RDMA/be2net: Remove open and close entry points
Recently Dough Ledford reported a deadlock happening between ocrdma-load sequence and NetworkManager service issueing "open" on be2net interface. The deadlock happens when any be2net hook (e.g. open/close) is called in parallel to insmod ocrdma.ko. A. be2net is sending administrative open/close event to ocrdma holding device_list_mutex. It does this from ndo_open/ndo_stop hooks of be2net. So sequence of locks is rtnl_lock---> device_list lock B. When new ocrdma roce device gets registered, infiniband stack now takes rtnl_lock in ib_register_device() in GID initialization routines. So sequence of locks in this path is device_list lock ---> rtnl_lock. This improper locking sequence causes deadlock. In order to resolve the above deadlock condition, ocrdma intorduced a patch to stop listening to administrative open/close events generated from be2net driver. It now depends on link-state-change async-event generated from CNA. This change leaves behind dead code which used to generate administrative open/close events. This patch cleans-up all that dead code from be2net. Reported-by: Doug Ledford <dledford@redhat.com> CC: Sathya Perla <sathya.perla@avagotech.com> Signed-off-by: Padmanabh Ratnakar <padmanabh.ratnakar@avagotech.com> Signed-off-by: Selvin Xavier <selvin.xavier@avagotech.com> Signed-off-by: Devesh Sharma <devesh.sharma@avagotech.com> Signed-off-by: Doug Ledford <dledford@redhat.com>
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