From: Alexey Khoroshilov <redacted>
Date: Mon, 29 Jul 2013 06:58:08 +0400

ceph_build_auth() locks ac->mutex and then calls ceph_auth_build_hello()
that locks the same mutex, i.e. bring itself to deadlock.

The patch moves actual code from ceph_auth_build_hello() to
ceph_build_hello_auth_request() that should be called with ac->mutex held
and makes ceph_build_auth() calling it.
ceph_auth_build_hello() is left with untouched semantics as a wrapper
around ceph_build_hello_auth_request().

Found by Linux Driver Verification project (linuxtesting.org).

Signed-off-by: Alexey Khoroshilov <redacted>

I'm assume the ceph developers will pick this up, thanks.