tree efd81d0f35e2300ee86e538fa8c136654c7c0dae
parent da7de31cc50796a53593785d4508b7b7ffa9a9b2
author Ursula Braun <braunu@de.ibm.com> 1184465021 -0700
committer David S. Miller <davem@davemloft.net> 1184465021 -0700

[AF_IUCV]: Avoid deadlock between iucv_path_connect and tasklet.

An iucv deadlock may occur, where one CPU is spinning on the
iucv_table_lock for iucv_tasklet_fn(), while another CPU is holding
the iucv_table_lock for an iucv_path_connect() and is waiting for
the first CPU in an smp_call_function.
Solution: replace spin_lock in iucv_tasklet_fn by spin_trylock and
reschedule tasklet in case of non-granted lock.

Signed-off-by: Ursula Braun <braunu@de.ibm.com>
Acked-by: Frank Pavlic <fpavlic@de.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>