linux-kernel - [PATCH v2 10/22] watchdog: ziirave_wdt: Zero out only what's necessary

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Date:   Mon, 12 Aug 2019 13:08:54 -0700
From:   Andrey Smirnov <andrew.smirnov@...il.com>
To:     linux-watchdog@...r.kernel.org
Cc:     Andrey Smirnov <andrew.smirnov@...il.com>,
        Chris Healy <cphealy@...il.com>,
        Guenter Roeck <linux@...ck-us.net>,
        Rick Ramstetter <rick@...eaterllc.com>,
        linux-kernel@...r.kernel.org
Subject: [PATCH v2 10/22] watchdog: ziirave_wdt: Zero out only what's necessary

Instead of zeroing out all of the packet and then overwriting a
significant portion of those zeros via memcpy(), zero out only a
portion of the packet that is known to not contain any data.

Signed-off-by: Andrey Smirnov <andrew.smirnov@...il.com>
Cc: Chris Healy <cphealy@...il.com>
Cc: Guenter Roeck <linux@...ck-us.net>
Cc: Rick Ramstetter <rick@...eaterllc.com>
Cc: linux-watchdog@...r.kernel.org
Cc: linux-kernel@...r.kernel.org
---
 drivers/watchdog/ziirave_wdt.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/watchdog/ziirave_wdt.c b/drivers/watchdog/ziirave_wdt.c
index e0f55cbdc603..69694f2836d7 100644
--- a/drivers/watchdog/ziirave_wdt.c
+++ b/drivers/watchdog/ziirave_wdt.c
@@ -260,8 +260,6 @@ static int __ziirave_firm_write_pkt(struct watchdog_device *wdd,
 		return -EMSGSIZE;
 	}
 
-	memset(packet, 0, sizeof(packet));
-
 	/* Packet length */
 	packet[0] = len;
 	/* Packet address */
@@ -269,6 +267,7 @@ static int __ziirave_firm_write_pkt(struct watchdog_device *wdd,
 	packet[2] = (addr16 & 0xff00) >> 8;
 
 	memcpy(packet + 3, data, len);
+	memset(packet + 3 + len, 0, ZIIRAVE_FIRM_PKT_DATA_SIZE - len);
 
 	/* Packet checksum */
 	for (i = 0; i < len + 3; i++)
-- 
2.21.0