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Date:   Thu, 23 Jan 2020 10:53:40 -0500
From:   "Theodore Y. Ts'o" <tytso@mit.edu>
To:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc:     Jason Baron <jbaron@akamai.com>, Will Deacon <will@kernel.org>,
        linux-kernel@vger.kernel.org, kernel-team@android.com
Subject: Re: [PATCH v3] dynamic_debug: allow to work if debugfs is disabled
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On Wed, Jan 22, 2020 at 08:31:18PM +0100, Greg Kroah-Hartman wrote:
> With the realization that having debugfs enabled on "production" systems is
> generally not a good idea, debugfs is being disabled from more and more
> platforms over time.  However, the functionality of dynamic debugging still is
> needed at times, and since it relies on debugfs for its user api, having
> debugfs disabled also forces dynamic debug to be disabled.
> 
> To get around this, move the "control" file for dynamic_debug to procfs IFF
> debugfs is disabled.  This lets people turn on debugging as needed at runtime
> for individual driverfs and subsystems.

Instead of moving the control file IFF debugfs is enabled, what about
always making it available in /proc, and marking the control file for
dynamic_debug in debugfs as deprecated?  It would seem to me that this
would cause less confusion in the future....

					- Ted