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Date:   Tue, 5 Feb 2019 20:08:50 +0100
From:   Wolfram Sang <wsa@the-dreams.de>
To:     John Sperbeck <jsperbeck@google.com>
Cc:     Steven Rostedt <rostedt@goodmis.org>,
        Ingo Molnar <mingo@redhat.com>, linux-i2c@vger.kernel.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH] i2c: core-smbus: don't trace smbus_reply data on errors
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> > > Hmm, instead of tracing nothing, as this is already a "conditional
> > > trace event", why not add to that condition:
> > >
> > >       TP_CONDITION(res >=3D 0 && read_write =3D=3D I2C_SMBUS_READ),
> > >
> > > Unless you want to still trace some data on failure.
> >
> > John, any comment to this?
> >
>=20
> The issue we were dealing with was access to uninitialized memory on the =
stack.
> The change '30f939feaeee i2c: fix kernel memory disclosure in dev interfa=
ce'
> does the initialization, so the tracing code is no longer affected.
> We just didn't
> have that change in the particular kernel we were testing.
>=20
> Still, Steven's suggestion seems fine to me.  Would you like me to create=
 a new
> patch based on that?

I am not a tracing expert, but all that was said here tell me that it
would be better to have the change. So, yes, please, that would be
appreciated.


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