Messages in this thread Patch in this message | | | From | Huibin Hong <> | Subject | [PATCH v2] watchdog: dw_wdt: fix overflow issue in dw_wdt_top_in_seconds | Date | Tue, 15 Aug 2017 10:45:13 +0800 |
| |
If top is 15, (1 << (16 + top)) may be negative.
Signed-off-by: Huibin Hong <huibin.hong@rock-chips.com> ---
Changes in v2: - Rebase mainline Linux 4.13-rc5
drivers/watchdog/dw_wdt.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/drivers/watchdog/dw_wdt.c b/drivers/watchdog/dw_wdt.c index 36be987..59ed958 100644 --- a/drivers/watchdog/dw_wdt.c +++ b/drivers/watchdog/dw_wdt.c @@ -72,7 +72,9 @@ static inline int dw_wdt_top_in_seconds(struct dw_wdt *dw_wdt, unsigned top) * There are 16 possible timeout values in 0..15 where the number of * cycles is 2 ^ (16 + i) and the watchdog counts down. */ - return (1U << (16 + top)) / dw_wdt->rate; + unsigned int cycles = 1 << (16 + top); + + return (cycles / clk_get_rate(dw_wdt.clk)); } static int dw_wdt_get_top(struct dw_wdt *dw_wdt) -- 1.9.1
| |