Messages in this thread | | | Date | Fri, 24 Jul 2015 09:03:42 -0400 | From | Steven Rostedt <> | Subject | Re: Dealing with the NMI mess |
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On Fri, 24 Jul 2015 14:43:04 +0200 Peter Zijlstra <peterz@infradead.org> wrote:
> > I'm not too familiar with how to use hw breakpoints, but I'm guessing > > (correct me if I'm wrong) that breakpoints on code that trigger when > > executed, but watchpoints on data trigger when accessed. Then > > copy_from_user_inatomic() would only trigger on watchpoints (it's not > > executing that code, at least I hope it isn't!), and those wont bother > > us. > > These things can be: RW, W, X. > > Sure, hitting a user X watchpoint is going to be 'interesting', but its > fairly easy to hit a RW one.
But do we care if we do hit one? The return from the #DB handler can use a RET. Right?
-- Steve
> > Just watch an on-stack variable and get perf to copy a huge chunk of > stack (like it does for the dwarf stuff).
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