[PATCH AUTOSEL 4.18 45/65] net: ena: fix missing calls to READ_ONCE

From: Sasha Levin
Date: Sun Sep 30 2018 - 20:39:22 EST


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>
---
drivers/net/ethernet/amazon/ena/ena_com.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/net/ethernet/amazon/ena/ena_com.c b/drivers/net/ethernet/amazon/ena/ena_com.c
index 17f12c18d225..c37deef3bcf1 100644
--- a/drivers/net/ethernet/amazon/ena/ena_com.c
+++ b/drivers/net/ethernet/amazon/ena/ena_com.c
@@ -459,7 +459,7 @@ static void ena_com_handle_admin_completion(struct ena_com_admin_queue *admin_qu
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
@@ -637,7 +637,7 @@ static u32 ena_com_reg_bar_read32(struct ena_com_dev *ena_dev, u16 offset)

mmiowb();
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);
@@ -1796,8 +1796,8 @@ void ena_com_aenq_intr_handler(struct ena_com_dev *dev, void *data)
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 +
--
2.17.1