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Date:   Wed, 7 Sep 2022 14:56:52 +0200
From:   Peter Zijlstra <peterz@infradead.org>
To:     "Masami Hiramatsu (Google)" <mhiramat@kernel.org>
Cc:     Steven Rostedt <rostedt@goodmis.org>,
        Ingo Molnar <mingo@kernel.org>,
        Suleiman Souhlal <suleiman@google.com>,
        bpf <bpf@vger.kernel.org>, linux-kernel@vger.kernel.org,
        Borislav Petkov <bp@suse.de>,
        Josh Poimboeuf <jpoimboe@kernel.org>, x86@kernel.org
Subject: Re: [PATCH 1/2] x86/kprobes: Fix kprobes instruction boudary check
 with CONFIG_RETHUNK
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References: <166251211081.632004.1842371136165709807.stgit@devnote2>
 <166251212072.632004.16078953024905883328.stgit@devnote2>
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On Wed, Sep 07, 2022 at 09:55:21AM +0900, Masami Hiramatsu (Google) wrote:

>  	if (!kallsyms_lookup_size_offset(paddr, NULL, &offset))
>  		return 0;
>  

One more thing:

  https://lkml.kernel.org/r/20220902130951.853460809@infradead.org

can result in negative offsets. The expression:

	'paddr - offset'

will still get you to +0, but I might not have fully considered things
when I wrote that patch.