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

From: Steven Rostedt
Date: Mon May 15 2017 - 12:11:13 EST


On Mon, 15 May 2017 11:21:15 -0400
Steven Rostedt <rostedt@xxxxxxxxxxx> wrote:

> On Sun, 14 May 2017 01:01:02 +0530
> "Naveen N. Rao" <naveen.n.rao@xxxxxxxxxxxxxxxxxx> 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.

-- Steve