Donald Poole, Jr.

"Unhandled fault: Alignment Exception" Error booting Freescale 2.6.35 Kernel

Discussion created by Donald Poole, Jr. on Nov 30, 2011
Latest reply on Aug 17, 2012 by Michael McTernan

Hello All,

 

I've downloaded and compiled Freescale's 2.6.35 kernel from their opensource gitweb, but when I boot the kernel on my i.MX53QSB I get a series of 8 Unhandled fault: alignment exception errors.  I've attached my complete boot output, but the first occurrence of the boot error is shown below:

MMC read: dev # 0, block # 2048, count 6144 ... 6144 blocks read: OK
## Booting kernel from Legacy Image at 70800000 ...
   Image Name:   Linux-2.6.35.3
   Image Type:   ARM Linux Kernel Image (uncompressed)
   Data Size:    2917388 Bytes = 2.8 MiB
   Load Address: 70008000
   Entry Point:  70008000
   Verifying Checksum ... OK
   Loading Kernel Image ... OK
OK

Starting kernel ...

Linux version 2.6.35.3 (victory@ubuntu) (gcc version 4.5.2 (Sourcery G++ Lite 2011.03-41) ) #1 PREEMPT Wed Nov 30 11:30:54 CST 2011

CPU: ARMv7 Processor [412fc085] revision 5 (ARMv7), cr=10c53c7f

CPU: VIPT nonaliasing data cache, VIPT nonaliasing instruction cache

Machine: Freescale MX53 LOCO Board

Memory policy: ECC disabled, Data cache writeback

Built 1 zonelists in Zone order, mobility grouping on.  Total pages: 250880

Kernel command line: console=ttymxc0,115200 root=/dev/mmcblk0p1 rw rootfstype=ext3 rootwait video=mxcdi0fb:RGB24,1024x768M@60

PID hash table entries: 4096 (order: 2, 16384 bytes)

Dentry cache hash table entries: 131072 (order: 7, 524288 bytes)

Inode-cache hash table entries: 65536 (order: 6, 262144 bytes)

Memory: 480MB 512MB = 992MB total

Memory: 998300k/998300k available, 17508k reserved, 0K highmem

Virtual kernel memory layout:

    vector  : 0xffff0000 - 0xffff1000   (   4 kB)

    fixmap  : 0xfff00000 - 0xfffe0000   ( 896 kB)

    DMA     : 0xf9e00000 - 0xffe00000   (  96 MB)

    vmalloc : 0xe0800000 - 0xf4000000   ( 312 MB)

    lowmem  : 0x80000000 - 0xe0000000   (1536 MB)

    pkmap   : 0x7fe00000 - 0x80000000   (   2 MB)

    modules : 0x7f000000 - 0x7fe00000   (  14 MB)

      .init : 0x80008000 - 0x80033000   ( 172 kB)

      .text : 0x80033000 - 0x807e0000   (7860 kB)

      .data : 0x80804000 - 0x8085b4a0   ( 350 kB)

SLUB: Genslabs=11, HWalign=32, Order=0-3, MinObjects=0, CPUs=1, Nodes=1

Hierarchical RCU implementation.

.RCU-based detection of stalled CPUs is disabled.

.Verbose stalled-CPUs detection is disabled.

NR_IRQS:368MXC GPIO hardware

MXC IRQ initialized

MXC_Early serial console at MMIO 0x53fbc000 (options '115200')

bootconsole [ttymxc0] enabled

Console: colour dummy device 80x30

Calibrating delay loop... 799.53 BogoMIPS (lpj=3997696)

pid_max: default: 32768 minimum: 301

Mount-cache hash table entries: 512

CPU: Testing write buffer coherency: ok

Unhandled fault: alignment exception (0x001) at 0x8079112a

Internal error: : 1 [#1] PREEMPT

last sysfs file: 

Modules linked in:

CPU: 0    Not tainted  (2.6.35.3 #1)

PC is at devtmpfs_init+0xc/0xa4

LR is at driver_init+0x8/0x28

pc : [<8001dea4>]    lr : [<8001de54>]    psr: 80000013

sp : df039fd0  ip : 00000000  fp : 00000000

r10: 00000000  r9 : 00000000  r8 : 00000000

r7 : 00000013  r6 : 800349fc  r5 : 800088f0  r4 : 800321a8

r3 : 8079112a  r2 : 800a2218  r1 : 00000000  r0 : 8083f1fc

Flags: Nzcv  IRQs on  FIQs on  Mode SVC_32  ISA ARM  Segment kernel

Control: 10c5387f  Table: 70004019  DAC: 00000017

Process swapper (pid: 1, stack limit = 0xdf0382e8)

Stack: (0xdf039fd0 to 0xdf03a000)

9fc0:                                     00000000 00000000 800a2218 00000000

9fe0: 800321a8 8001de54 800321a8 8000896c 00000000 800349fc 01207b65 89251006

[<8001dea4>] (devtmpfs_init+0xc/0xa4) from [<8001de54>] (driver_init+0x8/0x28

[<8001de54>] (driver_init+0x8/0x28) from [<8000896c>] (kernel_init+0x7c/0x168

[<8000896c>] (kernel_init+0x7c/0x168) from [<800349fc>] (kernel_thread_exit+0x0/0x8)

Code: 8083f1ec e92d401f e59f3080 e59f0080 (e5932000)

 

The kernel eventually stops displaying output and appears to hang.  Has anyone encountered this kind of error booting the Freescale kernel?  I'm at a lose right now since I don't know what angle to attack this problem from.  Thanks in advance!

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