IB/hfi1: Fix abba locking issue with sc_disable()

sc_disable() after having disabled the send context wakes up any waiters
by calling hfi1_qp_wakeup() while holding the waitlock for the sc.

This is contrary to the model for all other calls to hfi1_qp_wakeup()
where the waitlock is dropped and a local is used to drive calls to
hfi1_qp_wakeup().

Fix by moving the sc->piowait into a local list and driving the wakeup
calls from the list.

Fixes: 099a884ba4 ("IB/hfi1: Handle wakeup of orphaned QPs for pio")
Link: https://lore.kernel.org/r/20211013141852.128104.2682.stgit@awfm-01.cornelisnetworks.com
Signed-off-by: Mike Marciniszyn <mike.marciniszyn@cornelisnetworks.com>
Reported-by: TOTE Robot <oslab@tsinghua.edu.cn>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@cornelisnetworks.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
This commit is contained in:
Mike Marciniszyn 2021-10-13 10:18:52 -04:00 committed by Jason Gunthorpe
parent d39bf40e55
commit 13bac86195

View File

@ -878,6 +878,7 @@ void sc_disable(struct send_context *sc)
{ {
u64 reg; u64 reg;
struct pio_buf *pbuf; struct pio_buf *pbuf;
LIST_HEAD(wake_list);
if (!sc) if (!sc)
return; return;
@ -912,19 +913,21 @@ void sc_disable(struct send_context *sc)
spin_unlock(&sc->release_lock); spin_unlock(&sc->release_lock);
write_seqlock(&sc->waitlock); write_seqlock(&sc->waitlock);
while (!list_empty(&sc->piowait)) { if (!list_empty(&sc->piowait))
list_move(&sc->piowait, &wake_list);
write_sequnlock(&sc->waitlock);
while (!list_empty(&wake_list)) {
struct iowait *wait; struct iowait *wait;
struct rvt_qp *qp; struct rvt_qp *qp;
struct hfi1_qp_priv *priv; struct hfi1_qp_priv *priv;
wait = list_first_entry(&sc->piowait, struct iowait, list); wait = list_first_entry(&wake_list, struct iowait, list);
qp = iowait_to_qp(wait); qp = iowait_to_qp(wait);
priv = qp->priv; priv = qp->priv;
list_del_init(&priv->s_iowait.list); list_del_init(&priv->s_iowait.list);
priv->s_iowait.lock = NULL; priv->s_iowait.lock = NULL;
hfi1_qp_wakeup(qp, RVT_S_WAIT_PIO | HFI1_S_WAIT_PIO_DRAIN); hfi1_qp_wakeup(qp, RVT_S_WAIT_PIO | HFI1_S_WAIT_PIO_DRAIN);
} }
write_sequnlock(&sc->waitlock);
spin_unlock_irq(&sc->alloc_lock); spin_unlock_irq(&sc->alloc_lock);
} }