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Date:   Mon, 6 Apr 2020 08:58:50 -0700
From:   Kees Cook <keescook@chromium.org>
To:     Luis Chamberlain <mcgrof@kernel.org>
Cc:     Vlastimil Babka <vbabka@suse.cz>,
        Iurii Zaikin <yzaikin@google.com>,
        linux-kernel@vger.kernel.org, linux-api@vger.kernel.org,
        linux-mm@kvack.org, Ivan Teterevkov <ivan.teterevkov@nutanix.com>,
        Michal Hocko <mhocko@kernel.org>,
        David Rientjes <rientjes@google.com>,
        Matthew Wilcox <willy@infradead.org>,
        "Eric W . Biederman" <ebiederm@xmission.com>,
        "Guilherme G . Piccoli" <gpiccoli@canonical.com>,
        Alexey Dobriyan <adobriyan@gmail.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Christian Brauner <christian.brauner@ubuntu.com>
Subject: Re: [PATCH 1/3] kernel/sysctl: support setting sysctl parameters
 from kernel command line
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On Mon, Apr 06, 2020 at 02:08:36PM +0000, Luis Chamberlain wrote:
> > Yes. Doing an internal extension isn't testing the actual code.
> 
> But it would.
> 
> [...]
> > I don't think anything is needed for this series. It can be boot tested
> > manually.
> 
> Why test it manually when it could be tested automatically with a new kconfig?

So, my impression is that adding code to the internals to test the
internals isn't a valid test (or at least makes it fragile) because the
test would depend on the changes to the internals (or at least depend on
non-default non-production CONFIGs).

Can you send a patch for what you think this should look like? Perhaps
I'm not correctly imagining what you're describing?

Regardless of testing, I think this series is ready for -mm.

-- 
Kees Cook