Re: [PATCH v2 4/5] x86/bpf: Fix 64-bit JIT frame pointer usage

From: Alexei Starovoitov
Date: Fri Jun 14 2019 - 20:07:44 EST


On Fri, Jun 14, 2019 at 4:54 PM Josh Poimboeuf <jpoimboe@xxxxxxxxxx> wrote:
>
> On Fri, Jun 14, 2019 at 04:23:41PM -0700, Alexei Starovoitov wrote:
> > On Fri, Jun 14, 2019 at 4:13 PM Josh Poimboeuf <jpoimboe@xxxxxxxxxx> wrote:
> > >
> > > On Fri, Jun 14, 2019 at 02:27:30PM -0700, Alexei Starovoitov wrote:
> > > > On Fri, Jun 14, 2019 at 2:19 PM Josh Poimboeuf <jpoimboe@xxxxxxxxxx> wrote:
> > > > >
> > > > > On Fri, Jun 14, 2019 at 02:05:56PM -0700, Alexei Starovoitov wrote:
> > > > > > Have you tested it ?
> > > > > > I really doubt, since in my test both CONFIG_UNWINDER_ORC and
> > > > > > CONFIG_UNWINDER_FRAME_POINTER failed to unwind through such odd frame.
> > > > >
> > > > > Hm, are you seeing selftest failures? They seem to work for me.
> > > > >
> > > > > > Here is much simple patch that I mentioned in the email yesterday,
> > > > > > but you failed to listen instead of focusing on perceived 'code readability'.
> > > > > >
> > > > > > It makes one proper frame and both frame and orc unwinders are happy.
> > > > >
> > > > > I'm on my way out the door and I just skimmed it, but it looks fine.
> > > > >
> > > > > Some of the code and patch description look familiar, please be sure to
> > > > > give me proper credit.
> > > >
> > > > credit means something positive.
> > >
> > > So you only give credit for *good* stolen code. I must have missed that
> > > section of the kernel patch guidelines.
> >
> > what are you talking about?
> > you've posted one bad patch. I pointed out multiple issues in it.
> > Then proposed another bad idea. I pointed out another set of issues.
> > Than David proposed yet another idea that you've implemented
> > and claimed that it's working when it was not.
> > Then I got fed up with this thread and fix it for real by reverting
> > that old commit that I mentioned way earlier.
> > https://patchwork.ozlabs.org/patch/1116307/
> > Where do you see your code or ideas being used?
> > I see none.
>
> Obviously I wasn't referring to this new whitewashed patch for which I
> wasn't even on Cc, despite being one of the people (along with Peter Z)
> who convinced you that there was a problem to begin with.

vger has a small limit on cc list. I always trim it to the minimum.

> The previous patch you posted has my patch description, push/pop and
> comment changes, with no credit:

I'm sorry for reusing one sentence from your commit log and
not realizing you want credit for that.
Will not happen again.
I also suggest you never touch anything bpf related.
Just to avoid this credit claims and threads like this one.