On 3/30/2019 6:42 AM Stephen Boyd wrote: >Quoting nixiaoming (2019-03-29 02:05:24) >> In the function divider_recalc_rate The judgment of the return value of > >Please write divider_recalc_rate() with parenthesis to show it's a >function. > >> _get_div indicates that the return value of _get_div may be 0. > >__get_div() Thank you for your guidance, I will correct it later in the patch.
>> In order to avoid the divide-by-zero error, add check the return value >> of _get_div in the divider_ro_round_rate_parent >> >> Signed-off-by: nixiaoming <nixiaom...@huawei.com> > >Is this your name? nixiaoming? Or is it written some other way? Chinese name 倪小明 >> --- >> drivers/clk/clk-divider.c | 2 ++ >> 1 file changed, 2 insertions(+) >> >> diff --git a/drivers/clk/clk-divider.c b/drivers/clk/clk-divider.c >> index e5a1726..0854e3e 100644 >> --- a/drivers/clk/clk-divider.c >> +++ b/drivers/clk/clk-divider.c >> @@ -347,6 +347,8 @@ long divider_ro_round_rate_parent(struct clk_hw *hw, >> struct clk_hw *parent, >> int div; >> >> div = _get_div(table, val, flags, width); >> + if (!div) /* avoid divide-by-zero */ >> + return -EINVAL; > >How does _get_div() return 0? What is the value of 'flags' here when >this goes wrong? divider_ro_round_rate_parent() and divider_recalc_rate() are functions of the EXPORT_SYMBOL_GPL attribute If _get_div() can return 0 in the argument of divider_recalc_rate() Then should be able to return 0 in divider_ro_round_rate_parent() > >> >> /* Even a read-only clock can propagate a rate change */ >> if (clk_hw_get_flags(hw) & CLK_SET_RATE_PARENT) { >> -- >> 1.8.5.6 >> > >Wow that's a 5 year old version of git! > >