[PATCH AUTOSEL 5.4 36/45] ionic: update eid test for overflow

From: Sasha Levin
Date: Mon Aug 10 2020 - 15:12:56 EST


From: Shannon Nelson <snelson@xxxxxxxxxxx>

[ Upstream commit 3fbc9bb6ca32d12d4d32a7ae32abef67ac95f889 ]

Fix up our comparison to better handle a potential (but largely
unlikely) wrap around.

Signed-off-by: Shannon Nelson <snelson@xxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/net/ethernet/pensando/ionic/ionic_lif.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/pensando/ionic/ionic_lif.c b/drivers/net/ethernet/pensando/ionic/ionic_lif.c
index c00ec9a020973..e66002251596b 100644
--- a/drivers/net/ethernet/pensando/ionic/ionic_lif.c
+++ b/drivers/net/ethernet/pensando/ionic/ionic_lif.c
@@ -666,7 +666,7 @@ static bool ionic_notifyq_service(struct ionic_cq *cq,
eid = le64_to_cpu(comp->event.eid);

/* Have we run out of new completions to process? */
- if (eid <= lif->last_eid)
+ if ((s64)(eid - lif->last_eid) <= 0)
return false;

lif->last_eid = eid;
--
2.25.1