From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dennis Dalessandro Subject: [PATCH 03/10] IB/hfi1: Fix hard lockup due to not using save/restore spin lock Date: Tue, 24 May 2016 12:50:23 -0700 Message-ID: <20160524195022.19706.52616.stgit@scvm10.sc.intel.com> References: <20160524194746.19706.42976.stgit@scvm10.sc.intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20160524194746.19706.42976.stgit-9QXIwq+3FY+1XWohqUldA0EOCMrvLtNR@public.gmane.org> Sender: linux-rdma-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: dledford-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org Cc: linux-rdma-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Mike Marciniszyn , Sebastian Sanchez , stable-u79uwXL29TY76Z2rM5mHXA@public.gmane.org#4.6+ List-Id: linux-rdma@vger.kernel.org From: Mike Marciniszyn Commit b9b06cb6feda ("IB/hfi1: Fix missing lock/unlock in verbs drain callback") added a spin lock. Unfortunately, the new lock code can be called from a base level interrupt state, and an interrupt that can get stacked will attempt to get the same lock. Fix by using the flag save/restore spin lock variation. Cc: stable-u79uwXL29TY76Z2rM5mHXA@public.gmane.org # 4.6+ Reviewed-by: Sebastian Sanchez Signed-off-by: Mike Marciniszyn Signed-off-by: Dennis Dalessandro --- drivers/infiniband/hw/hfi1/qp.c | 5 +++-- 1 files changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/infiniband/hw/hfi1/qp.c b/drivers/infiniband/hw/hfi1/qp.c index 14f889e..1a942ff 100644 --- a/drivers/infiniband/hw/hfi1/qp.c +++ b/drivers/infiniband/hw/hfi1/qp.c @@ -512,6 +512,7 @@ static void iowait_wakeup(struct iowait *wait, int reason) static void iowait_sdma_drained(struct iowait *wait) { struct rvt_qp *qp = iowait_to_qp(wait); + unsigned long flags; /* * This happens when the send engine notes @@ -519,12 +520,12 @@ static void iowait_sdma_drained(struct iowait *wait) * do the flush work until that QP's * sdma work has finished. */ - spin_lock(&qp->s_lock); + spin_lock_irqsave(&qp->s_lock, flags); if (qp->s_flags & RVT_S_WAIT_DMA) { qp->s_flags &= ~RVT_S_WAIT_DMA; hfi1_schedule_send(qp); } - spin_unlock(&qp->s_lock); + spin_unlock_irqrestore(&qp->s_lock, flags); } /** -- To unsubscribe from this list: send the line "unsubscribe linux-rdma" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html