2.4.20: Proccess stuck in __lock_page ...

[manish]

Hello !

I am running the 2.4.20 kernel on a system with 3.5 GB RAM and dual CPU. 
I am running bonnie accross four drives in parallel:

bonnie -s 1000 -d /<dir-name>

bdflush settings on this system:

[root@dyn-10-123-130-235 vm]# cat bdflush
2       50      32      100     50      300     1       0       0

All the bonnie process and any other process (like df, ps -ef etc.) are 
hung in __lock_page. Breaking into kdb, I observe the following for one 
such bonnie process:

schedule(..)
__lock_page(..)
lock_page(..)
do_generic_file_read(..)
generic_file_read(..)

After this, the processes never exit the hang. At times, a couple of 
bonnie processes complete but the hang still occurs with the remaining 
processes and with the other processes.

I tried out the 2.5.33 kernel (one of the 2.5 series) and observed that 
the hang does not occur. If I run, two bonnie processes, they never get 
stuck. Actually, if I run 4 parallel mke2fs, they too get stuck.

Any clues where this could be happening?

Thanks
-Manish