Re: [Y2038] [PATCH v4 4/4] input: serio: Replace timeval by timespec64

From: Deepa Dinamani
Date: Sat Dec 16 2017 - 16:37:21 EST


On Thu, Dec 14, 2017 at 1:45 PM, Ben Hutchings
<ben.hutchings@xxxxxxxxxxxxxxx> wrote:
> On Thu, 2017-12-07 at 10:13 -0800, Deepa Dinamani wrote:
>> struct timeval is not y2038 safe.
>> All references to timeval will be deleted from the
>> kernel to make it y2038 safe.
>> Replace its uses by y2038 safe struct timespec64.
>>
>> The timestamps changed here only keep track of delta
>> times. These timestamps are also internal to kernel.
>> Hence, monotonic times are sufficient here.
>> The unit of the delta times is also changed in certain
>> cases to nanoseconds rather than microseconds. This is
>> in line with timespec64 which keeps time in nanoseconds.
> [...]
>> --- a/drivers/input/serio/hil_mlc.c
>> +++ b/drivers/input/serio/hil_mlc.c
> [...]
>> @@ -466,7 +466,7 @@ static const struct hilse_node hil_mlc_se[HILSEN_END] = {
>> FUNC(hilse_init_lcv, 0, HILSEN_NEXT, HILSEN_SLEEP, 0)
>>
>> /* 1 HILSEN_RESTART */
>> - FUNC(hilse_inc_lcv, 10, HILSEN_NEXT, HILSEN_START, 0)
>> + FUNC(hilse_inc_lcv, 10000, HILSEN_NEXT, HILSEN_START, 0)
> [...]
>
> The second macro argument here ends up as the second argument to
> hilse_inc_lcv() which appears to limit the number of retries, not a
> time limit. So I don't think the value here (or wherever else
> hilse_inc_lcv is referenced) should be changed.

I think I misread the code here.

> The EXPECT, EXPECT_LAST etc. macros take a timeout ('to' parameter)
> which is then assigned to hil_mlc::intimeout, so it seems that those
> *should* be scaled up, but this patch doesn't do that. It also doesn't
> change the type of hil_mlc::intimeout (suseconds_t implying units of
> microseconds) or the comment on hilse_node::arg.

Yes, I have overlooked the suseconds_t here. So apart from what you
point out IN() and a few other things should also be fixed.

I will drop this patch and repost the series as Arnd mentioned he
already posted a version of this patch. The series can go in without
it and if we prefer my version here, I can submit the patch alone.

Thanks,
-Deepa