Date: Wed, 10 Dec 2014 21:49:17 +0100
From: David =?iso-8859-1?Q?H=E4rdeman?= <david@hardeman.nu>
To: "J. Bruce Fields" <bfields@fieldses.org>
Cc: linux-nfs@vger.kernel.org, SteveD@redhat.com
Subject: Re: [PATCH 00/19] gssd improvements
Message-ID: <20141210204917.GA11396@hardeman.nu>
References: <20141209053828.24756.89941.stgit@zeus.muc.hardeman.nu>
 <20141210203511.GF20235@fieldses.org>
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On Wed, Dec 10, 2014 at 03:35:11PM -0500, J. Bruce Fields wrote:
>On Tue, Dec 09, 2014 at 06:40:40AM +0100, David H?rdeman wrote:
>> The following series converts gssd to use libevent and inotify instead
>> of a handrolled event loop and dnotify. Lots of cleanups in the process
>> (e.g. removing a lot of arbitrary limitations and fixed size buffers).
>> 
>> All in all a nice reduction in code size (what can I say, I was bored).
>
>This code has been crying out for help for a while, thanks for taking a
>look!

:)

>On dnotify/inotify: if I remember correctly, this was written before
>inotify existed.  So you're probably breaking compatibility with older
>kernels, which we normally try not to do.

Fair enough...but...there has to be some kind of reasonable limit to
that. Like...unmaintained kernel versions with known CVEs...if an
organization is *that* conservative...I kinda doubt they'd update
nfs-utils either?

>According to inotify(7):
>
>	Inotify  was merged into the 2.6.13 Linux kernel.  The required
>	library interfaces were  added  to  glibc  in  version  2.4.
>	(IN_DONT_FOLLOW, IN_MASK_ADD, and IN_ONLYDIR were added in
>	version 2.5.)
>
>So that's almost 10 years.  In RHEL terms I think RHEL4 would be the
>latest without inotify support.
>
>OK, maybe that's long enough.

I should add that krb5 support was added on 13 January 2003,
(commit e0594725b51b5253237ed11b8bf3cf9ab87d9d48)
which corresponds to kernel version 2.5.57 or .58.

2.6.13 is from 29 August, 2005....so we'd kill support for that time
span...

>If there's an easy way to provide a fallback to dnotify, that would be
>nice

I think you and I have different ideas of the definition of the word
"nice" :)

>otherwise would you mind just adding a note about this somewhere?
>(Maybe the gssd man page should say something like "this version of gssd
>depends on inotify, introduced in kernel version 2.6.13...".)

I could add that in a separate patch...both to the changelog and the man
page. 


-- 
David H?rdeman