Re: kernel BUG at net/rxrpc/local_object.c:LINE!

From: Dmitry Vyukov
Date: Tue Aug 13 2019 - 10:28:43 EST


On Tue, Aug 13, 2019 at 4:23 PM David Howells <dhowells@xxxxxxxxxx> wrote:
>
> Dmitry Vyukov <dvyukov@xxxxxxxxxx> wrote:
>
> > > > Please send a patch for testing that enables this tracing
> > > > unconditionally. This should have the same effect. There is no way to
> > > > hook into a middle of the automated process and arbitrary tune things.
> > >
> > > I don't know how to do that off hand. Do you have an example?
> >
> > Few messages above I asked it to test:
> > https://groups.google.com/d/msg/syzkaller-bugs/gEnZkmEWf1s/r2_X_KVQAQAJ
> >
> > Basically, git repo + branch + patch. Here are the docs:
> > https://github.com/google/syzkaller/blob/master/docs/syzbot.md#testing-patches
>
> I meant that I don't know how to turn a tracepoint on from inside the kernel.

This /sys/kernel/debug/tracing/events/rxrpc/rxrpc_local/enable in:
echo 1 > /sys/kernel/debug/tracing/events/rxrpc/rxrpc_local/enable
should map to some global variable, right? If so, it should be
possible to initialize that var to 1 statically. Or that won't work
for some reason?