when a mounted remote smb server goes down - cifs vfs tries to re-connect - with strange side-effects

Hi Jeff, Steve, ...

I'm running here on opensuse 11.2 - tried default kernel - and now 2.6.33-rc2-0.1-default from latest cifs git.

When mounting a remote smb server - and then that server goes down (just shutdown, no network cable unplugged),
my client KDE4.x desktop becomes _very_ unresponsive - the (kicker) taskbar is now _unusable_ - no response
at all - which also means that a user can't even use the GUI to shutdown.

As soon i restart the remote smb server, all is fine again.

Used many tools (like those from sysstat) - but at least CPU usage seem to be  _not_ the problem.

Could it be some kernel semaphores....?

When the remote server is down, wireshark only shows some 3 seconds tcp/ip traffic on ports 139 and 445.

From the cifs (debug 7) kernel log:

Jan  5 04:38:01 linux300 kernel: [46253.309431]  fs/cifs/inode.c: Getting info on //linux700/homegk                                     
Jan  5 04:38:01 linux300 kernel: [46253.309438]  fs/cifs/cifssmb.c: In QPathInfo (Unix) the path //linux700/homegk                      
Jan  5 04:38:04 linux300 kernel: [46256.080085]  fs/cifs/connect.c: Socket created                                                      
Jan  5 04:38:04 linux300 kernel: [46256.080740]  fs/cifs/connect.c: Error -111 connecting to server via ipv4                            
Jan  5 04:38:04 linux300 kernel: [46256.080770]  fs/cifs/connect.c: reconnect error -111                                                
Jan  5 04:38:07 linux300 kernel: [46259.084106]  fs/cifs/connect.c: Socket created                                                      
Jan  5 04:38:07 linux300 kernel: [46259.084773]  fs/cifs/connect.c: Error -111 connecting to server via ipv4                            
Jan  5 04:38:07 linux300 kernel: [46259.084804]  fs/cifs/connect.c: reconnect error -111                                                
Jan  5 04:38:10 linux300 kernel: [46262.088085]  fs/cifs/connect.c: Socket created                                                      
Jan  5 04:38:10 linux300 kernel: [46262.088728]  fs/cifs/connect.c: Error -111 connecting to server via ipv4                            
Jan  5 04:38:10 linux300 kernel: [46262.088758]  fs/cifs/connect.c: reconnect error -111                                                
Jan  5 04:38:11 linux300 kernel: [46263.308062]  fs/cifs/cifssmb.c: gave up waiting on reconnect in smb_init                            
Jan  5 04:38:11 linux300 kernel: [46263.308082]  fs/cifs/inode.c: error on getting revalidate info -112                                 
Jan  5 04:38:11 linux300 kernel: [46263.308090]  fs/cifs/inode.c: cifs_revalidate - inode unchanged                                     
Jan  5 04:38:11 linux300 kernel: [46263.308102]  fs/cifs/inode.c: CIFS VFS: leaving cifs_revalidate (xid = 224) rc = 
-112               
Jan  5 04:38:11 linux300 kernel: [46263.310204]  fs/cifs/inode.c: CIFS VFS: in cifs_revalidate as Xid: 225 with uid: 
1000               
Jan  5 04:38:11 linux300 kernel: [46263.310226]  fs/cifs/inode.c: Revalidate: //linux700/homegk inode 0xf41c3e84 count 1 
dentry: 0xdaa7325c d_time 1951477551 jiffies 11490827                                                                                                  
Jan  5 04:38:11 linux300 kernel: [46263.310236]  fs/cifs/inode.c: Getting info on //linux700/homegk                                     
Jan  5 04:38:11 linux300 kernel: [46263.310243]  fs/cifs/cifssmb.c: In QPathInfo (Unix) the path //linux700/homegk                      
Jan  5 04:38:13 linux300 kernel: [46265.092103]  fs/cifs/connect.c: Socket created                                                      
Jan  5 04:38:13 linux300 kernel: [46265.092744]  fs/cifs/connect.c: Error -111 connecting to server via ipv4                            
Jan  5 04:38:13 linux300 kernel: [46265.092774]  fs/cifs/connect.c: reconnect error -111                                                
Jan  5 04:38:16 linux300 kernel: [46268.096101]  fs/cifs/connect.c: Socket created                                                      
Jan  5 04:38:16 linux300 kernel: [46268.096751]  fs/cifs/connect.c: Error -111 connecting to server via ipv4                            
Jan  5 04:38:16 linux300 kernel: [46268.096781]  fs/cifs/connect.c: reconnect error -111                                                
Jan  5 04:38:19 linux300 kernel: [46271.100088]  fs/cifs/connect.c: Socket created                                                      
Jan  5 04:38:19 linux300 kernel: [46271.100729]  fs/cifs/connect.c: Error -111 connecting to server via ipv4                            
Jan  5 04:38:19 linux300 kernel: [46271.100758]  fs/cifs/connect.c: reconnect error -111                                                
Jan  5 04:38:21 linux300 kernel: [46273.308054]  fs/cifs/cifssmb.c: gave up waiting on reconnect in smb_init                            
Jan  5 04:38:21 linux300 kernel: [46273.308075]  fs/cifs/inode.c: error on getting revalidate info -112                                 
Jan  5 04:38:21 linux300 kernel: [46273.308083]  fs/cifs/inode.c: cifs_revalidate - inode unchanged                                     
Jan  5 04:38:21 linux300 kernel: [46273.308097]  fs/cifs/inode.c: CIFS VFS: leaving cifs_revalidate (xid = 225) rc = 
-112               
Jan  5 04:38:21 linux300 kernel: [46273.311877]  fs/cifs/inode.c: CIFS VFS: in cifs_revalidate as Xid: 226 with uid: 
1000               
Jan  5 04:38:21 linux300 kernel: [46273.311901]  fs/cifs/inode.c: Revalidate: //linux700/homegk inode 0xf41c3e84 count 1 
dentry: 0xdaa7325c d_time 1951477551 jiffies 11493327                                                                                                  
Jan  5 04:38:21 linux300 kernel: [46273.311912]  fs/cifs/inode.c: Getting info on //linux700/homegk 


Cheers, Günter