panic: sched_priority: invalid priority 3990 on r225375

John Baldwin jhb at
Wed Sep 7 17:43:21 UTC 2011

On Sunday, September 04, 2011 7:21:23 pm Ryan Stone wrote:
> I've gotten the following panic twice while running recent builds of
> head under VirtualBox(FreeBSD 8.2 host).
> panic: sched_priority: invalid priority 3990: nice 0, ticks 1227873280
> ftick 175669871 ltick 175679894 tick pri 3818
> The crashes happened while I was running a stress test of the network
> stack.  I have a client machine and a server machine.  The client is
> running head with a patch that I'm trying to prove out; the server
> should be running with basically stock head as of r225375(I think that
> there's a couple of minor changes in the tree I used to build the
> server with, but I've gotten the crash on the client and the server,
> and neither have any uncommitted patches in common).  The server is
> running several netcat instances in listen mode; the client has a
> script sitting in a loop starting netcat instances that connect to
> instances running on the server and send data from client -> server.
> The client also has a script that changes the routing tables
> periodically.
> Both the client and the server have crashed once so far.  I haven't
> been running any tests on actual hardware so I can't say whether this
> is a FreeBSD problem or a VirtualBox problem.  I'm going to start
> running the same tests against VMs running some version of FreeBSD 8
> to see if I can reproduce the problem there.  In the meantime, I've
> made a core.txt accessible in case anybody wants to take a look.  You
> can find it at:
> Please let me know if you need any more information.

This is due to ts->ts_ticks being way too large.  I think it needs a cap to 
handle this case, but I'm not sure exactly which bits need to be capped, and 
what the maximum value they should be capped at is.

John Baldwin

More information about the freebsd-current mailing list