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Date:   Thu, 15 Apr 2021 14:21:20 -0400
From:   Steven Rostedt <rostedt@goodmis.org>
To:     Jiri Olsa <jolsa@redhat.com>
Cc:     Andrii Nakryiko <andrii.nakryiko@gmail.com>,
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Subject: Re: [PATCHv2 RFC bpf-next 0/7] bpf: Add support for ftrace probe
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On Thu, 15 Apr 2021 14:18:31 -0400
Steven Rostedt <rostedt@goodmis.org> wrote:

> My last release of that code is here:
> 
>   https://lore.kernel.org/lkml/20190525031633.811342628@goodmis.org/
> 
> It allows you to "reserve data" to pass from the caller to the return, and
> that could hold the arguments. See patch 15 of that series.

Note that implementation only lets you save up to 4 words on the stack, but
that can be changed. Or you could have a separate shadow stack for saving
arguments, and only pass the pointer to the location on the other stack
where those arguments are.

-- Steve