From a891b97b3bce93420d2b0d165a6b84bbb98b4388 Mon Sep 17 00:00:00 2001
From: Gleb Chesnokov <gleb.chesnokov@scst.dev>
Date: Mon, 8 Aug 2022 18:56:24 +0300
Subject: [PATCH] qla2x00t-32gbit: Zero undefined mailbox IN registers

While requesting a new mailbox command, driver does not write any data to
unused registers.  Initialize the unused register value to zero while
requesting a new mailbox command to prevent stale entry access by firmware.

Link: https://lore.kernel.org/r/20220713052045.10683-4-njavali@marvell.com
Cc: stable@vger.kernel.org
Reviewed-by: Himanshu Madhani <himanshu.madhani@oracle.com>
Signed-off-by: Bikash Hazarika <bhazarika@marvell.com>
Signed-off-by: Quinn Tran <qutran@marvell.com>
Signed-off-by: Nilesh Javali <njavali@marvell.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
[ commit 6c96a3c7d495 upstream ]
---
 qla2x00t-32gbit/qla_mbx.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/qla2x00t-32gbit/qla_mbx.c b/qla2x00t-32gbit/qla_mbx.c
index 643fa0052..9a3f832c4 100644
--- a/qla2x00t-32gbit/qla_mbx.c
+++ b/qla2x00t-32gbit/qla_mbx.c
@@ -238,6 +238,8 @@ qla2x00_mailbox_command(scsi_qla_host_t *vha, mbx_cmd_t *mcp)
 			ql_dbg(ql_dbg_mbx, vha, 0x1112,
 			    "mbox[%d]<-0x%04x\n", cnt, *iptr);
 			wrt_reg_word(optr, *iptr);
+		} else {
+			wrt_reg_word(optr, 0);
 		}
 
 		mboxes >>= 1;