This is a note to let you know that I've just added the patch titled

NFS: Fix a race between mmap() and O_DIRECT

to the 4.9-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git%3Ba=su...

The filename of the patch is: nfs-fix-a-race-between-mmap-and-o_direct.patch and it can be found in the queue-4.9 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let stable@vger.kernel.org know about it.

From e231c6879cfd44e4fffd384bb6dd7d313249a523 Mon Sep 17 00:00:00 2001

From: Trond Myklebust trond.myklebust@primarydata.com Date: Sun, 28 Jan 2018 09:29:41 -0500 Subject: NFS: Fix a race between mmap() and O_DIRECT

From: Trond Myklebust trond.myklebust@primarydata.com

commit e231c6879cfd44e4fffd384bb6dd7d313249a523 upstream.

When locking the file in order to do O_DIRECT on it, we must unmap any mmapped ranges on the pagecache so that we can flush out the dirty data.

Fixes: a5864c999de67 ("NFS: Do not serialise O_DIRECT reads and writes") Signed-off-by: Trond Myklebust trond.myklebust@primarydata.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org

--- fs/nfs/io.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/fs/nfs/io.c +++ b/fs/nfs/io.c @@ -98,7 +98,7 @@ static void nfs_block_buffered(struct nf { if (!test_bit(NFS_INO_ODIRECT, &nfsi->flags)) { set_bit(NFS_INO_ODIRECT, &nfsi->flags); - nfs_wb_all(inode); + nfs_sync_mapping(inode->i_mapping); } }

Patches currently in stable-queue which might be from trond.myklebust@primarydata.com are

queue-4.9/nfs-pnfs-fix-nfs_direct_req-ref-leak-when-i-o-falls-back-to-the-mds.patch queue-4.9/nfs-add-a-cond_resched-to-nfs_commit_release_pages.patch queue-4.9/nfs-commit-direct-writes-even-if-they-fail-partially.patch queue-4.9/nfs-fix-a-race-between-mmap-and-o_direct.patch