[patch] mm: fix locking, inotify_read's ev_mutex vsdo_page_fault's mmap_sem...

[Ingo Molnar]

* Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> wrote:

> > [ 6460.634452] 
> > [ 6460.634465] =======================================================
> > [ 6460.634494] [ INFO: possible circular locking dependency detected ]
> > [ 6460.634517] 2.6.27-rc6-tip-00290-g8e229c3-dirty #1
> > [ 6460.634535] -------------------------------------------------------
> > [ 6460.634555] gdm-simple-gree/4778 is trying to acquire lock:
> > [ 6460.634574]  (&mm->mmap_sem){----}, at: [<c018fe33>] might_fault+0x36/0x73
> > [ 6460.634639] 
> > [ 6460.634645] but task is already holding lock:
> > [ 6460.634662]  (&dev->ev_mutex){--..}, at: [<c01c7a76>] inotify_read+0xd8/0x16e
> > [ 6460.634715] 
> > [ 6460.634721] which lock already depends on the new lock.
> 
> Yes, there's a thread in my intray called "inotify_read's ev_mutex vs 
> do_page_fault's mmap_sem...".  It's a bit flakey-looking, but there's 
> a patch in there.

ah, thx. I picked up the patch into tip/out-of-tree. (see below for a 
tided up changelog) Please queue it up as v2.6.27 material. (i'll report 
it if anything breaks due to the patch)

	Ingo

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