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Subject: Re: [PATCH v10 3/4] powerpc/powernv: Override
 pcibios_default_alignment() to force PCI devices to be page aligned
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Bjorn Helgaas <bhelgaas@google.com>
Cc: Bjorn Helgaas <helgaas@kernel.org>, Yongji Xie <elohimes@gmail.com>,
        "linux-pci@vger.kernel.org" <linux-pci@vger.kernel.org>,
        linuxppc-dev
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        "alex.williamson@redhat.com"
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        Gavin Shan <gwshan@linux.vnet.ibm.com>,
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        Michael Ellerman
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        "paulus@samba.org" <paulus@samba.org>,
        Li Zhong
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Date: Sun, 16 Apr 2017 08:06:14 +1000
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On Sat, 2017-04-15 at 11:36 -0500, Bjorn Helgaas wrote:
> > I agree in principle. I'm surprised that PowerPC is the only one
> > interested here though, what about other platforms who want to use
> > KVM and PCI pass-through and use Linux to assign BARs ?
> 
> If I understand correctly, the problem is with BARs smaller than a
> page, and this happens more on PowerPC because larger page sizes are
> more common there.

Yes, it happens "more". That doesn't mean it doesn't happen at all on
others :-) Anyway, I'm not objecting, just surprised.

Cheers,
Ben.