| From 7049de65c9e520886f06d6f9deceaaed5d93fb7c Mon Sep 17 00:00:00 2001 |
| From: Mike Marciniszyn <mike.marciniszyn@intel.com> |
| Date: Tue, 24 May 2016 12:50:23 -0700 |
| Subject: IB/hfi1: Fix hard lockup due to not using save/restore spin lock |
| |
| From: Mike Marciniszyn <mike.marciniszyn@intel.com> |
| |
| commit 7049de65c9e520886f06d6f9deceaaed5d93fb7c upstream. |
| |
| 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@vger.kernel.org # 4.6+ |
| Reviewed-by: Sebastian Sanchez <sebastian.sanchez@intel.com> |
| Signed-off-by: Mike Marciniszyn <mike.marciniszyn@intel.com> |
| Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com> |
| Signed-off-by: Doug Ledford <dledford@redhat.com> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| |
| --- |
| drivers/staging/rdma/hfi1/qp.c | 5 +++-- |
| 1 file changed, 3 insertions(+), 2 deletions(-) |
| |
| --- a/drivers/staging/rdma/hfi1/qp.c |
| +++ b/drivers/staging/rdma/hfi1/qp.c |
| @@ -512,6 +512,7 @@ static void iowait_wakeup(struct iowait |
| 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 i |
| * 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); |
| } |
| |
| /** |
