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Date: Mon, 28 May 2018 08:07:57 +0200 (CEST)
From: Thomas Gleixner <tglx@linutronix.de>
To: Christoph Hellwig <hch@lst.de>
cc: Ingo Molnar <mingo@redhat.com>, Tony Luck <tony.luck@intel.com>,
        Fenghua Yu <fenghua.yu@intel.com>,
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Subject: Re: [PATCH 5/7] x86: remove the experimental forcesac boot option
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On Fri, 25 May 2018, Christoph Hellwig wrote:

x86/pci-dma: ...

Please

> Limiting the dma mask to avoid PCI (pre-PCIe) DAC cycles while paying
> the huge overhead of an IOMMU is rather pointless, and this seriously
> gets in the way of dma mapping work.
> 
> Signed-off-by: Christoph Hellwig <hch@lst.de>

Reviewed-by: Thomas Gleixner <tglx@linutronix.de>