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From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
To: Jakub Kicinski <kuba@kernel.org>
Cc: wen.yang@linux.dev, Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	stable@vger.kernel.org, linux-kernel@vger.kernel.org,
	Paolo Abeni <pabeni@redhat.com>
Subject: Re: [PATCH 6.6 3/3] net: Allow to use SMP threads for backlog NAPI.
Message-ID: <20260119163026.aA1PeSmP@linutronix.de>
References: <cover.1768751557.git.wen.yang@linux.dev>
 <997bc0de4746100bb69e1bd2ccfb25315d8f62e4.1768751557.git.wen.yang@linux.dev>
 <20260119082534.1f705011@kernel.org>
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In-Reply-To: <20260119082534.1f705011@kernel.org>

On 2026-01-19 08:25:34 [-0800], Jakub Kicinski wrote:
> On Mon, 19 Jan 2026 00:15:46 +0800 wen.yang@linux.dev wrote:
> > From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
> > 
> > commit dad6b97702639fba27a2bd3e986982ad6f0db3a7 upstream.
> > 
> > Backlog NAPI is a per-CPU NAPI struct only (with no device behind it)
> > used by drivers which don't do NAPI them self, RPS and parts of the
> > stack which need to avoid recursive deadlocks while processing a packet.
> 
> This is a rather large change to backport into LTS.

I agree. While I saw these patches flying by, I don't remember a mail
where it was justified why it was needed. Did I miss it?

Sebastian