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Date:   Wed, 15 Apr 2020 12:23:20 +0900
From:   Masami Hiramatsu <mhiramat@kernel.org>
To:     Vlastimil Babka <vbabka@suse.cz>
Cc:     Luis Chamberlain <mcgrof@kernel.org>,
        Kees Cook <keescook@chromium.org>,
        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>,
        Masami Hiramatsu <mhiramat@kernel.org>
Subject: Re: [PATCH 1/3] kernel/sysctl: support setting sysctl parameters
 from kernel command line
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On Tue, 14 Apr 2020 13:25:07 +0200
Vlastimil Babka <vbabka@suse.cz> wrote:

> On 4/6/20 7:08 PM, Luis Chamberlain wrote:
> > On Mon, Apr 06, 2020 at 08:58:50AM -0700, Kees Cook wrote:
> >> 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).
> > 
> > The *internal* aspect here is an extension to boot params under a
> > kconfig which would simply append to it, as if the user would have
> 
> So there's no such kconfig yet to apply boot parameters specified by configure,
> right? That would itself be a new feature. Or could we use bootconfig? (CC Masami)

Yes, I think you can use bootconfig to add this feature more flexibly.
I think your patch is easily modified to use bootconfig. :)

Thank you,

-- 
Masami Hiramatsu <mhiramat@kernel.org>