FAILED: patch "[PATCH] scsi: qla2xxx: Zero undefined mailbox IN registers" failed to apply to 4.19-stable tree

[<gregkh@linuxfoundation.org>]

The patch below does not apply to the 4.19-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@vger.kernel.org>.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 6c96a3c7d49593ef15805f5e497601c87695abc9 Mon Sep 17 00:00:00 2001
From: Bikash Hazarika <bhazarika@marvell.com>
Date: Tue, 12 Jul 2022 22:20:38 -0700
Subject: [PATCH] scsi: qla2xxx: 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>

diff --git a/drivers/scsi/qla2xxx/qla_mbx.c b/drivers/scsi/qla2xxx/qla_mbx.c
index 643fa0052f5a..9a3f832c49ef 100644
--- a/drivers/scsi/qla2xxx/qla_mbx.c
+++ b/drivers/scsi/qla2xxx/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;