Re: x86/kprobes: kretprobe fails to triggered if kprobe at function entry is not optimized (trigger by int3 breakpoint)

From: peterz
Date: Thu Aug 27 2020 - 05:02:35 EST


On Tue, Aug 25, 2020 at 10:15:55PM +0900, Masami Hiramatsu wrote:

> Yeah, kretprobe already provided the per-instance data (as far as
> I know, only systemtap depends on it). We need to provide it for
> such users.

Well, systemtap is out of tree, we don't _need_ to provide anything for
them. Furthermore, the function-graph tracer's ret_stack, which you said
you wanted to integrate with, also doesn't provide this.

Ditching it makes things simpler in that all kretprobe_instance's will
be the same and we no longer need per kretprobe storage of them.

Anyway, let me try and preserve them for now...