do_div() does a 64-by-32 division. Here the divisor is an
unsigned long which on some platforms is 64 bit wide. So use
div64_ul instead of do_div to avoid a possible truncation.
Eliminate the following coccicheck warning:
./drivers/net/ethernet/renesas/ravb_main.c:2492:1-7: WARNING:
do_div() does a 64-by-32 division, please consider using div64_ul instead.
Reported-by: Abaci Robot <[email protected]>
Signed-off-by: Yang Li <[email protected]>
---
change in v2:
--Fixed warning message
drivers/net/ethernet/renesas/ravb_main.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/net/ethernet/renesas/ravb_main.c b/drivers/net/ethernet/renesas/ravb_main.c
index b4c597f..2b89710 100644
--- a/drivers/net/ethernet/renesas/ravb_main.c
+++ b/drivers/net/ethernet/renesas/ravb_main.c
@@ -2489,7 +2489,7 @@ static int ravb_set_gti(struct net_device *ndev)
return -EINVAL;
inc = 1000000000ULL << 20;
- do_div(inc, rate);
+ inc = div64_ul(inc, rate);
if (inc < GTI_TIV_MIN || inc > GTI_TIV_MAX) {
dev_err(dev, "gti.tiv increment 0x%llx is outside the range 0x%x - 0x%x\n",
--
1.8.3.1
Hi Yang,
On Thu, Nov 18, 2021 at 4:13 AM Yang Li <[email protected]> wrote:
> do_div() does a 64-by-32 division. Here the divisor is an
> unsigned long which on some platforms is 64 bit wide. So use
> div64_ul instead of do_div to avoid a possible truncation.
>
> Eliminate the following coccicheck warning:
> ./drivers/net/ethernet/renesas/ravb_main.c:2492:1-7: WARNING:
> do_div() does a 64-by-32 division, please consider using div64_ul instead.
>
> Reported-by: Abaci Robot <[email protected]>
> Signed-off-by: Yang Li <[email protected]>
Thanks for your patch!
> --- a/drivers/net/ethernet/renesas/ravb_main.c
> +++ b/drivers/net/ethernet/renesas/ravb_main.c
> @@ -2489,7 +2489,7 @@ static int ravb_set_gti(struct net_device *ndev)
> return -EINVAL;
>
> inc = 1000000000ULL << 20;
> - do_div(inc, rate);
> + inc = div64_ul(inc, rate);
>
> if (inc < GTI_TIV_MIN || inc > GTI_TIV_MAX) {
> dev_err(dev, "gti.tiv increment 0x%llx is outside the range 0x%x - 0x%x\n",
Please also replace
#include <asm/div64.h>
by
#include <linux/math64.h>
With that added:
Reviewed-by: Geert Uytterhoeven <[email protected]>
Gr{oetje,eeting}s,
Geert
--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- [email protected]
In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds