Re: [PATCH HID for-next v3 1/5] bpf: do not rely on ALLOW_ERROR_INJECTION for fmod_ret
From: Alexei Starovoitov
Date: Wed Dec 07 2022 - 16:58:43 EST
On Wed, Dec 7, 2022 at 6:57 AM Benjamin Tissoires
<benjamin.tissoires@xxxxxxxxxx> wrote:
>
> On Tue, Dec 6, 2022 at 9:48 PM Alexei Starovoitov
> <alexei.starovoitov@xxxxxxxxx> wrote:
> >
> > On Tue, Dec 6, 2022 at 6:59 AM Benjamin Tissoires
> > <benjamin.tissoires@xxxxxxxxxx> wrote:
> > >
> > > The current way of expressing that a non-bpf kernel component is willing
> > > to accept that bpf programs can be attached to it and that they can change
> > > the return value is to abuse ALLOW_ERROR_INJECTION.
> > > This is debated in the link below, and the result is that it is not a
> > > reasonable thing to do.
> > >
> > > Reuse the kfunc declaration structure to also tag the kernel functions
> > > we want to be fmodret. This way we can control from any subsystem which
> > > functions are being modified by bpf without touching the verifier.
> > >
> > >
> > > Link: https://lore.kernel.org/all/20221121104403.1545f9b5@xxxxxxxxxxxxxxxxxx/
> > > Suggested-by: Alexei Starovoitov <alexei.starovoitov@xxxxxxxxx>
> > > Signed-off-by: Benjamin Tissoires <benjamin.tissoires@xxxxxxxxxx>
> >
> > BPF CI couldn't do its job because of a merge conflict.
> > CI only tries to apply the whole series.
> > But I tested the patch 1 manually.
> > Everything is green on x86-64 and the patch looks good.
> >
> > Acked-by: Alexei Starovoitov <ast@xxxxxxxxxx>
> >
> > Please send the set during the merge window.
> > If not we can take just this patch,
> > since the series from Viktor Malik would need this patch too.
> >
>
> Thanks a lot for the quick review/tests Alexei.
>
> I have now taken this patch and the next into the hid tree.
>
> I actually took this patch through a branch attached to our hid.git
> master branch so compared to Linus, it only has this one patch. I also
> tagged (and signed) that very same branch with "for-alexei-2022120701"
> in case you also want to bring this one in through the bpf tree too.
I didn't find such a branch in your tree, but found that tag
and pulled into bpf-next.
Thanks!