On Wed, 6 Jul 2011, Tixy wrote:
On Wed, 2011-07-06 at 18:09 +0100, Dave Martin wrote:
Good point -- presumably the kprobes already refuses to set a probe if the target location already contains the opcode used for a kprobe trap?
It will do for ARM, because you're probing an undefined instruction. Other architecture can have optimised probes which use branches rather rather breakpoints.
The point is that we don't have to care about this case even if the generic kprobes code might be fooled by the same address presented with and without the Thumb bit since the second attempt will be refused and nothing nasty will occur.
Nicolas