releases/5.10.50/nvme-pci-fix-var.-type-for-increasing-cq_head.patch

From 3391a42b073bdaa42ce5c244ce67867952d346a0 Mon Sep 17 00:00:00 2001
From: Sasha Levin <sashal@kernel.org>
Date: Thu, 17 Jun 2021 15:02:17 +0900
Subject: nvme-pci: fix var. type for increasing cq_head

From: JK Kim <jongkang.kim2@gmail.com>

[ Upstream commit a0aac973a26d1ac814b9e131e209eb39472a67ce ]

nvmeq->cq_head is compared with nvmeq->q_depth and changed the value
and cq_phase for handling the next cq db.

but, nvmeq->q_depth's type is u32 and max. value is 0x10000 when
CQP.MSQE is 0xffff and io_queue_depth is 0x10000.

current temp. variable for comparing with nvmeq->q_depth is overflowed
when previous nvmeq->cq_head is 0xffff.

in this case, nvmeq->cq_phase is not updated.
so, fix data type for temp. variable to u32.

Signed-off-by: JK Kim <jongkang.kim2@gmail.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/nvme/host/pci.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c
index c1f3446216c5..56263214ea06 100644
--- a/drivers/nvme/host/pci.c
+++ b/drivers/nvme/host/pci.c
@@ -1027,7 +1027,7 @@ static inline void nvme_handle_cqe(struct nvme_queue *nvmeq, u16 idx)
 
 static inline void nvme_update_cq_head(struct nvme_queue *nvmeq)
 {
-	u16 tmp = nvmeq->cq_head + 1;
+	u32 tmp = nvmeq->cq_head + 1;
 
 	if (tmp == nvmeq->q_depth) {
 		nvmeq->cq_head = 0;
-- 
2.30.2