From mboxrd@z Thu Jan  1 00:00:00 1970
From: Al Viro <viro@ZenIV.linux.org.uk>
Subject: Re: fs/dcache.c - BUG: soft lockup - CPU#5 stuck for 22s!
 [systemd-udevd:1667]
Date: Thu, 29 May 2014 14:30:36 +0100
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Cc: Linus Torvalds <torvalds@linux-foundation.org>,
	Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
	Miklos Szeredi <mszeredi@suse.cz>,
	linux-fsdevel <linux-fsdevel@vger.kernel.org>
To: Mika Westerberg <mika.westerberg@linux.intel.com>
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On Thu, May 29, 2014 at 02:04:39PM +0300, Mika Westerberg wrote:

> With your both patches applied the problem is gone :-)
> 
> I did 20 plug/unplugs, rebooted the machine and another 20 plug/unplugs
> and didn't see the livelock at once.

Great...  OK, saner splitup of that sucker (equivalent to combination of
these two patches) is in vfs.git#for-linus.

Review and testing would be very welcome.

PS: The diff between that and aforementioned "both patches applied" is noise -
dentry and parent declarations had been moved into the loop body there,
while in #for-linus they are left alone.  So Mika's testing results should
apply to that one as well.