Hello Brad, hello list, I got a couple of minutes to play around with our multi platform kernel on the Utilite device. Since I have a workaround for the u-boot issues, I am able to load and execute a kernel and debug that. As expected there are some issues when the device is booting up. The kernel crashes right at the start. Please see the console output below. My assumption is that the kernel tries to access the part of the memory where the device tree file has been copied to by the bootloader. Some grsec mechanism tries to intervene and kill the kernel. I hope that Brad can help us with that. It appears that other systems boot fine with device tree. I currently cannot confirm that Wandboard which booted with an earlier development version of kernel still boots. Pandaboard (without device tree) does boot perfectly. Kernel sources: http://git.ipfire.org/?p=people/arne_f/kernel.git;a=shortlog;h=refs/heads/linux-3.10.x-grsecurity-2.9.1 Kernel config: http://git.ipfire.org/?p=ipfire-2.x.git;a=blob;f=config/kernel/kernel.config.armv5tel-ipfire-multi;h=128742d4681bac3ce80a55103f5516b0f636d871;hb=refs/heads/next Thanks for your help in advance. -Michael mmc2 is current device reading boot.scr 324 bytes read in 12 ms (26.4 KiB/s) ## Executing script at 13800000 reading zImage-ipfire-multi 3163176 bytes read in 210 ms (14.4 MiB/s) reading uInit-ipfire-multi 2237636 bytes read in 143 ms (14.9 MiB/s) reading board.dtb 22996 bytes read in 37 ms (606.4 KiB/s) Kernel image @ 0x10800000 [ 0x000000 - 0x304428 ] ## Loading init Ramdisk from Legacy Image at 11800000 ... Image Name: Image Type: ARM Linux RAMDisk Image (lzma compressed) Data Size: 2237572 Bytes = 2.1 MiB Load Address: 00000000 Entry Point: 00000000 Verifying Checksum ... OK ## Flattened Device Tree blob at 14800000 Booting using the fdt blob at 0x14800000 Loading Ramdisk to 4fddd000, end 4ffff484 ... OK Loading Device Tree to 4fdd4000, end 4fddc9d3 ... OK Starting kernel ... Uncompressing Linux... done, booting the kernel. Booting Linux on physical CPU 0x0 Initializing cgroup subsys cpuset Initializing cgroup subsys cpu Initializing cgroup subsys cpuacct Linux version 3.10.27-ipfire-multi (root(a)hokey.ipfire.org) (gcc version 4.4.7 (GCC) ) #1 SMP Fri Jan 17 00:38:17 GMT 2014 CPU: ARMv7 Processor [412fc09a] revision 10 (ARMv7), cr=10c5387d CPU: PIPT / VIPT nonaliasing data cache, VIPT aliasing instruction cache Machine: Freescale i.MX6 Quad/DualLite (Device Tree), model: CompuLab CM-FX6 bootconsole [earlycon0] enabled cma: CMA: reserved 16 MiB at 3e800000 Memory policy: ECC disabled, Data cache writealloc Unable to handle kernel paging request at virtual address ffdd4000 pgd = c0004000 [ffdd4000] *pgd=00000000 Internal error: Oops: 5 [#1] SMP ARM Modules linked in: CPU: 0 PID: 0 Comm: swapper Not tainted 3.10.27-ipfire-multi #1 task: c0b0d608 ti: c0b00000 task.ti: c0b00000 PC is at __unflatten_device_tree+0x70/0x2d0 LR is at unflatten_device_tree+0x24/0x3c pc : [] lr : [] psr: 600001d3 sp : c0b01f30 ip : c05b6028 fp : c0b01f64 r10: c082edf0 r9 : c2233200 r8 : c0a05d98 r7 : c0b0e880 r6 : c0be9620 r5 : ffdd4000 r4 : c0b65c18 r3 : 0000feed r2 : c0a05d98 r1 : c0c18d58 r0 : ffdd4000 Flags: nZCv IRQs off FIQs off Mode SVC_32 ISA ARM Segment kernel Control: 10c5387d Table: 1000404a DAC: 00000011 Process swapper (pid: 0, stack limit = 0xc0b00240) Stack: (0xc0b01f30 to 0xc0b02000) 1f20: ffffffff c0b1c498 c0c18d58 c0134078 1f40: c0b01f6c c0a05d98 80000200 c0be9620 c0b0e880 c0b1c498 c0b01f7c c0b01f68 1f60: c0a3d928 c05b601c c0a460c0 80000200 c0b01fb4 c0b01f80 c0a04b5c c0a3d910 1f80: c0393128 10c5387d c082cfdc ffffffff c0b67200 00000001 c0b0e69c 00000000 1fa0: 412fc09a 00000000 c0b01ff4 c0b01fb8 c0a00a5c c0a04574 00000000 00000000 1fc0: 00000000 00000000 d278bdb0 c0a4eb38 00000000 10c5387d c0b084a4 c0a4eb34 1fe0: c0b0e69c 1000406a 00000000 c0b01ff8 10008074 c0a009a8 00000000 00000000 [] (__unflatten_device_tree+0x70/0x2d0) from [] (unflatten_device_tree+0x24/0x3c) [] (unflatten_device_tree+0x24/0x3c) from [] (setup_arch+0x5f4/0x70c) [] (setup_arch+0x5f4/0x70c) from [] (start_kernel+0xc0/0x374) [] (start_kernel+0xc0/0x374) from [<10008074>] (0x10008074) Code: e1d43db2 e3130004 1a000059 e30f3eed (e5952000) ---[ end trace a2123bb2ee168675 ]--- Kernel panic - not syncing: grsec: halting the system due to suspicious kernel crash caused by root