IB/hfi1: Fix hard lockup due to not using save/restore spin lock

Commit b9b06cb6fe
("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>
This commit is contained in:
Mike Marciniszyn 2016-05-24 12:50:23 -07:00 committed by Doug Ledford
parent bdd8a98ce4
commit 7049de65c9

View file

@ -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);
}
/**