Re: [RFC][PATCH] tracing, printk: Force no hashing when trace_printk() is used

From: Steven Rostedt
Date: Tue Apr 03 2018 - 18:59:46 EST


On Wed, 4 Apr 2018 07:43:49 +1000
"Tobin C. Harding" <me@xxxxxxxx> wrote:

> > static noinline_for_stack
> > char *restricted_pointer(char *buf, char *end, const void *ptr,
> > @@ -1962,6 +1963,10 @@ char *pointer(const char *fmt, char *buf, char *end, void *ptr,
> > return pointer_string(buf, end, ptr, spec);
> > }
> >
> > + /* When the kernel is in debugging mode, show all pointers */
> > + if (static_key_false(&trace_debug))
> > + return restricted_pointer(buf, end, ptr, spec);
> > +
> > /* default is to _not_ leak addresses, hash before printing */
> > return ptr_to_id(buf, end, ptr, spec);
> > }
>
> This uses the deprecated API Steve (I only know because I went to read
> Documentation/static-keys.txt after seeing this patch).

Hmm, I've been involved with static keys since it was introduced. I
simply copied the code for the original use case (tracepoints). I
forgot that we are changing the name (this has been an ongoing bikeshed
for some time, I can't keep up. Better than the original suggestion
"really_unlikely()" ;)

I need to update tracepoints too.

-- Steve