RE: [patch] samples/bpf: silence shift wrapping warning

[David Laight]

From: Alexei Starovoitov
> Sent: 22 January 2017 22:51
> On Sat, Jan 21, 2017 at 07:51:43AM +0300, Dan Carpenter wrote:
> > max_key is a value in the 0-63 range, so on 32 bit systems the shift
> > could wrap.
> >
> > Signed-off-by: Dan Carpenter 
> 
> Looks fine. I think 'net-next' is ok.
> 
> Acked-by: Alexei Starovoitov 
> 
> > diff --git a/samples/bpf/lwt_len_hist_user.c 
> > b/samples/bpf/lwt_len_hist_user.c
> > index ec8f3bb..bd06eef 100644
> > --- a/samples/bpf/lwt_len_hist_user.c
> > +++ b/samples/bpf/lwt_len_hist_user.c
> > @@ -68,7 +68,7 @@ int main(int argc, char **argv)
> > for (i = 1; i <= max_key + 1; i++) {
> > stars(starstr, data[i - 1], max_value, MAX_STARS);
> > printf("%8ld -> %-8ld : %-8ld |%-*s|\n",
> > -  (1l << i) >> 1, (1l << i) - 1, data[i - 1],
> > +  (1ULL << i) >> 1, (1ULL << i) - 1, data[i - 1],
> >MAX_STARS, starstr);
> > }

The format effectors are wrong on 32bit systems.

David

Re: [patch] samples/bpf: silence shift wrapping warning

[Arnaldo Carvalho de Melo]

Em Mon, Jan 23, 2017 at 10:44:34PM -0800, Alexei Starovoitov escreveu:
> On Mon, Jan 23, 2017 at 5:27 AM, Arnaldo Carvalho de Melo
>  wrote:
> > Em Sun, Jan 22, 2017 at 02:51:25PM -0800, Alexei Starovoitov escreveu:
> >> On Sat, Jan 21, 2017 at 07:51:43AM +0300, Dan Carpenter wrote:
> >> > max_key is a value in the 0-63 range, so on 32 bit systems the shift
> >> > could wrap.
> >> >
> >> > Signed-off-by: Dan Carpenter 
> >>
> >> Looks fine. I think 'net-next' is ok.
> >
> > I could process these patches, if that would help,
> 
> Thanks for the offer.
> I don't think there will be conflicts with all the work happening in net-next,
> but it's best to avoid even possibility of it when we can.

Okay sir, I'll let you know when/if the tests I perform building
samples/bpf/ in my containers catch something,

- Arnaldo

> Dan,
> can you please resend the patch cc-ing Dave and netdev ?
> please mention [PATCH net-next] in the subject.
> 
> > - Arnaldo
> >
> >> Acked-by: Alexei Starovoitov 
> >
> >> > diff --git a/samples/bpf/lwt_len_hist_user.c 
> >> > b/samples/bpf/lwt_len_hist_user.c
> >> > index ec8f3bb..bd06eef 100644
> >> > --- a/samples/bpf/lwt_len_hist_user.c
> >> > +++ b/samples/bpf/lwt_len_hist_user.c
> >> > @@ -68,7 +68,7 @@ int main(int argc, char **argv)
> >> > for (i = 1; i <= max_key + 1; i++) {
> >> > stars(starstr, data[i - 1], max_value, MAX_STARS);
> >> > printf("%8ld -> %-8ld : %-8ld |%-*s|\n",
> >> > -  (1l << i) >> 1, (1l << i) - 1, data[i - 1],
> >> > +  (1ULL << i) >> 1, (1ULL << i) - 1, data[i - 1],
> >> >MAX_STARS, starstr);
> >> > }
> >> >

Re: [patch] samples/bpf: silence shift wrapping warning

[Dan Carpenter]

On Mon, Jan 23, 2017 at 10:44:34PM -0800, Alexei Starovoitov wrote:
> On Mon, Jan 23, 2017 at 5:27 AM, Arnaldo Carvalho de Melo
>  wrote:
> > Em Sun, Jan 22, 2017 at 02:51:25PM -0800, Alexei Starovoitov escreveu:
> >> On Sat, Jan 21, 2017 at 07:51:43AM +0300, Dan Carpenter wrote:
> >> > max_key is a value in the 0-63 range, so on 32 bit systems the shift
> >> > could wrap.
> >> >
> >> > Signed-off-by: Dan Carpenter 
> >>
> >> Looks fine. I think 'net-next' is ok.
> >
> > I could process these patches, if that would help,
> 
> Thanks for the offer.
> I don't think there will be conflicts with all the work happening in net-next,
> but it's best to avoid even possibility of it when we can.
> Dan,
> can you please resend the patch cc-ing Dave and netdev ?
> please mention [PATCH net-next] in the subject.
> 

