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From: Xiao Guangrong <guangrong.xiao@gmail.com>
Subject: Is read barrier missed in kfifo?
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Date: Fri, 11 May 2018 15:25:18 +0800
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Hi,

Currently, there is no read barrier between reading the index
(kfifo.in) and fetching the real data from the fifo.

I am afraid that will cause the vfifo is observed as not empty
however the data is not actually ready for read. Right?

Thanks!