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From: Dou Liyang <douly.fnst@cn.fujitsu.com>
Subject: irqdesc: Why the "__ref" is needed in __irq_alloc_descs() ?
To: Thomas Gleixner <tglx@linutronix.de>,
        Kees Cook <keescook@chromium.org>, <re.emese@gmail.com>,
        Marc Zyngier <marc.zyngier@arm.com>
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Date: Fri, 9 Mar 2018 15:07:47 +0800
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Hi Maintainers,

I have a question about "__ref" in Linux kernel.

When I looked into the __irq_alloc_descs(), I found it tagged a
"__ref" mark, but I didn't find that it referenced code or data
from init section.

So, I confuse why the "__ref"  is needed in __irq_alloc_descs()?
any other reasons?

And after I tested, seems "__ref" just puts the code into a different
section that is not checked by modpost. It does not affect the
performance whether it is tagged or not. Is it right?

Thanks,
	dou.