[PATCH 4.14 64/94] net: ena: fix missing calls to READ_ONCE

[Greg Kroah-Hartman]

4.14-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Netanel Belgazal <netanel@xxxxxxxxxx>

[ Upstream commit 28abf4e9c9201eda5c4d29ea609d07e877b464b8 ]

Add READ_ONCE calls where necessary (for example when iterating
over a memory field that gets updated by the hardware).

Signed-off-by: Netanel Belgazal <netanel@xxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 drivers/net/ethernet/amazon/ena/ena_com.c |    8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

--- a/drivers/net/ethernet/amazon/ena/ena_com.c
+++ b/drivers/net/ethernet/amazon/ena/ena_com.c
@@ -457,7 +457,7 @@ static void ena_com_handle_admin_complet
 	cqe = &admin_queue->cq.entries[head_masked];
 
 	/* Go over all the completions */
-	while ((cqe->acq_common_descriptor.flags &
+	while ((READ_ONCE(cqe->acq_common_descriptor.flags) &
 			ENA_ADMIN_ACQ_COMMON_DESC_PHASE_MASK) == phase) {
 		/* Do not read the rest of the completion entry before the
 		 * phase bit was validated
@@ -633,7 +633,7 @@ static u32 ena_com_reg_bar_read32(struct
 	writel(mmio_read_reg, ena_dev->reg_bar + ENA_REGS_MMIO_REG_READ_OFF);
 
 	for (i = 0; i < timeout; i++) {
-		if (read_resp->req_id == mmio_read->seq_num)
+		if (READ_ONCE(read_resp->req_id) == mmio_read->seq_num)
 			break;
 
 		udelay(1);
@@ -1790,8 +1790,8 @@ void ena_com_aenq_intr_handler(struct en
 	aenq_common = &aenq_e->aenq_common_desc;
 
 	/* Go over all the events */
-	while ((aenq_common->flags & ENA_ADMIN_AENQ_COMMON_DESC_PHASE_MASK) ==
-	       phase) {
+	while ((READ_ONCE(aenq_common->flags) &
+		ENA_ADMIN_AENQ_COMMON_DESC_PHASE_MASK) == phase) {
 		pr_debug("AENQ! Group[%x] Syndrom[%x] timestamp: [%llus]\n",
 			 aenq_common->group, aenq_common->syndrom,
 			 (u64)aenq_common->timestamp_low +