Problem Booting uClinux on DE2

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Can anyone help me? I'm trying to get uClinux running on a DE2 board. 

Ultimately, after making an image to download, the system does not fully boot. The symptoms are similar to a thread I found on the forum: "uClinux 20100621 - connecting NIOS HW with linux" but playing with the load offset and trimming down the kernel doesn't produce any different result.  Thanks in advance. D.W. Lynn  Here are the details: I'm using a Centos6 system. For the most part I have followed the current instructions on the wiki at "Linux for the Nios II Processor" I did step 1, adding a "yum install libuuid-devel" as I found (later) that libuuid.a was missing on my system. I also had to make a few minor changes to makefiles since my make is 3.82.  I found step 2 a bit confusing since it indicates that one should now install i"nios2-linux-20100621.tar". Is this necessary? This tarball contains what seems to be a subset of what was already installed in step 1. I skipped this step. I did go to nios2-linux/linux-2.6 and checked out the unstable-nios2mmu branch I then did ./checkout in nios2-linux. I then successfully went through step3 except I don't have a 3C120 system to test with.  At this point I setup an MMU based system for my DE2 board. Following the hints in step 4, I added 1KB of dual-port tightly-coupled on-chip memory and setup the caches and assigned the fast TLB miss exception vector to address 0 in the added on-chip memory. The system also has 8MB of SDRAM at address 0x10000000, a JTAG UART, a system timer, LED and switch ports and a University program clock module (which provides a PLL for SDRAM clock timing). Did I miss something? I wasn't able to find any reference to a minimal set of hardware requirements.  I then followed the step 8 devicetree instructions to build and include a dts file for my system. Some kernel config options were described differently, but I believe that I found and set them all. After configuring my .sof, I downloaded the zImage. It downloaded to 0xc1000000 through 0xc13f0000 and verified as indicated below: Using cable "USB-Blaster [1-1.1]", device 1, instance 0x00 Pausing target processor: OK Initializing CPU cache (if present) OK Downloaded 4009KB in 21.5s (186.4KB/s) Verified OK  Starting processor at address 0xC1000000 but did not boot, as indicated below:  [lynnd@Doug-new ~]$ nios2-terminal  nios2-terminal: connected to hardware target using JTAG UART on cable  nios2-terminal: "USB-Blaster [1-1.1]", device 1, instance 0  nios2-terminal: (Use the IDE stop button or Ctrl-C to terminate)   nios2-terminal: exiting due to ^C on host  You can see that it did not boot. If I download the vmlinux image, I get the following:  [lynnd@Doug-new ~]$ nios2-download -g nios2-linux/uClinux-dist/images/vmlinux  Using cable "USB-Blaster [1-1.1]", device 1, instance 0x00 Pausing target processor: OK Initializing CPU cache (if present) OK Downloaded 2795KB in 14.9s (187.5KB/s) Verified OK  Starting processor at address 0xC0000000 [lynnd@Doug-new ~]$ nios2-terminal nios2-terminal: connected to hardware target using JTAG UART on cable nios2-terminal: "USB-Blaster [1-1.1]", device 1, instance 0 nios2-terminal: (Use the IDE stop button or Ctrl-C to terminate)  Linux version 3.1.0-rc4-01162-g45c9dd8 (lynnd@Doug-new.faculty.cset.oit.edu) (gcc version 4.1.2)# 8 Mon Nov 5 16:25:58 PST 2012 bootconsole [early0] enabled early_console initialized at 0xe1411050 On node 0 totalpages: 8192 free_area_init_node: node 0, pgdat c02bb060, node_mem_map c02d0a20  DMA zone: 64 pages used for memmap  DMA zone: 0 pages reserved  DMA zone: 8128 pages, LIFO batch:0 pcpu-alloc: s0 r0 d32768 u32768 alloc=1*32768 pcpu-alloc: [0] 0  Built 1 zonelists in Zone order, mobility grouping on. Total pages: 8128 Kernel command line: debug console=ttyJ0,115200 PID hash table entries: 128 (order: -3, 512 bytes) Dentry cache hash table entries: 4096 (order: 2, 16384 bytes) Inode-cache hash table entries: 2048 (order: 1, 8192 bytes) Memory available: 29568k/2874k RAM (2191k kernel code, 682k data) NR_IRQS:32 Unable to handle kernel NULL pointer dereference at virtual address 00000000 ea = c0227c7c, ra = c0227c4c, cause = 15 Kernel panic - not syncing: Oops