On Tue, 29 Mar 2011, Russell King - ARM Linux wrote:

On Tue, Mar 29, 2011 at 12:55:27PM -0400, Nicolas Pitre wrote:

quoted

Sorry, I meant r15-indexed with a write back.

I believe that's unpredictable.  So actually you can make kprobes do
anything you like with it - no one should ever generate an instruction
which read-modify-writes the PC.

Indeed.  Hence my suggestion to simply refuse and abort the placement of 
a probe on such instructions and keep the actual emulation code free of 
tests for those odd cases.  In practice this shouldn't affect anyone.


Nicolas