On Mon, 7 Jan 2019 19:34:44 +0100 Andrea Righi <righi.and...@gmail.com> wrote:
> On Mon, Jan 07, 2019 at 10:31:34PM +0900, Masami Hiramatsu wrote: > ... > > BTW, this is not all of issues. To remove CONFIG_KPROBE_EVENTS_ON_NOTRACE > > I'm trying to find out other notrace functions which can cause > > kernel crash by probing. Mostly done on x86, so I'll post it > > after this series. > > Not sure if you found it already, but it looks like some of the > _raw_spin_lock/unlock* functions (when they're not inlined) are causing > the same problem (or something similar), I can deadlock the system by > doing this for example: > > echo "r:event_1 __fdget" >> kprobe_events > echo "r:event_2 _raw_spin_lock_irqsave" >> kprobe_events > echo 1 > events/kprobes/enable > [DEADLOCK] > > Sending the following just in case... > Ug, kretprobe calls spinlocks in the callback? I wonder if we can remove them. I'm guessing this is a different issue than the one that this patch fixes. This sounds like we are calling kretprobe from kretprobe? -- Steve