[PATCH 5.12 225/700] nvme-pci: fix var. type for increasing cq_head

From: Greg Kroah-Hartman
Date: Mon Jul 12 2021 - 03:32:33 EST


From: JK Kim <jongkang.kim2@xxxxxxxxx>

[ 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@xxxxxxxxx>
Signed-off-by: Christoph Hellwig <hch@xxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
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 c92a15c3fbc5..4555e9202851 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