This is a note to let you know that I've just added the patch titled
scsi: ufs: core: Let the sq_lock protect sq_tail_slot access
to the 6.6-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
scsi-ufs-core-let-the-sq_lock-protect-sq_tail_slot-a.patch
and it can be found in the queue-6.6 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 2ce913c6a7939609e67b18f15394a37e59ec04c8
Author: Can Guo <quic_cang@xxxxxxxxxxx>
Date: Mon Dec 18 07:32:17 2023 -0800
scsi: ufs: core: Let the sq_lock protect sq_tail_slot access
[ Upstream commit 04c116e2bdfc3969f9819d2cebfdf678353c354c ]
When accessing sq_tail_slot without protection from sq_lock, a race
condition can cause multiple SQEs to be copied to duplicate SQE slots. This
can lead to multiple stability issues. Fix this by moving the *dest
initialization in ufshcd_send_command() back under protection from the
sq_lock.
Fixes: 3c85f087faec ("scsi: ufs: mcq: Use pointer arithmetic in ufshcd_send_command()")
Signed-off-by: Can Guo <quic_cang@xxxxxxxxxxx>
Link: https://lore.kernel.org/r/1702913550-20631-1-git-send-email-quic_cang@xxxxxxxxxxx
Reviewed-by: Bart Van Assche <bvanassche@xxxxxxx>
Signed-off-by: Martin K. Petersen <martin.petersen@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/ufs/core/ufshcd.c b/drivers/ufs/core/ufshcd.c
index 170fbd5715b21..a885cc177cff7 100644
--- a/drivers/ufs/core/ufshcd.c
+++ b/drivers/ufs/core/ufshcd.c
@@ -2172,9 +2172,10 @@ void ufshcd_send_command(struct ufs_hba *hba, unsigned int task_tag,
if (is_mcq_enabled(hba)) {
int utrd_size = sizeof(struct utp_transfer_req_desc);
struct utp_transfer_req_desc *src = lrbp->utr_descriptor_ptr;
- struct utp_transfer_req_desc *dest = hwq->sqe_base_addr + hwq->sq_tail_slot;
+ struct utp_transfer_req_desc *dest;
spin_lock(&hwq->sq_lock);
+ dest = hwq->sqe_base_addr + hwq->sq_tail_slot;
memcpy(dest, src, utrd_size);
ufshcd_inc_sq_tail(hwq);
spin_unlock(&hwq->sq_lock);
