From: Qing Wang <wangqing@vivo.com>
To: Vladimir Oltean <vladimir.oltean@nxp.com>,
Claudiu Manoil <claudiu.manoil@nxp.com>,
Alexandre Belloni <alexandre.belloni@bootlin.com>,
UNGLinuxDriver@microchip.com, Andrew Lunn <andrew@lunn.ch>,
Vivien Didelot <vivien.didelot@gmail.com>,
Florian Fainelli <f.fainelli@gmail.com>,
"David S. Miller" <davem@davemloft.net>,
Jakub Kicinski <kuba@kernel.org>,
netdev@vger.kernel.org, linux-kernel@vger.kernel.org
Cc: Wang Qing <wangqing@vivo.com>
Subject: [PATCH] net: dsa: ocelot: use div64_u64() instead of do_div()
Date: Wed, 9 Feb 2022 00:39:02 -0800 [thread overview]
Message-ID: <1644395942-4186-1-git-send-email-wangqing@vivo.com> (raw)
From: Wang Qing <wangqing@vivo.com>
do_div() does a 64-by-32 division.
When the divisor is u64, do_div() truncates it to 32 bits, this means it
can test non-zero and be truncated to zero for division.
fix do_div.cocci warning:
do_div() does a 64-by-32 division, please consider using div64_u64 instead.
Signed-off-by: Wang Qing <wangqing@vivo.com>
---
drivers/net/dsa/ocelot/felix_vsc9959.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/net/dsa/ocelot/felix_vsc9959.c b/drivers/net/dsa/ocelot/felix_vsc9959.c
index bf8d382..5c2482f
--- a/drivers/net/dsa/ocelot/felix_vsc9959.c
+++ b/drivers/net/dsa/ocelot/felix_vsc9959.c
@@ -1178,7 +1178,7 @@ static void vsc9959_new_base_time(struct ocelot *ocelot, ktime_t base_time,
if (base_time < current_time) {
u64 nr_of_cycles = current_time - base_time;
- do_div(nr_of_cycles, cycle_time);
+ div64_u64(nr_of_cycles, cycle_time);
new_base_time += cycle_time * (nr_of_cycles + 1);
}
--
2.7.4
next reply other threads:[~2022-02-09 8:41 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-02-09 8:39 Qing Wang [this message]
2022-02-09 11:14 ` [PATCH] net: dsa: ocelot: use div64_u64() instead of do_div() Vladimir Oltean
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