Re: [PATCH bpf 1/2] bpf: support PTR_TO_MEM{,_OR_NULL} register spilling

[KP Singh]

On Tue, Jan 12, 2021 at 3:24 PM Gilad Reti <gilad.reti@xxxxxxxxx> wrote:
>
> On Tue, Jan 12, 2021 at 3:57 PM KP Singh <kpsingh@xxxxxxxxxx> wrote:
> >
> > On Tue, Jan 12, 2021 at 10:14 AM Gilad Reti <gilad.reti@xxxxxxxxx> wrote:
> > >
> > > Add support for pointer to mem register spilling, to allow the verifier
> > > to track pointer to valid memory addresses. Such pointers are returned
> >
> > nit: pointers
>
> Thanks
>
> >
> > > for example by a successful call of the bpf_ringbuf_reserve helper.
> > >
> > > This patch was suggested as a solution by Yonghong Song.
> >
> > You can use the "Suggested-by:" tag for this.
>
> Thanks
>
> >
> > >
> > > The patch was partially contibuted by CyberArk Software, Inc.
> >
> > nit: typo *contributed
>
> Thanks. Should I submit a v2 of the patch to correct all of those?

I think it would be nice to do another revision
which also addresses the comments on the other patch.


>
> >
> > Also, I was wondering if "partially" here means someone collaborated with you
> > on the patch? And, in that case:
> >
> > "Co-developed-by:" would be a better tag here.
>
> No, I did it alone. I mentioned CyberArk since I work there and did some of the
> coding during my daily work, so they deserve credit.
>
> >
> > Acked-by: KP Singh <kpsingh@xxxxxxxxxx>
> >
> >
> > >
> > > Fixes: 457f44363a88 ("bpf: Implement BPF ring buffer and verifier
> > > support for it")
> > > Signed-off-by: Gilad Reti <gilad.reti@xxxxxxxxx>
> > > ---
> > >  kernel/bpf/verifier.c | 2 ++
> > >  1 file changed, 2 insertions(+)
> > >
> > > diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
> > > index 17270b8404f1..36af69fac591 100644
> > > --- a/kernel/bpf/verifier.c
> > > +++ b/kernel/bpf/verifier.c
> > > @@ -2217,6 +2217,8 @@ static bool is_spillable_regtype(enum bpf_reg_type type)
> > >         case PTR_TO_RDWR_BUF:
> > >         case PTR_TO_RDWR_BUF_OR_NULL:
> > >         case PTR_TO_PERCPU_BTF_ID:
> > > +       case PTR_TO_MEM:
> > > +       case PTR_TO_MEM_OR_NULL:
> > >                 return true;
> > >         default:
> > >                 return false;
> > > --
> > > 2.27.0
> > >