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Subject: Re: [PATCH v2] NFS41: make close wait for layoutreturn
To: Trond Myklebust <trond.myklebust@primarydata.com>
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Cc: Peng Tao <tao.peng@primarydata.com>,
        Linux NFS Mailing List <linux-nfs@vger.kernel.org>,
        kinglongmee@gmail.com
From: Kinglong Mee <kinglongmee@gmail.com>
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Date: Wed, 23 Sep 2015 20:45:41 +0800
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On 9/23/2015 20:05, Trond Myklebust wrote:
> On Wed, Sep 23, 2015 at 4:27 AM, Kinglong Mee <kinglongmee@gmail.com> wrote:
>> I find the inode returned from nfs_igrab_and_active is NULL
>> in _nfs4_proc_delegreturn(),
>>
>>         data->inode = nfs_igrab_and_active(inode);
>>
>> So that, NFS_I(inode) causes the panic.
> 
> I've added a check for ino == NULL to nfs4_wait_on_layoutreturn()...

Yes, that's right.

But you add the checking at the wrong place in pnfs_wait_on_layoutreturn() at your tree.


+bool pnfs_wait_on_layoutreturn(struct inode *ino, struct rpc_task *task)
+{
+        struct pnfs_layout_hdr *lo;
+        bool sleep = false;
+
+	if (ino == NULL)
+		goto out;
+	/* we might not have grabbed lo reference. so need to check under

thanks, 
Kinglong Mee