Hi Petr, (2015/02/27 1:13), Petr Mladek wrote: > arm_kprobe_ftrace() could fail, especially after introducing ftrace IPMODIFY > flag and LifePatching. This patch set adds the error handling and also some > related fixes.
Hmm, I'd like to drop IPMODIFY from kprobes except for jprobes, since it actually doesn't change regs->ip which was sent before. It seems that this series partly covers that work. > 1st patch includes the most important change. It helps to keep Kprobes > in a sane state. > > 2nd and 3rd patch allows to propagate the error where needed. OK, I think the 1st one could be merged. 2nd and 3rd one still have some issues as far as I reviewed. > The other patches fix problems with the global kprobes_all_disarmed flag. > They were there even before but they become more visible and critical > after the arming errors became propagated. Could you separate the series? And also I doubt we need to show global disable status, since we can check it via debugfs too (and looks redundant). Thank you, > The first patch looks rather safe and might be suitable even for 4.0. > > However, I would feel more comfortable if the other patches get some > testing in linux-next. I did quite some testing and did my best. But > I started with the three patches and was surprised by the effect of > the propagated errors. They triggered that BUG_ON() in > __unregister_kprobe_top() are required the other patches > to get it working. I wonder if there is any other scenario that > I have missed. > > Of course, I also wait for feedback how to make things better. > > > Petr Mladek (7): > kprobes: Disable Kprobe when ftrace arming fails > kprobes: Propagate error from arm_kprobe_ftrace() > kprobes: Propagate error from disarm_kprobe_ftrace() > kprobes: Keep consistent state of kprobes_all_disarmed > kprobes: Do not try to disarm already disarmed Kprobe > kprobes: Check kprobes_all_disarmed in kprobe_disarmed() > kprobes: Mark globally disabled Kprobes in debugfs interface > > Documentation/kprobes.txt | 5 +- > kernel/kprobes.c | 279 > ++++++++++++++++++++++++++++++++++------------ > 2 files changed, 213 insertions(+), 71 deletions(-) > -- Masami HIRAMATSU Software Platform Research Dept. Linux Technology Research 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/
