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From: =?utf-8?B?QmrDtnJuIFTDtnBlbA==?= <bjorn@kernel.org>
To: James Hilliard <james.hilliard1@gmail.com>, Russell King
 <linux@armlinux.org.uk>, Andrew Lunn <andrew@lunn.ch>, Heiner Kallweit
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Cc: Richard Genoud <richard.genoud@bootlin.com>, Alastair D'Silva
 <alastair@d-silva.org>, Maxime Ripard <mripard@kernel.org>,
 netdev@vger.kernel.org, linux-kernel@vger.kernel.org,
 linux-stm32@st-md-mailman.stormreply.com,
 linux-arm-kernel@lists.infradead.org, bpf@vger.kernel.org, ZhaoJinming
 <zhaojinming@uniontech.com>, Lorenzo Bianconi
 <lorenzo.bianconi@oss.qualcomm.com>, Ding Hui <dinghui1111@163.com>,
 Linkui Xiao <xiaolinkui@kylinos.cn>, Linkui Xiao <xiaolinkui@126.com>,
 linux-tegra@vger.kernel.org, linux-sunxi@lists.linux.dev, James Hilliard
 <james.hilliard1@gmail.com>
Subject: Re: [PATCH net-next v5 16/19] xsk: allow drivers to retain DMA
 mappings independently of pools
In-Reply-To: <20260927-submit-stmmac-reset-fixes-v1-v5-16-feec6c14dd06@gmail.com>
References: <20260927-submit-stmmac-reset-fixes-v1-v5-0-feec6c14dd06@gmail.com>
 <20260927-submit-stmmac-reset-fixes-v1-v5-16-feec6c14dd06@gmail.com>
Date: Mon, 28 Sep 2026 14:22:58 +0200
Message-ID: <875wzp4lb1.fsf@all.your.base.are.belong.to.us>
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James Hilliard <james.hilliard1@gmail.com> writes:

> An unsuccessful device shutdown does not make its DMA memory safe to
> unmap.

Why does this need an AF_XDP API? Can stmmac fence DMA before releasing
the pool? Please show a case where stop and reset fail, DMA remains
active, and the driver cannot isolate it.


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