* Masami Hiramatsu <mhiramat@xxxxxxxxxx> wrote: > Hi, > > Here are the patches of kprobe-based event tracer for x86, version 4. > > This version supports only x86(-32/-64) (If someone is interested in > porting this to other architectures, he just needs to port > kprobes/kretprobes and ptrace enhancement[PATCH 2/6]). > > I added x86 insn decoder on this version. It might be better > integrated with KVM's decoder, and kprobes x86 code should be > rewritten with it. > > > This can be applied on the linux-2.6-tip tree. > > This patchset includes following changes: > - Fix kernel_trap_sp() on x86 according to systemtap runtime. [1/6] > - Add arch-dep register and stack fetching functions [2/6] > - Add x86 instruction decoder [3/6] > - Check insertion point safety in kprobe [4/6] > - Add kprobe-tracer plugin [5/6] > - Support fetching various status (register/stack/memory/etc.) [6/6] ok, the structure and concept looks quite good now, really nice! I'm wondering about something i suggested many moons ago: to look into the KVM decoder+emulator (arch/x86/kvm/x86_emulate.c). I remember there were some issues with that (one problem being that the KVM decoder is a special-purpose thing covering specific range of execution environments - not a near-full integer-ops decoder like the one we are aiming for here) - are there any other fundamental problems beyond 'it has to be done' ? Conceptually we want just a single piece of decoder logic in arch/x86/. If the KVM folks are cool with it we could factor out the KVM one into arch/x86/lib/. But ... if there are compelling reasons to leave the KVM one alone in its limited environment we can do that too. Avi, Peter, what's your take on this? Ingo -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
