1 files changed, 7 insertions, 3 deletions

diff --git a/drivers/infiniband/hw/ipath/ipath_file_ops.c b/drivers/infiniband/hw/ipath/ipath_file_ops.c
index 5de3243a47c..92dae6f5b39 100644
--- a/drivers/infiniband/hw/ipath/ipath_file_ops.c
+++ b/drivers/infiniband/hw/ipath/ipath_file_ops.c
@@ -2149,11 +2149,15 @@ static int ipath_get_slave_info(struct ipath_portdata *pd,
 
 static int ipath_force_pio_avail_update(struct ipath_devdata *dd)
 {
-        u64 reg = dd->ipath_sendctrl;
+        unsigned long flags;
 
-        clear_bit(IPATH_S_PIOBUFAVAILUPD, &reg);
-        ipath_write_kreg(dd, dd->ipath_kregs->kr_sendctrl, reg);
+        spin_lock_irqsave(&dd->ipath_sendctrl_lock, flags);
+        ipath_write_kreg(dd, dd->ipath_kregs->kr_sendctrl,
+                dd->ipath_sendctrl & ~INFINIPATH_S_PIOBUFAVAILUPD);
+        ipath_read_kreg64(dd, dd->ipath_kregs->kr_scratch);
         ipath_write_kreg(dd, dd->ipath_kregs->kr_sendctrl, dd->ipath_sendctrl);
+        ipath_read_kreg64(dd, dd->ipath_kregs->kr_scratch);
+        spin_unlock_irqrestore(&dd->ipath_sendctrl_lock, flags);
 
         return 0;
 }