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Date:   Thu, 6 Jun 2019 19:58:26 -0400
From:   Josh Poimboeuf <jpoimboe@redhat.com>
To:     Song Liu <songliubraving@fb.com>
Cc:     Kairui Song <kasong@redhat.com>, Alexei Starovoitov <ast@fb.com>,
        Peter Zijlstra <peterz@infradead.org>,
        lkml <linux-kernel@vger.kernel.org>,
        Kernel Team <Kernel-team@fb.com>,
        Alexei Starovoitov <ast@kernel.org>,
        Daniel Borkmann <daniel@iogearbox.net>,
        "bpf@vger.kernel.org" <bpf@vger.kernel.org>
Subject: Re: Getting empty callchain from perf_callchain_kernel()
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On Thu, Jun 06, 2019 at 04:04:48PM +0000, Song Liu wrote:
> >> Here's a tentative BPF fix for the JIT frame pointer issue.  It was a
> >> bit harder than I expected.  Encoding r12 as a base register requires a
> >> SIB byte, so I had to add support for encoding that.  I also simplified
> >> the prologue to resemble a GCC prologue, which decreases the prologue
> >> size quite a bit.
> >> 
> >> Next week I can work on the corresponding ORC change.  Then I can clean
> >> all the patches up and submit them properly.
> 
> Hi Josh, 
> 
> Have you got luck fixing the ORC side?

Sorry, I've been traveling this week and I haven't had a chance to work
on it.  It's at the top of my TODO list for next week.

-- 
Josh