linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To: "Theodore Y. Ts'o" <tytso@mit.edu>
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
Date: Fri, 24 Jan 2020 08:29:40 +0100	[thread overview]
Message-ID: <20200124072940.GA2909311@kroah.com> (raw)
In-Reply-To: <20200124060200.GG147870@mit.edu>

On Fri, Jan 24, 2020 at 01:02:00AM -0500, Theodore Y. Ts'o wrote:
> On Thu, Jan 23, 2020 at 06:55:36PM +0100, Greg Kroah-Hartman wrote:
> > > 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....
> > 
> > Why deprecate it?  It's fine where it is, and most developer's have
> > debugfs enabled so all is good.  I'd rather only use /proc as a
> > last-resort.
> 
> This makes life difficult for scripts that manipulate the control
> file, since they now need to check two different locations -- either
> /sys/kernel/debug or /proc.

That is literally 2 extra lines in a script file.  If you point me at
any that actually used the existing control file, I will be glad to fix
them up :)

> It's likely that people who normally use
> distribution kernels where debugfs is disabled will have scripts which
> are hard-coded to look in /proc, and then when they build a kernel
> with debugfs enabled, the /proc entry will go **poof**, and their
> script will break.

**poof** they didn't test it :)

Seriously, I am doing this change to make it _easier_ for those people
who want debugfs disabled, yet want this type of debugging.  This is
much better than having no debugging at all.

Don't put extra complexity in the kernel for when it can be trivially
handled in userspace, you know this :)

thanks,

greg k-h

  reply	other threads:[~2020-01-24  7:30 UTC|newest]

Thread overview: 26+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-01-22  7:43 [PATCH] dynamic_debug: allow to work if debugfs is disabled Greg Kroah-Hartman
2020-01-22  8:03 ` Will Deacon
2020-01-22  8:12   ` Greg Kroah-Hartman
2020-01-22 13:53     ` [PATCH v2] " Greg Kroah-Hartman
2020-01-22 18:56       ` Jason Baron
2020-01-22 19:29         ` Greg Kroah-Hartman
2020-01-22 19:31           ` [PATCH v3] " Greg Kroah-Hartman
2020-01-22 21:43             ` Randy Dunlap
2020-01-23  8:48               ` Greg Kroah-Hartman
2020-01-23  8:50                 ` [PATCH v4] " Greg Kroah-Hartman
2020-01-23  9:36                   ` Will Deacon
2020-01-23 15:53             ` [PATCH v3] " Theodore Y. Ts'o
2020-01-23 17:55               ` Greg Kroah-Hartman
2020-01-24  6:02                 ` Theodore Y. Ts'o
2020-01-24  7:29                   ` Greg Kroah-Hartman [this message]
2020-01-25  1:42                     ` Theodore Y. Ts'o
2020-01-25 17:11                       ` Jonathan Corbet
2020-01-27 22:19                         ` Saravana Kannan
2020-02-09 11:05               ` [PATCH v5] " Greg Kroah-Hartman
2020-02-09 15:53                 ` Joe Perches
2020-02-09 17:03                   ` Greg Kroah-Hartman
2020-02-10 21:11                 ` [PATCH v6] " Greg Kroah-Hartman
2020-02-10 21:15                   ` Randy Dunlap
2020-02-12 21:58                     ` Greg Kroah-Hartman
2020-02-11 11:01                   ` Will Deacon
2020-01-25  0:03 ` [PATCH] " kbuild test robot

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20200124072940.GA2909311@kroah.com \
    --to=gregkh@linuxfoundation.org \
    --cc=jbaron@akamai.com \
    --cc=kernel-team@android.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=tytso@mit.edu \
    --cc=will@kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).