From 5efd40cad4bf98f0d1f6b726d67e39decd85edc9 Mon Sep 17 00:00:00 2001 From: Alex Estrin Date: Sat, 29 Jul 2017 08:43:20 -0700 Subject: [PATCH] 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 Signed-off-by: Alex Estrin Signed-off-by: Dennis Dalessandro Signed-off-by: Doug Ledford --- drivers/infiniband/hw/hfi1/chip.c | 9 +++------ 1 file changed, 3 insertions(+), 6 deletions(-) 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; -- 2.7.4