Re: Fwd: [PATCH] kretprobe instance recycled by parent process

[bibo mao <bibo_mao@linux.intel.com>]

Zhou Yingchao wrote:
> > > > When kretprobe probe schedule() function, if probed process exit then
> > > > schedule() function will never return, so some kretprobe instance will
> > > > never be recycled. By this patch the parent process will recycle
> > > > retprobe instance of probed function, there will be no memory leak of
> > > > kretprobe instance. This patch is based on 2.6.16-rc3.
> > > Is there any process which can exit without go through the do_exit() path?
> > > --
> > When process exits through do_exit() function, it will call schedule()
> > function. But if schedule() function is probed by kretprobe, this time
> > schedule() function will not return never because process has exited.
> >
> > bibo,mao
>
> In the original path, doesn't the call path of
> do_exit()->exit_thread()->kprobe_flush_task(current) recycle the
> kretprobe instance? Is there anything misundstood?
> --
yes, it is right. The old recycle method is
   do_exit()->exit_thread()->kprobe_flush_task(current)
            ->schedule()
At last line of do_exit() it will call schedule() function, and this 
time it will never return. But if schedule function is probed, who is 
responsible for recycling it?

bibo,mao
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/