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Date:   Thu, 24 Feb 2022 17:51:41 -0500
From:   Steven Rostedt <rostedt@goodmis.org>
To:     Josh Poimboeuf <jpoimboe@redhat.com>
Cc:     Masami Hiramatsu <mhiramat@kernel.org>,
        Peter Zijlstra <peterz@infradead.org>, x86@kernel.org,
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        alyssa.milburn@intel.com, mbenes@suse.cz,
        alexei.starovoitov@gmail.com
Subject: Re: [PATCH v2 12/39] x86/ibt,ftrace: Search for __fentry__ location
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On Thu, 24 Feb 2022 14:46:31 -0800
Josh Poimboeuf <jpoimboe@redhat.com> wrote:

> > > > > +			rec = lookup_rec(ip - offset, (ip - offset) + size);  
> 
> If 'offset' is zero then why the math here?      ^^^^^^^^^^^   ^^^^^^^^^^^

Because it didn't check for offset being zero when we wrote that line. ;-)

Yes, checking for !offset makes that logic irrelevant.

Good catch.

-- Steve