Kernel hangs on reboot on system with 05/2013~06/2013 CURRENT sources

[Garrett Cooper]

    Long story short is that I've run into an issue on several VM
images and real machines where UFS on mpt fails to reboot because it
hangs in the kernel. I don't have any specific details, other than it
occurs regularly with cam/mpt on VMware boxes running builds; however
I've also seen this occur with a Dell box that has an mpt SAS
controller with 2 zpools and gobs of RAM. Does anyone know of any
issues in this area [recently]?
    This set of issues appears to have started cropping up after
03/2013, because I was running reliable builds off those sources.
Thanks!
-Garrett

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