spin_lock on SCSI

[goetz at net-amp.com]

Hi Matt,

I have applied the patch
DragonFly x17.net.intra 2.8-RELEASE DragonFly v2.8.2.16.gfc7bf0-RELEASE 
#3: Sat Nov  6 13:31:53 CET 2010     
root at x17.net.intra:/usr/obj/usr/src/sys/XEON  i386

tested "hammering" the ufs -
and so far your patch solved the problem, great!
Regards Goetz

Matthew Dillon schrieb:
:Hi,
:backtrace available at
:http://www.net-amp.com/test/dump/
:backtrace above is from fresh install with 2.8.2 CD SMP
:...
:happens when starting heavy IO - in this case git pull :-(
    Excellent, that backtrace was very useful.

    Here is an untested kernel source patch for you to try.  You do need
    to compile up a kernel to test this.  A spinlock was being held
    through a softupdates callback.  The problem only occurs when running
    on UFS (and since most of us run on HAMMER we didn't notice).
    fetch http://apollo.backplane.com/DFlyMisc/vfs01.patch

						-Matt