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Message-ID: <87muvwsxfj.wl%kuninori.morimoto.gx@renesas.com>
From:   Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
To:     Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Cc:     Geert Uytterhoeven <geert@linux-m68k.org>, <vkoul@kernel.org>,
        Dan Williams <dan.j.williams@intel.com>,
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        <dmaengine@vger.kernel.org>,
        "open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS" 
        <devicetree@vger.kernel.org>
Subject: Re: [PATCH v2] dmaengine: rcar-dmac: don't use DMAC error interrupt
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Date:   Fri, 15 Jun 2018 00:35:20 +0000
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Hi, again

> > > Current rcar-dmac is using DMAC error interrupt which will handle all
> > > channel's error. But in this design, error handling itself will be
> > > issue if user want to use virtualization, multi OS, etc.
> > > This patch removes current DMAC error interrupt handling, and handle it
> > > on each channel interrupt handler.
> > 
> > Just wondering, what's the usage pattern where this causes a problem?
> > Do you plan to export part of a SYS-DMAC instance to a guest?
> 
> "virtualization, multi OS" part is maybe misleading.
> It will be problem on non virtualization, too.
> 
> > How to maintain host/guest isolation?
> 
> This is another topic/issue, I think

I will post v3 patch, soon


Best regards
---
Kuninori Morimoto