Re: [Linux-kernel-mentees][PATCH v2] packet: Fix undefined behavior in bit shift

From: Alexei Starovoitov
Date: Thu Jun 27 2019 - 13:06:00 EST


On Thu, Jun 27, 2019 at 9:54 AM Shuah Khan <skhan@xxxxxxxxxxxxxxxxxxx> wrote:
>
> On 6/27/19 10:22 AM, David Miller wrote:
> > From: Shuah Khan <skhan@xxxxxxxxxxxxxxxxxxx>
> > Date: Wed, 26 Jun 2019 21:32:52 -0600
> >
> >> On 6/26/19 9:25 PM, Jiunn Chang wrote:
> >>> Shifting signed 32-bit value by 31 bits is undefined. Changing most
> >>> significant bit to unsigned.
> >>> Changes included in v2:
> >>> - use subsystem specific subject lines
> >>> - CC required mailing lists
> >>>
> >>
> >> These version change lines don't belong in the change log.
> >
> > For networking changes I actually like the change lines to be in the
> > commit log. So please don't stray people this way, thanks.
> >
>
> As a general rule, please don't include change lines in the commit log.
> For networking changes that get sent to David and netdev, as David
> points out here, he likes them in the commit log, please include them
> in the commit log.
>
> I am working on FAQ (Frequently Answered Questions) section for mentees.
> I will add this to it.

Same for bpf trees.
We prefer developers put as much as info as possible into commit logs
and cover letters.
Explanation of v1->v2->v3 differences is invaluable not only at
the point of code review, but in the future.