1. 15 Dec, 2017 1 commit
    • Scott Mayhew's avatar
      nfs: fix a deadlock in nfs client initialization · c156618e
      Scott Mayhew authored
      The following deadlock can occur between a process waiting for a client
      to initialize in while walking the client list during nfsv4 server trunking
      detection and another process waiting for the nfs_clid_init_mutex so it
      can initialize that client:
      
      Process 1                               Process 2
      ---------                               ---------
      spin_lock(&nn->nfs_client_lock);
      list_add_tail(&CLIENTA->cl_share_link,
              &nn->nfs_client_list);
      spin_unlock(&nn->nfs_client_lock);
                                              spin_lock(&nn->nfs_client_lock);
                                              list_add_tail(&CLIENTB->cl_share_link,
                                                      &nn->nfs_client_list);
                                              spin_unlock(&nn->nfs_client_lock);
                                              mutex_lock(&nfs_clid_init_mutex);
                                              nfs41_walk_client_list(clp, result, cred);
                                              nfs_wait_client_init_complete(CLIENTA);
      (waiting for nfs_clid_init_mutex)
      
      Make sure nfs_match_client() only evaluates clients that have completed
      initialization in order to prevent that deadlock.
      
      This patch also fixes v4.0 trunking behavior by not marking the client
      NFS_CS_READY until the clientid has been confirmed.
      Signed-off-by: default avatarScott Mayhew <smayhew@redhat.com>
      Signed-off-by: default avatarAnna Schumaker <Anna.Schumaker@Netapp.com>
      c156618e
  2. 30 Nov, 2017 1 commit
  3. 29 Nov, 2017 2 commits
  4. 17 Nov, 2017 36 commits