Re: [PATCH v5] tracepoint: Do not fail unregistering a probe due to memory failure

[Alexey Kardashevskiy]

On 31/01/2021 01:42, Steven Rostedt wrote:
> On Sat, 30 Jan 2021 09:36:26 -0500
> Steven Rostedt <rostedt@xxxxxxxxxxx> wrote:
>
> > Do you still have the same crash with v3 (that's the one I'm going to
> > go with for now.)
> >
> >   https://lore.kernel.org/r/20201118093405.7a6d2290@xxxxxxxxxxxxxxxxxx
>
> Just curious, does the following patch fix it for v5?


Yes it does!


> -- Steve
>
> diff --git a/kernel/tracepoint.c b/kernel/tracepoint.c
> index 7261fa0f5e3c..cf3a6d104fdb 100644
> --- a/kernel/tracepoint.c
> +++ b/kernel/tracepoint.c
> @@ -306,6 +306,7 @@ static int tracepoint_remove_func(struct tracepoint *tp,
>   			tp->unregfunc();
>   
>   		static_key_disable(&tp->key);
> +		tracepoint_synchronize_unregister();
>   		rcu_assign_pointer(tp->funcs, tp_funcs);
>   	} else {
>   		rcu_assign_pointer(tp->funcs, tp_funcs);

--
Alexey