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From: "Rafael J. Wysocki" <rjw@sisk.pl>
To: Matthew Garrett <mjg59@srcf.ucam.org>
Subject: Re: removing refrigerator does not help with s2ram vs. fuse deadlocks (was Re: [linux-pm] Re: [PATCH] Remove process freezer from suspend to RAM pathway)
Date: Thu, 5 Jul 2007 16:28:11 +0200
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Cc: Pavel Machek <pavel@ucw.cz>, Paul Mackerras <paulus@samba.org>,
       Alan Stern <stern@rowland.harvard.edu>,
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On Thursday, 5 July 2007 15:57, Matthew Garrett wrote:
> On Thu, Jul 05, 2007 at 11:15:26AM +0200, Pavel Machek wrote:
> 
> > Now, if kernel needs FUSE services for some reason (that's the problem
> > we hit in s2ram case, right?), we have a deadlock.
> > 
> > So main problem still seems to be "kernel should not depend on
> > userland services during suspend", refrigerator or not.
> 
> And also "Userland should not depend on userland services", which is 
> rather more of a problem.

I think you're oversimplifying it, as far as FUSE is concerned.

Namely, if there are two userland tasks, A and B, and B is uninterruptible,
because A is blocked, then this is not a usual situation.

Greetings,
Rafael


-- 
"Premature optimization is the root of all evil." - Donald Knuth