Get instruction opcode + operands for page fault

Adam Lackorzynski adam at
Sun Feb 4 23:58:13 CET 2018


On Fri Feb 02, 2018 at 14:32:08 +0100, Josef Stark wrote:
> when a page fault occurs, does the Instruction Register contain the actual
> instruction that caused the fault or the previous instruction? In the former
> case, how can I access it? I need the opcode + the operands (like
> source/target registers). I already have the memory address that the
> instruction tried to access.
> I'm on ARM A9, so only load/store instructions can cause a page fault.
> I know that I could also look at the address where my IP is pointing to and
> get the instruction from there, but I'm wondering which way would be
> easier/better.

There is no register that contains the opcode of the instruction that
caused a fault. You have to read the instruction yourself if you're
interested in decoding the instruction.


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