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Date: Tue, 23 Oct 2018 13:09:23 -0700
From: Matthew Wilcox <willy@infradead.org>
Subject: Re: [RFC PATCH 0/2] improve vmalloc allocation
Message-ID: <20181023200923.GB25444@bombadil.infradead.org>
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To: Shuah Khan <shuah@kernel.org>
Cc: Joel Fernandes <joel@joelfernandes.org>, Michal Hocko <mhocko@kernel.org>, Uladzislau Rezki <urezki@gmail.com>, Kees Cook <keescook@chromium.org>, Andrew Morton <akpm@linux-foundation.org>, linux-mm@kvack.org, LKML <linux-kernel@vger.kernel.org>, Thomas Garnier <thgarnie@google.com>, Oleksiy Avramchenko <oleksiy.avramchenko@sonymobile.com>, Steven Rostedt <rostedt@goodmis.org>, Joel Fernandes <joelaf@google.com>, Thomas Gleixner <tglx@linutronix.de>, Ingo Molnar <mingo@elte.hu>, Tejun Heo <tj@kernel.org>, maco@android.com

On Tue, Oct 23, 2018 at 01:48:32PM -0600, Shuah Khan wrote:
> On 10/23/2018 01:30 PM, Joel Fernandes wrote:
> > On Tue, Oct 23, 2018 at 11:13:36AM -0600, Shuah Khan wrote:
> >> I like this proposal. I think we will open up lot of test opportunities with
> >> this approach.
> >>
> >> Maybe we can use this stress test as a pilot and see where it takes us.
> > 
> > I am a bit worried that such an EXPORT_SYMBOL_KSELFTEST mechanism can be abused by
> > out-of-tree module writers to call internal functionality.
> 
> That is  valid concern to consider before we go forward with the proposal.
> 
> We could wrap EXPORT_SYMBOL_KSELFTEST this in an existing debug option. This could
> be fine grained for each sub-system for its debug option. We do have a few of these
> now

This all seems far more complicated than my proposed solution.