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To: Luming Yu <luming.yu@shingroup.cn>, linuxppc-dev@lists.ozlabs.org,
 linux-kernel@vger.kernel.org, mpe@ellerman.id.au, npiggin@gmail.com,
 christophe.leroy@csgroup.eu, luming.yu@gmail.com
Cc: Luming Yu <luming.yu@shingroup.cn>
Subject: Re: [PATCH v2 3/8] powerpc/debug: implement HAVE_USER_RETURN_NOTIFIER
In-Reply-To: <027637B09D70E22F+20241111031934.1579-6-luming.yu@shingroup.cn>
References: <20241111031934.1579-2-luming.yu@shingroup.cn>
 <027637B09D70E22F+20241111031934.1579-6-luming.yu@shingroup.cn>
Date: Wed, 13 Nov 2024 07:48:37 +0100
Message-ID: <874j4bmxx6.ffs@tglx>
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On Mon, Nov 11 2024 at 11:19, Luming Yu wrote:
> enable the common entry of user return notifier for powerpc as
> a debug feature.

What's the debug feature?

There are ZERO user return notifiers registered in PowerPC, so your
"debug feature" is just a waste of CPU cycles.

Thanks,

        tglx