul 01 06:20:00 UTC 2011
>Closed-Date:
>Last-Modified:
>Originator:     Derek Schaeffer
>Release:        8.2-RC1
>Organization:
University Of Louisville
>Environment:
[X at pcbsd-8686 /usr/home/X]$ uname -a
FreeBSD pcbsd-8686 8.2-RC1 FreeBSD 8.2-RC1 #4: Mon Dec 27 12:25:57 PST 2010     root at build8x64.pcbsd.org:/usr/obj/usr/pcbsd-build82/fbsd-source/8.2/sys/PCBSD  amd64

>Description:
FreeBSD gives "ROOT MOUNT ERROR" when the kernel is loading modules at startup.  This is regardless if the installation has been dual-booted or not.  The problem appears to be the AHCI module.

Hardware:
Intel i7 980x processor
MSI Big Bang-XPower motherboard
XFX HD-485X-ZNFC Radeon HD 4850 video card
DDR3 2000 ram (16GB)
>How-To-Repeat:
FreeBSD does not have AHCI enabled by default, however, PCBSD does.  

In the loader.conf file,
 ahci_load="YES"
will cause the problem to occur. 
>Fix:
In the loader.conf file,
 ahci_load="NO"
allows normal startup.  

The problem was addressed in the thread: http://forums.freebsd.org/showthread.php?t=20724

>Release-Note:
>Audit-Trail:
>Unformatted: