On Nov 25, 2013, at 12:57, <andros@xxxxxxxxxx> <andros@xxxxxxxxxx> wrote: > From: Andy Adamson <andros@xxxxxxxxxx> > > The state manager is recovering expired state and recovery OPENs are being > processed. If kswapd is pruning inodes at the same time, a deadlock can occur > when kswapd calls evict_inode on an NFSv4.1 inode with a layout, and the > resultant layoutreturn gets an error that the state mangager is to handle, > causing the layoutreturn to wait on the (NFS client) cl_rpcwaitq. > > At the same time an open is waiting for the inode deletion to complete in > __wait_on_freeing_inode. > > If the open is either the open called by the state manager, or an open from > the same open owner that is holding the NFSv4.0 sequence id which causes the > OPEN from the state manager to wait for the sequence id on the Seqid_waitqueue, > then the state is deadlocked with kswapd. > > Do not handle LAYOUTRETURN errors when called from nfs4_evict_inode. Why are we waiting for recovery in LAYOUTRETURN at all? Layouts are automatically lost when the server reboots or when the lease is otherwise lost. IOW: Is there any reason why we need to special-case nfs4_evict_inode? Shouldn’t we just bail out on error in _all_ cases? Cheers Trond -- Trond Myklebust Linux NFS client maintainer NetApp Trond.Myklebust@xxxxxxxxxx www.netapp.com -- To unsubscribe from this list: send the line "unsubscribe linux-nfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
