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Re: [RFC] [PATCH 2.6.37-rc5-tip 13/20] 13: x86: x86 specific probe handling


Hi Roland,

> > But I'll leave this to the x86 people who actually know the intricacies
> > of the single step cruft, I was just wondering why you weren't using (or
> > extending) the existing code.
> 
> The hairy aspects of the step.c code are hairy (and not usable at interrupt
> level) because they do some instruction analysis.  Since uprobes already
> does its own instruction analysis, reusing step.c's separate hacks makes
> less sense to me than integrating knowledge of the single-step vs
> pushf/popf issues into the uprobes instruction analysis.
> 
> That said, there is further nontriviality just to do with the block-step
> support and with not clobbering user-visible usage of TF in eflags, which
> uprobes needs to handle as well.  It makes sense to share that code rather
> than repeating it, even if that entails changes to the step.c code.
> 

Uprobes doesn't request/handle block-step for now. So can we postpone
your suggested changes till uprobes needs to handle block-step?

-- 
Thanks and Regards
Srikar


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