5.4-RC2 freezing - ATA related?

[Peter Jeremy]

On Wed, 2005-May-18 06:43:37 -0600, Elliot Finley wrote:
>Had the system lock up again.  This is with the new ATA mkIII patches on
>http://people.freebsd.org/~sos/ATA.
>
>I didn't get the crashdump (forgot to set dumpdev), but I did get 'ps' and
>'show lockedvnods' output from DDB.  The output is in the form of
>screenshots combined into a single .pdf which can be accessed here
>http://www.efinley.com/Binder1.pdf

That shows a deadlock-to-root in your /dev/ar0s1a (presumably root)
filesystem.  The perl process (pid 487) has an exclusive lock on
the FS mountpoint - this is blocking 130 other processes.  Pid 487
is itself waiting on another filesystem lock (you can't determine
the actual lock tree without more poking around kernel memory).

The vnode locks are held by processes:
 PID   name        waiting on
 487  perl       [ufs c3c1c1b4]
  57  syncer     [snaplk c535f500]  (holds 2 locks)
 476  perl       [ufs c87e4f1c]
 489  perl       [snaplk c535f500]  (holds 2 locks)
3337  mksnap_ffs [getblk d77656f4]

Looking through the process list, cron has started a "dump -L" which
is trying to create a filesystem snapshot.  That has wedged on
"getblk" (trying to perform physical disk I/O) and is probably the
root of your problem.  Nothing else is waiting on physical I/O.

I'd say that your first guess was right:  This is a bug in the ATA
code and is probably a job for sos.

-- 
Peter Jeremy