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

From: Josh Poimboeuf
Date: Fri Jun 14 2019 - 19:59:20 EST


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.

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

https://lkml.kernel.org/r/20190614210555.q4ictql3tzzjio4r@xxxxxxxxxxxxxxxxxxxxxxxxxxxx

--
Josh