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Subject: Re: [PATCH v4 08/35] iommu/mediatek: Use kmalloc for protect buffer
To:     Yong Wu <yong.wu@mediatek.com>, Joerg Roedel <joro@8bytes.org>,
        Rob Herring <robh+dt@kernel.org>,
        Matthias Brugger <matthias.bgg@gmail.com>,
        Will Deacon <will@kernel.org>
Cc:     Robin Murphy <robin.murphy@arm.com>,
        Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>,
        Tomasz Figa <tfiga@chromium.org>,
        linux-mediatek@lists.infradead.org, srv_heupstream@mediatek.com,
        devicetree@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-arm-kernel@lists.infradead.org,
        iommu@lists.linux-foundation.org,
        Hsin-Yi Wang <hsinyi@chromium.org>, youlin.pei@mediatek.com,
        anan.sun@mediatek.com, xueqi.zhang@mediatek.com,
        yen-chang.chen@mediatek.com, mingyuan.ma@mediatek.com,
        yf.wang@mediatek.com, libo.kang@mediatek.com,
        chengci.xu@mediatek.com
References: <20220125085634.17972-1-yong.wu@mediatek.com>
 <20220125085634.17972-9-yong.wu@mediatek.com>
From:   AngeloGioacchino Del Regno 
        <angelogioacchino.delregno@collabora.com>
Message-ID: <ca47becf-adc9-f11e-5e59-03f203920344@collabora.com>
Date:   Thu, 27 Jan 2022 12:08:14 +0100
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Il 25/01/22 09:56, Yong Wu ha scritto:
> No need zero for the protect buffer that is only accessed by the IOMMU HW
> translation fault happened.
> 
> Signed-off-by: Yong Wu <yong.wu@mediatek.com>

I would rather keep this a devm_kzalloc instead... the cost is very minimal and
this will be handy when new hardware will be introduced, as it may require a bigger
buffer: in that case, "older" platforms will use only part of it and we may get
garbage data at the end.

Regards,
Angelo