lkml.org 
[lkml]   [2017]   [Jan]   [18]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 4.4 38/48] pNFS: Fix race in pnfs_wait_on_layoutreturn
Date
4.4-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Trond Myklebust <trond.myklebust@primarydata.com>

commit ee284e35d8c71bf5d4d807eaff6f67a17134b359 upstream.

We must put the task to sleep while holding the inode->i_lock in order
to ensure atomicity with the test for NFS_LAYOUT_RETURN.

Fixes: 500d701f336b ("NFS41: make close wait for layoutreturn")
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
fs/nfs/pnfs.c | 8 +++-----
1 file changed, 3 insertions(+), 5 deletions(-)

--- a/fs/nfs/pnfs.c
+++ b/fs/nfs/pnfs.c
@@ -1185,13 +1185,11 @@ bool pnfs_wait_on_layoutreturn(struct in
* i_lock */
spin_lock(&ino->i_lock);
lo = nfsi->layout;
- if (lo && test_bit(NFS_LAYOUT_RETURN, &lo->plh_flags))
+ if (lo && test_bit(NFS_LAYOUT_RETURN, &lo->plh_flags)) {
+ rpc_sleep_on(&NFS_SERVER(ino)->roc_rpcwaitq, task, NULL);
sleep = true;
+ }
spin_unlock(&ino->i_lock);
-
- if (sleep)
- rpc_sleep_on(&NFS_SERVER(ino)->roc_rpcwaitq, task, NULL);
-
return sleep;
}


\
 
 \ /
  Last update: 2017-01-18 11:52    [W:0.958 / U:0.332 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site