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From:   Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
To:     Geert Uytterhoeven <geert@linux-m68k.org>
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        <dmaengine@vger.kernel.org>,
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Subject: Re: [PATCH v2] dmaengine: rcar-dmac: don't use DMAC error interrupt
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Hi Geert

Thank you for your feedback

> > 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

Best regards
---
Kuninori Morimoto