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Sender: Ingo Molnar <mingo.kernel.org@gmail.com>
Date:   Mon, 5 Jul 2021 09:46:33 +0200
From:   Ingo Molnar <mingo@kernel.org>
To:     Masami Hiramatsu <mhiramat@kernel.org>
Cc:     Steven Rostedt <rostedt@goodmis.org>,
        Josh Poimboeuf <jpoimboe@redhat.com>, X86 ML <x86@kernel.org>,
        Daniel Xu <dxu@dxuuu.xyz>, linux-kernel@vger.kernel.org,
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        ast@kernel.org, Thomas Gleixner <tglx@linutronix.de>,
        Borislav Petkov <bp@alien8.de>,
        Peter Zijlstra <peterz@infradead.org>, kernel-team@fb.com,
        yhs@fb.com, linux-ia64@vger.kernel.org,
        Abhishek Sagar <sagar.abhishek@gmail.com>,
        Andrii Nakryiko <andrii.nakryiko@gmail.com>
Subject: Re: [PATCH -tip v8 01/13] ia64: kprobes: Fix to pass correct
 trampoline address to the handler
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* Masami Hiramatsu <mhiramat@kernel.org> wrote:

> Commit e792ff804f49 ("ia64: kprobes: Use generic kretprobe trampoline handler")
> missed to pass the wrong trampoline address (it passes the descriptor address
> instead of function entry address).
> This fixes it to pass correct trampoline address to __kretprobe_trampoline_handler().
> This also changes to use correct symbol dereference function to get the
> function address from the kretprobe_trampoline.
> 
> Fixes: e792ff804f49 ("ia64: kprobes: Use generic kretprobe trampoline handler")
> Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>

A better changelog:

  The following commit:

     Commit e792ff804f49 ("ia64: kprobes: Use generic kretprobe trampoline handler")

  Passed the wrong trampoline address to __kretprobe_trampoline_handler(): it
  passes the descriptor address instead of function entry address.

  Pass the right parameter.

  Also use correct symbol dereference function to get the function address
  from 'kretprobe_trampoline' - an IA64 special.

(Although I realize that much of this goes away just a couple of patches 
later.)

Thanks,

	Ingo