IB/hfi1: Harden state transition to Armed and Active
There is a window that allows other threads to read state of
'host_link_state' as a new, before the hardware actual state is set.
This patch closes the window by indicating a new state only after
hardware transition is complete.
Reviewed-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Alex Estrin <alex.estrin@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
diff --git a/drivers/infiniband/hw/hfi1/chip.c b/drivers/infiniband/hw/hfi1/chip.c
index 8f7ce74..eca31dd 100644
--- a/drivers/infiniband/hw/hfi1/chip.c
+++ b/drivers/infiniband/hw/hfi1/chip.c
@@ -10602,16 +10602,15 @@ int set_link_state(struct hfi1_pportdata *ppd, u32 state)
break;
}
- ppd->host_link_state = HLS_UP_ARMED;
set_logical_state(dd, LSTATE_ARMED);
ret = wait_logical_linkstate(ppd, IB_PORT_ARMED, 1000);
if (ret) {
- /* logical state didn't change, stay at init */
- ppd->host_link_state = HLS_UP_INIT;
dd_dev_err(dd,
"%s: logical state did not change to ARMED\n",
__func__);
+ break;
}
+ ppd->host_link_state = HLS_UP_ARMED;
/*
* The simulator does not currently implement SMA messages,
* so neighbor_normal is not set. Set it here when we first
@@ -10624,18 +10623,16 @@ int set_link_state(struct hfi1_pportdata *ppd, u32 state)
if (ppd->host_link_state != HLS_UP_ARMED)
goto unexpected;
- ppd->host_link_state = HLS_UP_ACTIVE;
set_logical_state(dd, LSTATE_ACTIVE);
ret = wait_logical_linkstate(ppd, IB_PORT_ACTIVE, 1000);
if (ret) {
- /* logical state didn't change, stay at armed */
- ppd->host_link_state = HLS_UP_ARMED;
dd_dev_err(dd,
"%s: logical state did not change to ACTIVE\n",
__func__);
} else {
/* tell all engines to go running */
sdma_all_running(dd);
+ ppd->host_link_state = HLS_UP_ACTIVE;
/* Signal the IB layer that the port has went active */
event.device = &dd->verbs_dev.rdi.ibdev;