Messages in this thread | | | Date | Thu, 21 Nov 2013 11:14:55 +0900 | From | Masami Hiramatsu <> | Subject | Re: [PATCH -tip v3 00/23] kprobes: introduce NOKPROBE_SYMBOL() and general cleaning of kprobe blacklist |
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(2013/11/21 2:36), Frank Ch. Eigler wrote: > Hi - > >>> Does this new blacklist cover enough that the kernel now survives a >>> broadly wildcarded perf-probe, e.g. over e.g. all of its kallsyms? >> >> That's generally the purpose of the annotations - if it doesn't then >> that's a bug. > > AFAIK, no kernel since kprobes was introduced has ever stood up to > that test. perf probe lacks the wildcarding powers of systemtap, so > one needs to resort to something like: > > # cat /proc/kallsyms | grep ' [tT] ' | while read addr type symbol; do > perf probe $symbol > done > > then wait for a few hours for that to finish. Then, or while the loop > is still running, run > > # perf record -e 'probe:*' -aR sleep 1 > > to take a kernel down.
Um, indeed, current blacklist is not perfect. As I reported in this series, I've found 2 more patterns. I guess there still have some others.
But anyway, I don't think it is good to fix all such bugs in this series. This is just the first step to do it. :)
Thank you,
-- Masami HIRAMATSU IT Management Research Dept. Linux Technology Center Hitachi, Ltd., Yokohama Research Laboratory E-mail: masami.hiramatsu.pt@hitachi.com
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