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Subject: Re: [PATCH -next] evm: Use IS_ENABLED to initialize .enabled
From:   Mimi Zohar <zohar@linux.ibm.com>
To:     Eric Biggers <ebiggers@kernel.org>
Cc:     xiujianfeng <xiujianfeng@huawei.com>,
        Ahmad Fatoum <a.fatoum@pengutronix.de>,
        dmitry.kasatkin@gmail.com, jmorris@namei.org, serge@hallyn.com,
        linux-integrity@vger.kernel.org,
        linux-security-module@vger.kernel.org, linux-kernel@vger.kernel.org
Date:   Sun, 26 Jun 2022 12:13:13 -0400
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References: <20220606101042.89638-1-xiujianfeng@huawei.com>
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         <812c4ee9-56f7-900a-df48-f3ca3e15542f@huawei.com>
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On Tue, 2022-06-21 at 19:17 -0700, Eric Biggers wrote:
> On Tue, Jun 21, 2022 at 10:03:39AM -0400, Mimi Zohar wrote:
> > On Tue, 2022-06-21 at 18:58 +0800, xiujianfeng wrote:
> > > Hi, Ahmad
> > > 
> > > 在 2022/6/7 14:06, Ahmad Fatoum 写道:
> > > > On 06.06.22 12:10, Xiu Jianfeng wrote:
> > > >> Use IS_ENABLED(CONFIG_XXX) instead of #ifdef/#endif statements to
> > > >> initialize .enabled, minor simplicity improvement.
> > 
> > The difference between using ifdef's and IS_ENABLED is when the
> > decision is made - build time, run time.   Please update the patch
> > description providing an explanation for needing to make the decision
> > at run time.
> > 
> > thanks,
> 
> IS_ENABLED() is a compile time constant.  So the patch looks fine to me.

Thanks, Eric, for the clarification.

As LSMs are only builtin, why the need for using IS_ENABLED as opposed
to IS_BUILTIN?

#define IS_ENABLED(option) __or(IS_BUILTIN(option), IS_MODULE(option))

thanks,

Mimi