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Date: Wed, 28 Feb 2024 10:24:48 -0800
From: "Darrick J. Wong" <djwong@kernel.org>
To: Christoph Hellwig <hch@infradead.org>
Cc: linux-xfs@vger.kernel.org, hch@lst.de
Subject: Re: [PATCH 4/4] xfs: ask the dentry cache if it knows the parent of
 a directory
Message-ID: <20240228182448.GN1927156@frogsfrogsfrogs>
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 <170900014522.939516.4778985900477583664.stgit@frogsfrogsfrogs>
 <Zd9reRana7Fue2pN@infradead.org>
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On Wed, Feb 28, 2024 at 09:20:57AM -0800, Christoph Hellwig wrote:
> > +	parent = dget_parent(dentry);
> > +	if (!parent)
> > +		goto out_dput;
> > +
> > +	if (parent->d_sb != sc->ip->i_mount->m_super) {
> > +		dput(parent);
> > +		goto out_dput;
> > +	}
> 
> ->d_parent can't point to outside the current sb.

I know, I was being paranoid.  Granted if the dcache is broken then
there are probably bigger issues going on. :)

I'll change it to an ASSERT.

--D