Messages in this thread | | | Subject | Re: [BUG?]3.0-rc4+ftrace+kprobe: set kprobe at instruction 'stwu' lead to system crash/freeze | From | Benjamin Herrenschmidt <> | Date | Fri, 02 Dec 2011 08:37:48 +1100 |
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On Thu, 2011-12-01 at 18:44 +0800, tiejun.chen wrote:
> Do you mean we should push the original pt_regs (or that whole exception stack) > downwards the location the new r1 point? Then its safe to perform this real > emulated stw instruction. At last we will reroute r1 to that copied exception > frame to restore as normal. Right?
Right. That way we don't have to modify the (sensitive) restore path, we only hook around the do_work branch which is a lot easier and less risky.
> Here I suppose so, I implement this for PPC32 based on the above understanding. > I take a validation for kprobing do_fork()/show_interrupts(), now looks fine. > Tomorrow I will go PPC64, and hope its fine as well. > > If everything is good I'll send these patches to linuxppc-dev next week.
Excellent, thanks !
Cheers, Ben.
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