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Re: [PATCH] Linux Kernel Markers


Martin Bligh wrote:
> You mean using the jump-over thing that was posted earlier?
> I thought the CPU erratas prevented doing that atomically
> properly. From my understanding of the last 24 hours discussion,
> it seemed like the ONLY thing we could do safely atomically was
> insert an int3. Which sucks, frankly, but still.

No. djprobes already does safely insert other stuff than just
int3, that's the whole point.

Here are the relevant postings by Hiramatsu-san:
http://marc.theaimsgroup.com/?l=linux-kernel&m=115875912510827&w=2
http://marc.theaimsgroup.com/?l=linux-kernel&m=115875867519302&w=2

Unless there's something *I* fundamentally misunderstood from
Hiramatsu-san's implementation and input, djprobes can replace
the 5-byte filler with a 5-byte unconditional jump. IOW your
mechanism works, no int3s involved.

Karim


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