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From: Trond Myklebust <Trond.Myklebust@netapp.com>
To: Jim Rees <rees@umich.edu>
Cc: John Hughes <john@Calva.COM>, Jeff Layton <jlayton@redhat.com>,
	linux-nfs@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] Don't hang user processes if Kerberos ticket for nfs4 mount expires
Date: Fri, 18 Nov 2011 20:23:44 +0200	[thread overview]
Message-ID: <1321640624.2653.5.camel@lade.trondhjem.org> (raw)
In-Reply-To: <20111118175409.GA1347@umich.edu>

On Fri, 2011-11-18 at 12:54 -0500, Jim Rees wrote: 
> Myklebust, Trond wrote:
> 
>   So what are they supposed to do without tickets? Crash?
> 
> No, why would they want to do that?
> 
> I feel like I've entered the Twilight Zone here, so please continue without
> me while I dig up the relevant background info.

The point is that if the server won't allow them to issue read or write
system calls, then there are 2 options available to them: 

     1. hang until someone renews their ticket 
     2. get an error which means crash, since most (all?) applications
        aren't written according to the non-posix assumption that read
        and write can return EACCES/EKEYEXPIRED errors.



Trond

-- 
Trond Myklebust
Linux NFS client maintainer

NetApp
Trond.Myklebust@netapp.com
www.netapp.com


  reply	other threads:[~2011-11-18 18:23 UTC|newest]

Thread overview: 16+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2011-11-18 17:16 [PATCH] Don't hang user processes if Kerberos ticket for nfs4 mount expires Myklebust, Trond
2011-11-18 17:54 ` Jim Rees
2011-11-18 18:23   ` Trond Myklebust [this message]
  -- strict thread matches above, loose matches on Subject: below --
2011-11-16 18:14 John Hughes
2011-11-16 19:47 ` Jeff Layton
2011-11-16 23:44   ` Jim Rees
2011-11-17  1:31     ` Jeff Layton
2011-11-17  1:38       ` Jeff Layton
2011-11-17 11:05         ` John Hughes
2011-11-17 13:13           ` John Hughes
2011-11-17 21:46             ` Jeff Layton
2011-11-18  1:51               ` Jim Rees
2011-11-18  2:03                 ` Jeff Layton
     [not found]               ` <4EC62325.1060009@Calva.COM>
2011-11-18 12:50                 ` Jim Rees
2011-11-17  1:46       ` Matt W. Benjamin
2011-11-17  9:37   ` John Hughes

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