[  452.744045] Freezing of tasks failed after 20.01 seconds (1 tasks refusing to freeze, wq_busy=0):
[  452.744187] plasma-desktop  D f30c7d20     0  1531      1 0x00800004
[  452.744194]  f30c7d68 00200086 c189fd00 f30c7d20 0000b9c0 00200296 c175dfe0 c1868ec0
[  452.744201]  c1868ec0 201e4a2d 00000064 f5805ec0 f30c8000 f26abfc0 00200246 f30c7d24
[  452.744209]  c152c5b6 f30c7d48 00200246 f30c7d34 c152c5b6 f30c7d50 f8106ee8 f30c7d44
[  452.744216] Call Trace:
[  452.744230]  [<c152c5b6>] ? _raw_spin_unlock_bh+0x16/0x20
[  452.744235]  [<c152c5b6>] ? _raw_spin_unlock_bh+0x16/0x20
[  452.744271]  [<f8106ee8>] ? rpc_wake_up_next+0x48/0x90 [sunrpc]
[  452.744278]  [<c1026018>] ? default_spin_lock_flags+0x8/0x10
[  452.744282]  [<c152c6ed>] ? _raw_spin_lock_irqsave+0x2d/0x40
[  452.744298]  [<f810678e>] rpc_wait_bit_killable+0x1e/0x40 [sunrpc]
[  452.744303]  [<c152b1ef>] __wait_on_bit+0x4f/0x70
[  452.744318]  [<f8106770>] ? rpc_release_task+0xb0/0xb0 [sunrpc]
[  452.744333]  [<f8106770>] ? rpc_release_task+0xb0/0xb0 [sunrpc]
[  452.744337]  [<c152b271>] out_of_line_wait_on_bit+0x61/0x70
[  452.744344]  [<c10662a0>] ? autoremove_wake_function+0x50/0x50                                                                                                                  
[  452.744359]  [<f8107163>] __rpc_execute+0xe3/0x1b0 [sunrpc]                                                                                                                     
[  452.744375]  [<f8107368>] rpc_execute+0x38/0x40 [sunrpc]                                                                                                                        
[  452.744388]  [<f8100439>] rpc_run_task+0x59/0x70 [sunrpc]                                                                                                                       
[  452.744402]  [<f810054c>] rpc_call_sync+0x3c/0x60 [sunrpc]                                                                                                                      
[  452.744433]  [<f82b3e43>] _nfs4_call_sync+0x23/0x30 [nfs]                                                                                                                       
[  452.744453]  [<f82b305e>] _nfs4_proc_getattr+0x8e/0xa0 [nfs]                                                                                                                    
[  452.744474]  [<f82b489b>] nfs4_proc_getattr+0x3b/0x60 [nfs]                                                                                                                     
[  452.744491]  [<f829f62a>] __nfs_revalidate_inode+0x7a/0x1f0 [nfs]                                                                                                               
[  452.744507]  [<f829f83f>] nfs_revalidate_inode+0x2f/0x50 [nfs]                                                                                                                  
[  452.744522]  [<f829f8fc>] nfs_getattr+0x4c/0x100 [nfs]                                                                                                                          
[  452.744527]  [<c112c5b2>] vfs_getattr+0x42/0x70                                                                                                                                 
[  452.744542]  [<f829f8b0>] ? nfs_close_context+0x50/0x50 [nfs]                                                                                                                   
[  452.744546]  [<c112c647>] vfs_fstatat+0x67/0x80                                                                                                                                 
[  452.744550]  [<c112c6b0>] vfs_stat+0x20/0x30                                                                                                                                    
[  452.744554]  [<c112c916>] sys_stat64+0x16/0x30                                                                                                                                  
[  452.744558]  [<c152c8d4>] syscall_call+0x7/0xb                                                                                                                                  
[  452.744565]  [<c1520000>] ? reserve_backup_gdb.isra.11+0x285/0x2c0