From mboxrd@z Thu Jan  1 00:00:00 1970
From: Al Viro <viro@ZenIV.linux.org.uk>
Subject: Re: dcache shrink list corruption?
Date: Fri, 2 May 2014 23:40:22 +0100
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Cc: Miklos Szeredi <miklos@szeredi.hu>,
	Dave Chinner <david@fromorbit.com>,
	Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
	linux-fsdevel <linux-fsdevel@vger.kernel.org>
To: Linus Torvalds <torvalds@linux-foundation.org>
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On Fri, May 02, 2014 at 02:18:43PM -0700, Linus Torvalds wrote:
> On Fri, May 2, 2014 at 2:08 PM, Miklos Szeredi <miklos@szeredi.hu> wrote:
> > There's more of the "delete from shrink list not owned by us" in select parent.
> > Proposed patch appended.
> 
> Ahh. Clearly this needs more work before I pull.

*nod*

Besides, I want to put Miklos' "don't bother with RCU in shrink_dentry_list()"
in there as soon as select_collect() has been dealt with.  I don't think
that the currently posted patch for select_collect() is right, though -
see my reply to parent posting.  Basically, I think we should treat "it's
on the shrink list already" as "increment data->found and keep going".  IOW,
	if (on shrink list) {
		data->found++;
	} else {
		if (on lru list)
			d_lru_del
		if (refcount is zero) {
			d_shrink_add
			data->found++;
		}
	}
	if (data->found)
		ret = need_resched() ? D_WALK_QUIT : D_WALK_NORETRY;