From 3b1ea43009f2aca9f8ff0dd6540f6701e0871baf Mon Sep 17 00:00:00 2001 From: Devesh Sharma Date: Thu, 24 Dec 2015 13:14:07 -0500 Subject: RDMA/ocrdma: Depend on async link events from CNA Recently Dough Ledford reported a deadlock happening between ocrdma-load sequence and NetworkManager service issuing "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. With this patch we stop using administrative open and close events injected by be2net driver. These events were used to dispatch PORT_ACTIVE and PORT_ERROR events to the IB-stack. This patch implements a logic to receive async-link-events generated from CNA whenever link-state-change is detected. Now on, these async-events will be used to dispatch PORT_ACTIVE and PORT_ERROR events to IB-stack. Depending on async-events from CNA removes the need to hold device-list-mutex and thus breaks the busy-wait scenario. Reported-by: Doug Ledford CC: Sathya Perla Signed-off-by: Padmanabh Ratnakar Signed-off-by: Selvin Xavier Signed-off-by: Devesh Sharma Signed-off-by: Doug Ledford --- drivers/infiniband/hw/ocrdma/ocrdma_verbs.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers/infiniband/hw/ocrdma/ocrdma_verbs.c') diff --git a/drivers/infiniband/hw/ocrdma/ocrdma_verbs.c b/drivers/infiniband/hw/ocrdma/ocrdma_verbs.c index 7bd99d5..d4c687b 100644 --- a/drivers/infiniband/hw/ocrdma/ocrdma_verbs.c +++ b/drivers/infiniband/hw/ocrdma/ocrdma_verbs.c @@ -171,7 +171,7 @@ static inline void get_link_speed_and_width(struct ocrdma_dev *dev, int status; u8 speed; - status = ocrdma_mbx_get_link_speed(dev, &speed); + status = ocrdma_mbx_get_link_speed(dev, &speed, NULL); if (status) speed = OCRDMA_PHYS_LINK_SPEED_ZERO; -- cgit v1.1