Re: [PATCH 2/4] ftrace/instances: Clear function triggers when removing instances

Masami Hiramatsu
2017-05-16T16:11:28Z

On Mon, 15 May 2017 12:11:03 -0400
Steven Rostedt <rostedt@goodmis.org> wrote:

> On Mon, 15 May 2017 11:21:15 -0400
> Steven Rostedt <rostedt@goodmis.org> wrote:
>
> > On Sun, 14 May 2017 01:01:02 +0530
> > "Naveen N. Rao" <naveen.n.rao@linux.vnet.ibm.com> wrote:
> >
> > > If instance directories are deleted while there are registered function
> > > triggers:
> > >
> > > # cd /sys/kernel/debug/tracing/instances
> > > # mkdir test
> > > # echo "schedule:enable_event:sched:sched_switch" > test/set_ftrace_filter
> > > # rmdir test
> > > Unable to handle kernel paging request for data at address 0x00000008
> > > Unable to handle kernel paging request for data at address 0x00000008
> > > Faulting instruction address: 0xc0000000021edde8
> > > Oops: Kernel access of bad area, sig: 11 [#1]
> > > SMP NR_CPUS=2048
> > > NUMA
> > > pSeries
> >
> > Looks like this patch needs to be marked for stable, and go in right
> > away. I may also do the same for the ftracetest bashism patch with
> > Masami's approval. I may also slip in the ftracetest for the bug that
> > this patch fixes.
>
> As this patch fixes a bug that was introduced with the 4.12 merge
> window. Thus, it's not stable worthy (stable isn't affected). Although,
> I'll wait on Masami to see if that should go to stable.

Hm, for the bashism fix, that is not a show-stopper... and also,
newer ftracetest should work on older kernel. So I don't think
it needs to go stable.

Thank you,

>
> -- Steve
>

--
Masami Hiramatsu <mhiramat@kernel.org>