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Date:   Wed, 4 Mar 2020 11:47:49 -0600
From:   Josh Poimboeuf <jpoimboe@redhat.com>
To:     Miroslav Benes <mbenes@suse.cz>
Cc:     tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, hpa@zytor.com,
        linux-kernel@vger.kernel.org, x86@kernel.org
Subject: Re: [PATCH] x86/unwind/orc: Do not skip the first frame unless
 explicitly asked for
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References: <20200304123259.32199-1-mbenes@suse.cz>
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On Wed, Mar 04, 2020 at 01:32:59PM +0100, Miroslav Benes wrote:
> ORC unwinder can currently skip the first frame even if a user does not
> ask for it. If both regs and first_frame parameters of unwind_start()
> are set to NULL, state->sp and first_frame are later initialized to the
> same value for an inactive task. Given there is "less than or equal to"
> comparison used at the end of __unwind_start() for skipping stack frames,
> the first frame is always skipped in this case.
> 
> Drop the equal part of the comparison and make it equivalent to the
> frame pointer unwinder.
> 
> Signed-off-by: Miroslav Benes <mbenes@suse.cz>

Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>

-- 
Josh