arm/180080: Unmapped buffers on ARMv7 big-RAM boards

[Ruslan Bukin]

>Number:         180080
>Category:       arm
>Synopsis:       Unmapped buffers on ARMv7 big-RAM boards
>Confidential:   no
>Severity:       non-critical
>Priority:       low
>Responsible:    freebsd-arm
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Sat Jun 29 04:50:00 UTC 2013
>Closed-Date:
>Last-Modified:
>Originator:     Ruslan Bukin
>Release:        10.0-CURRENT
>Organization:
>Environment:
>Description:
Booting ARMv7 boards with 2GB RAM on board and unmapped_buf_allowed == 1 (default setting) causes panic:

## Starting application at 0x40F00000 ...
KDB: debugger backends: ddb              
KDB: current backend: ddb
Copyright (c) 1992-2013 The FreeBSD Project.
Copyright (c) 1979, 1980, 1983, 1986, 1988, 1989, 1991, 1992, 1993, 1994
	The Regents of the University of California. All rights reserved.
FreeBSD is a registered trademark of The FreeBSD Foundation.
FreeBSD 10.0-CURRENT #19 r252351M: Sat Jun 29 01:20:20 MSK 2013
    root at intel.bsdpad.com:/usr/obj/arm.armv6/usr/home/br/dev/head/sys/ARNDALE arm
FreeBSD clang version 3.3 (tags/RELEASE_33/final 183502) 20130610
WARNING: DIAGNOSTIC option enabled, expect reduced performance.
CPU: Cortex A15 rev 4 (Cortex-A core)
 Supported features: ARM_ISA THUMB2 THUMBEE ARMv4 Security_Ext
 WB disabled EABT branch prediction enabled
LoUU:2 LoC:2 LoUIS:2 
Cache level 1: 
 32KB/64B 2-way data cache WB Read-Alloc Write-Alloc
 32KB/64B 2-way instruction cache Read-Alloc
Cache level 2: 
 1024KB/64B 16-way unified cache WB Read-Alloc Write-Alloc
real memory  = 2147483648 (2048 MB)
panic: kmem_suballoc: bad status return of 3
KDB: enter: panic
[ thread pid 0 tid 0 ]
Stopped at      kdb_enter+0x48: ldrb    r15, [r15, r15, ror r15]!


>How-To-Repeat:

>Fix:


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