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From:   Michael Walle <michael@walle.cc>
To:     netdev@vger.kernel.org, linux-kernel@vger.kernel.org
Cc:     Claudiu Manoil <claudiu.manoil@nxp.com>,
        "David S . Miller" <davem@davemloft.net>,
        Jakub Kicinski <kuba@kernel.org>,
        Vladimir Oltean <vladimir.oltean@nxp.com>,
        Michael Walle <michael@walle.cc>
Subject: [PATCH net-next v2] net: enetc: use get/put_unaligned helpers for MAC address handling
Date:   Fri,  4 Jun 2021 15:42:12 +0200
Message-Id: <20210604134212.6982-1-michael@walle.cc>
MIME-Version: 1.0
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The supplied buffer for the MAC address might not be aligned. Thus
doing a 32bit (or 16bit) access could be on an unaligned address. For
now, enetc is only used on aarch64 which can do unaligned accesses, thus
there is no error. In any case, be correct and use the get/put_unaligned
helpers.

Signed-off-by: Michael Walle <michael@walle.cc>
---
changes since v1:
 - explicitly use the little endian variant of the helpers

 drivers/net/ethernet/freescale/enetc/enetc_pf.c | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/drivers/net/ethernet/freescale/enetc/enetc_pf.c b/drivers/net/ethernet/freescale/enetc/enetc_pf.c
index 31274325159a..c84f6c226743 100644
--- a/drivers/net/ethernet/freescale/enetc/enetc_pf.c
+++ b/drivers/net/ethernet/freescale/enetc/enetc_pf.c
@@ -1,6 +1,7 @@
 // SPDX-License-Identifier: (GPL-2.0+ OR BSD-3-Clause)
 /* Copyright 2017-2019 NXP */
 
+#include <asm/unaligned.h>
 #include <linux/mdio.h>
 #include <linux/module.h>
 #include <linux/fsl/enetc_mdio.h>
@@ -17,15 +18,15 @@ static void enetc_pf_get_primary_mac_addr(struct enetc_hw *hw, int si, u8 *addr)
 	u32 upper = __raw_readl(hw->port + ENETC_PSIPMAR0(si));
 	u16 lower = __raw_readw(hw->port + ENETC_PSIPMAR1(si));
 
-	*(u32 *)addr = upper;
-	*(u16 *)(addr + 4) = lower;
+	put_unaligned_le32(upper, addr);
+	put_unaligned_le16(lower, addr + 4);
 }
 
 static void enetc_pf_set_primary_mac_addr(struct enetc_hw *hw, int si,
 					  const u8 *addr)
 {
-	u32 upper = *(const u32 *)addr;
-	u16 lower = *(const u16 *)(addr + 4);
+	u32 upper = get_unaligned_le32(addr);
+	u16 lower = get_unaligned_le16(addr + 4);
 
 	__raw_writel(upper, hw->port + ENETC_PSIPMAR0(si));
 	__raw_writew(lower, hw->port + ENETC_PSIPMAR1(si));
-- 
2.20.1