(2013/11/12 19:55), Sandeepa Prabhu wrote: >>>>> Thanks for steps, ARM64 ftrace patches are under review on arm mailing >>>>> list, I can contact the (linaro) developer implementing ftrace on >>>>> what's supported and then figure-out a way to test this concurrency of >>>>> kprobes breakpoint and hardware breakpoint. >>>> >>>> Would you mean this? :) >>>> http://www.spinics.net/lists/arm-kernel/msg278477.html >>>> >>>> Wow, it seems that this also has some works around instruction >>>> manipulation (and confusable filenames...) >>> I referred to: http://lwn.net/Articles/572323/ which is another >>> implementation and on LAKML >> >> OK, I'll check that (and looks good at a glance). >> By the way, I concern about Linaro guys who looks working a bit far >> from the LKML and original feature maintainers. Please contact them, >> I'm sure they don't bite your hand :) > Hmm sure, will convey to our developers/leads :-)
Nice :) >> BTW, I'm currently trying a general housecleaning of __kprobes >> annotations. It may also have impact on your patch. >> https://lkml.org/lkml/2013/11/8/187 > Hmm, we can help testing your patchset on arm64 platforms. Also have > many doubts on the changes you are working [blacklisting probes etc] > > Basically I had tried placing kprobe on memcpy() and the model hung > (insmod never returned back!). Fast-model I have does not have option > of any debug so no clue what happened!. On x86, I can probe memcpy() safely. It depends on the kprobes (and breakpoint handling) implementation, and it could be found. > memcpy() is low-level call being used internally within kprobes, so > probably we cannot handle probe on that routine, but then how to make > sure all such API are rejected by kprobe sub-system ? I see, the blacklist still needs to be maintained. I periodically run a test for probing each function on my kernel, and if I found such problem, I added it on the blacklist. Currently I run the test only on x86, so perhaps, other arch does not have well tested yet. Thank you, -- Masami HIRAMATSU IT Management Research Dept. Linux Technology Center Hitachi, Ltd., Yokohama Research Laboratory E-mail: masami.hiramatsu...@hitachi.com -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
