Re: [GIT PULL] time/ntp fix

From: Geert Uytterhoeven
Date: Sun Feb 22 2015 - 15:29:26 EST


Hi Ingo,

On Sat, Feb 21, 2015 at 6:49 AM, Ingo Molnar <mingo@xxxxxxxxxx> wrote:
> * John Stultz <john.stultz@xxxxxxxxxx> wrote:
>
>> On Fri, Feb 20, 2015 at 2:26 PM, Linus Torvalds
>> <torvalds@xxxxxxxxxxxxxxxxxxxx> wrote:
>> > On Fri, Feb 20, 2015 at 5:44 AM, Ingo Molnar <mingo@xxxxxxxxxx> wrote:
>> >>
>> >> John Stultz (1):
>> >> ntp: Fixup adjtimex freq validation on 32-bit systems
>> >
>> > This is confusing. 32-bit?
>>
>> Right, so the check that was added in a previous commit
>> is really only a concern for 64bit systems, but was
>> applied to both 32 and 64bit systems, which results in
>> breaking 32bit systems.
>>
>> Thus the "fix" here is to make the check only apply to
>> 64bit systems.
>
> Yeah, perhaps a better commit title would have been to
> write:
>
> time/ntp: Fix adjtimex freq validation code build warning on 32-bit systems
>
> To make it clear that the problem fixed is a 32-bit
> warning, and that the fix for that is to only check on
> 64-bit systems.
>
> I agreed with your BITS_PER_LONG check when I reviewed your
> patch, people usually do an ugly #ifdef, I think this
> in line check form is nicer.

Unfortunately it doesn't help with all compiler versions.
With gcc 4.1.2 for m68k:

kernel/time/ntp.c: In function ântp_validate_timexâ:
kernel/time/ntp.c:641: warning: comparison is always false due to
limited range of data type
kernel/time/ntp.c:643: warning: comparison is always false due to
limited range of data type

Gcc 4.6.3 and 4.9.0 are OK (for m68k).

Gr{oetje,eeting}s,

Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx

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
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