Pull NFS client bugfixes from Trond Myklebust:
"Hightlights include:
- fix an rcu deadlock in nfs_delegation_find_inode()
- fix NFSv4 deadlocks due to not freeing the session slot in
layoutget
- don't send layoutreturn if the layout is already invalid
- prevent duplicate XID allocation
- flexfiles: Don't tie up all the rpciod threads in resends"
* tag 'nfs-for-4.18-2' of git://git.linux-nfs.org/projects/trondmy/linux-nfs:
pNFS/flexfiles: Process writeback resends from nfsiod context as well
pNFS/flexfiles: Don't tie up all the rpciod threads in resends
sunrpc: Prevent duplicate XID allocation
pNFS: Don't send layoutreturn if the layout is already invalid
pNFS: Always free the session slot on error in nfs4_layoutget_handle_exception
NFS: Fix an rcu deadlock in nfs_delegation_find_inode()
27db64f65f