Hi,
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r1: c026ec90 r2: c0354000 r3: c0354000 r4: c0354000
r5: 00000001 r6: 00000000 r7: 00000000 r8: 00000000
r9: 00000008 r10: 00000171 r11: c035aacc r12: c0356a3c
r13: c0356a40 r14: ffffffe4 r15: c020d81c
ra: c026f520 fp: deadbeef sp: c025ef9c gp: deadbeef
ea: c026f614 estatus: 00000000
Unaligned access from kernel mode, this might be a hardware
problem, dump registers and restart the instruction
BADADDR 0xdeadbf0f
cause 7
op-code 0xb800283a
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Please get the objdump file from your 'vmlinux' and check the instruction that is located at '0xc026f614'. The opcode is really '0xb800283a' (0x**00283a means the 'ret' instruction, but 'b8' means that it refers r23 not ra) ? The exception code '7' means that the Nios2 CPU will jump to misaligned target '0xdeadbf0f'.
Kazu