Bug 16033

Summary: xfs lockup preallocating files (first hang notice: xfsconvertd)
Product: File System Reporter: bugzillakernelorg
Component: XFSAssignee: Dave Chinner (david)
Status: RESOLVED INSUFFICIENT_DATA    
Severity: normal CC: alan, david
Priority: P1    
Hardware: All   
OS: Linux   
Kernel Version: 2.6.32-22-generic (ubuntu) Subsystem:
Regression: No Bisected commit-id:

Description bugzillakernelorg 2010-05-23 05:48:32 UTC 
xfs deadlocks when preallocating files; say, from transmission starting a torrent; the "hung task" notifier first mentions xfsconvertd, then all that follows trying to write or sync the disk. i'm filing this bug as a placeholder for the moment as i didn't collect the kernel messages last time it occurred, but i plan on doing so as soon as possible.
Comment 1 Dave Chinner 2010-05-24 00:34:08 UTC 
Fixed upstream in commit:

c626d174cfe38e7f0545d074c299527892cd8c45 xfs: prevent unwritten extent conversion from blocking I/O completion
Comment 2 Dave Chinner 2010-05-24 00:38:39 UTC 
oops, sorry, might have pulled the trigger to quickly. That's the commit that introduces xfsconvertd (I should look at the diffs first :/).

Make sure you get the output of 'echo w > /proc/sysrq-trigger' when it next hangs...