blktest failures

[Bob Pearson <rpearsonhpe@gmail.com>]

Bart,

I finally was able to build a kernel with lockdep enabled correctly and saw the error that you and others reported.
I am not familiar with lockdep output but I am guessing that it is reporting a mismatch between a _bh spinlock
and a _irqsave spinlock (since those are the only two types used by the driver.)

I went on campaign a while back to replace all the locks with _bh locks because I figured they would be
faster than _irqsave locks and because the driver never touched a lock except from a verbs API call or from
a tasklet (softirq.) As it turned out some code makes verbs API calls while in hardirq context which broke
that assumption. So some of the locks were reverted back to irqsave locks which fixed those warnings.

Now it is happening again. I did an experiment and went through the rxe driver and replaced all spinlocks
with _irqsave locks. Now the lockdep splats have gone away and the srp/001 test reports success. BUT,
it hangs and doesn't finish. If I try to run all the tests I get warnings about unable to remove the
scsi_debug driver. I am able to remove the rdma_rxe driver and reload it. I am not seeing any errors in
the rxe driver.

Do you have any ideas what to look at next?

Bob