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Re: [PATCH v2 2.6.38-rc8-tip 5/20] 5: Uprobes: register/unregister probes.


> > 
> > One of the install_uprobe could be failing because the process was
> > almost exiting, something like there was no mm->owner. Also lets
> > assume that the first few install_uprobes go thro and the last
> > install_uprobe fails. There could be breakpoint hits corresponding to
> > the already installed uprobes that get displayed. i.e all
> > breakpoint hits from the first install_uprobe to the time we detect a
> > failed a install_uprobe and revert all inserted breakpoints will be
> > shown as being captured.
> 
> I think you can gracefully deal with the exit case and simply ignore
> that one. But you cannot let arbitrary installs fail and still report
> success, that gives very weak and nearly useless semantics.

If there are more than one instance of a process running and if one
instance of a process has a probe thro ptrace, install_uprobe would fail
for that process with -EEXIST since we dont want to probe locations that
have breakpoints already. Should we then act similar to the exit case,
do we also deal gracefully?

-- 
Thanks and Regards
Srikar


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