Sure.

regards,
dan carpenter

Re: [patch] samples/bpf: silence shift wrapping warning

[Alexei Starovoitov]

On Mon, Jan 23, 2017 at 5:27 AM, Arnaldo Carvalho de Melo
 wrote:
> Em Sun, Jan 22, 2017 at 02:51:25PM -0800, Alexei Starovoitov escreveu:
>> On Sat, Jan 21, 2017 at 07:51:43AM +0300, Dan Carpenter wrote:
>> > max_key is a value in the 0-63 range, so on 32 bit systems the shift
>> > could wrap.
>> >
>> > Signed-off-by: Dan Carpenter 
>>
>> Looks fine. I think 'net-next' is ok.
>
> I could process these patches, if that would help,

Thanks for the offer.
I don't think there will be conflicts with all the work happening in net-next,
but it's best to avoid even possibility of it when we can.
Dan,
can you please resend the patch cc-ing Dave and netdev ?
please mention [PATCH net-next] in the subject.

> - Arnaldo
>
>> Acked-by: Alexei Starovoitov 
>
>> > diff --git a/samples/bpf/lwt_len_hist_user.c 
>> > b/samples/bpf/lwt_len_hist_user.c
>> > index ec8f3bb..bd06eef 100644
>> > --- a/samples/bpf/lwt_len_hist_user.c
>> > +++ b/samples/bpf/lwt_len_hist_user.c
>> > @@ -68,7 +68,7 @@ int main(int argc, char **argv)
>> > for (i = 1; i <= max_key + 1; i++) {
>> > stars(starstr, data[i - 1], max_value, MAX_STARS);
>> > printf("%8ld -> %-8ld : %-8ld |%-*s|\n",
>> > -  (1l << i) >> 1, (1l << i) - 1, data[i - 1],
>> > +  (1ULL << i) >> 1, (1ULL << i) - 1, data[i - 1],
>> >MAX_STARS, starstr);
>> > }
>> >

Re: [patch] samples/bpf: silence shift wrapping warning

[Arnaldo Carvalho de Melo]

Em Sun, Jan 22, 2017 at 02:51:25PM -0800, Alexei Starovoitov escreveu:
> On Sat, Jan 21, 2017 at 07:51:43AM +0300, Dan Carpenter wrote:
> > max_key is a value in the 0-63 range, so on 32 bit systems the shift
> > could wrap.
> > 
> > Signed-off-by: Dan Carpenter 
> 
> Looks fine. I think 'net-next' is ok.

I could process these patches, if that would help,

- Arnaldo
 
> Acked-by: Alexei Starovoitov 
 
> > diff --git a/samples/bpf/lwt_len_hist_user.c 
> > b/samples/bpf/lwt_len_hist_user.c
> > index ec8f3bb..bd06eef 100644
> > --- a/samples/bpf/lwt_len_hist_user.c
> > +++ b/samples/bpf/lwt_len_hist_user.c
> > @@ -68,7 +68,7 @@ int main(int argc, char **argv)
> > for (i = 1; i <= max_key + 1; i++) {
> > stars(starstr, data[i - 1], max_value, MAX_STARS);
> > printf("%8ld -> %-8ld : %-8ld |%-*s|\n",
> > -  (1l << i) >> 1, (1l << i) - 1, data[i - 1],
> > +  (1ULL << i) >> 1, (1ULL << i) - 1, data[i - 1],
> >MAX_STARS, starstr);
> > }
> >  

Re: [patch] samples/bpf: silence shift wrapping warning

[Alexei Starovoitov]

On Sat, Jan 21, 2017 at 07:51:43AM +0300, Dan Carpenter wrote:
> max_key is a value in the 0-63 range, so on 32 bit systems the shift
> could wrap.
> 
> Signed-off-by: Dan Carpenter 

Looks fine. I think 'net-next' is ok.

Acked-by: Alexei Starovoitov 

> diff --git a/samples/bpf/lwt_len_hist_user.c b/samples/bpf/lwt_len_hist_user.c
> index ec8f3bb..bd06eef 100644
> --- a/samples/bpf/lwt_len_hist_user.c
> +++ b/samples/bpf/lwt_len_hist_user.c
> @@ -68,7 +68,7 @@ int main(int argc, char **argv)
>   for (i = 1; i <= max_key + 1; i++) {
>   stars(starstr, data[i - 1], max_value, MAX_STARS);
>   printf("%8ld -> %-8ld : %-8ld |%-*s|\n",
> -(1l << i) >> 1, (1l << i) - 1, data[i - 1],
> +(1ULL << i) >> 1, (1ULL << i) - 1, data[i - 1],
>  MAX_STARS, starstr);
>   }
>