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Date:   Thu, 20 May 2021 15:16:35 -0700
From:   Jeff Johnson <jjohnson@codeaurora.org>
To:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc:     linux-wireless@vger.kernel.org, Kalle Valo <kvalo@codeaurora.org>,
        "David S. Miller" <davem@davemloft.net>,
        Jakub Kicinski <kuba@kernel.org>,
        Kees Cook <keescook@chromium.org>,
        Jason Gunthorpe <jgg@ziepe.ca>, Chao Yu <chao@kernel.org>,
        Leon Romanovsky <leon@kernel.org>
Subject: Re: [PATCH v2] b43: don't save dentries for debugfs
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On 2021-05-19 09:03, Greg Kroah-Hartman wrote:
> On Wed, May 19, 2021 at 08:57:00AM -0700, Jeff Johnson wrote:
>> Unless debugfs is disabled, like on Android, which is the real problem 
>> I'm
>> trying to solve.
> 
> Then use some other filesystem to place your relay file in.  A relay
> file is not a file that userspace should rely on for normal operation,
> so why do you need it at all?
> 
> What tools/operation requires access to this file that systems without
> debugfs support is causing problems on?

(trimmed some lists)

For the ath drivers (as well as the out-of-tree Android driver) it is 
being used for RF spectral scan which produces a large amount of data 
that is processed by a userspace analysis application.

I've been looking for an alternate filesystem to use, but am not finding 
anything where it appears easy to get a parent dentry, so any clues for 
the clueless (me) would be appreciated.

Jeff

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