Re: [PATCH v2 1/5] perf/x86: Always store regs->ip in perf_callchain_kernel()

[Alexei Starovoitov]

On Fri, Jun 14, 2019 at 12:56:40PM -0500, Josh Poimboeuf wrote:
> From: Song Liu <songliubraving@xxxxxx>
> 
> The stacktrace_map_raw_tp BPF selftest is failing because the RIP saved
> by perf_arch_fetch_caller_regs() isn't getting saved by
> perf_callchain_kernel().
> 
> This was broken by the following commit:
> 
>   d15d356887e7 ("perf/x86: Make perf callchains work without CONFIG_FRAME_POINTER")
> 
> With that change, when starting with non-HW regs, the unwinder starts
> with the current stack frame and unwinds until it passes up the frame
> which called perf_arch_fetch_caller_regs().  So regs->ip needs to be
> saved deliberately.
> 
> Fixes: d15d356887e7 ("perf/x86: Make perf callchains work without CONFIG_FRAME_POINTER")
> Signed-off-by: Josh Poimboeuf <jpoimboe@xxxxxxxxxx>
> Acked-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>

It's not cool to remove people's SOB.
It's Song's patch. His should be first and your second.