kern/134584: [panic] spin lock held too long

[Attilio Rao]

The following reply was made to PR kern/134584; it has been noted by GNATS.

From: Attilio Rao <attilio at freebsd.org>
To: barbara <barbara.xxx1975 at libero.it>
Cc: bug-followup <bug-followup at freebsd.org>, FreeBSD-stable <FreeBSD-stable at freebsd.org>
Subject: Re: kern/134584: [panic] spin lock held too long
Date: Sun, 26 Jul 2009 16:36:44 +0200

 2009/7/26 barbara <barbara.xxx1975 at libero.it>:
 > It happened again, on shutdown.
 > As the previous time, it happened after a high (for a desktop) uptime and, if it could matter, after running net-p2p/transmission-gtk2 for several hours.
 > I don't know if it's related, but often quitting transmission, doesn't terminate the process. Sometimes it end after several minutes the gui exited, sometimes it's still running after hours.
 > I've noticed it as the destination folder is on a manually mounted device and I can't umount it as fstat reports the device used by a transmission process.
 > So I often have to kill it.
 > This happened both the time I had this kind of panic.
 
 Can you try to reproduce it with WITNESS and *without*
 WITNESS_SKIPSPIN? I would need to look at "show alllocks" and
 possibily "ps" because it seems that the lock owner is preempted but
 it should not happen while holding a spinlock (unless the acquired
 spinlock is the one in the preempting path, in this case thought it
 should drop inside sched_switch() and we can try to understand why
 that doesn't happen).
 
 Thanks,
 Attilio
 
 
 -- 
 Peace can only be achieved by understanding - A. Einstein