I added the tracefs functionality to wrapfs. wrapfs is a stackable file system that intercepts file system calls and Tracefs basically records the VFS calls into a file on disk. wrapfs worked fine its that when I added the logging functionality it failed. The issue I am having is that When I run a workload on the mounted file system (wrapfs+tracefs) the system freezes. the mouse pointer does not even move. I set it up in virtual box and had the kernel dump the messages to a serial port which I then read from my host OS. I did this following the instructions on this page: http://linuxdeveloper.blogspot.com/2012/05/debugging-linux-kernel-over-seria... When the guest OS freezes I get the following messages seen below. I would like to know what is a good approach for debugging this issue. I am not sure what a process stall is. Is that a deadlock? [ 780.357876] BUG: soft lockup - CPU#0 stuck for 22s! [nautilus:1382] [ 780.361658] Process nautilus (pid: 1382, ti=dca12000 task=dc837230 task.ti=d) [ 780.361658] Stack: [ 780.361658] Call Trace: [ 780.361658] Code: 90 b8 43 64 03 c1 b9 40 64 03 c1 e9 49 ff ff ff 90 55 ba 0 [ 808.356372] BUG: soft lockup - CPU#0 stuck for 22s! [nautilus:1382] [ 808.360223] Process nautilus (pid: 1382, ti=dca12000 task=dc837230 task.ti=d) [ 808.360223] Stack: [ 808.360223] Call Trace: [ 808.360223] Code: ff ff 90 b8 43 64 03 c1 b9 40 64 03 c1 e9 49 ff ff ff 90 5 [ 814.876223] INFO: rcu_sched detected stall on CPU 0 (t=15000 jiffies) [ 814.876223] Process nautilus (pid: 1382, ti=dca12000 task=dc837230 task.ti=d) [ 814.876223] Stack: [ 814.876223] Call Trace: [ 814.876223] Code: 00 c3 ff ff 80 e5 10 75 ee c1 e6 18 89 b0 10 c3 ff ff 89 d Thanks. Salam