Date: Mon, 8 Jun 2015 17:21:47 +0200
From: Joerg Roedel <joro@8bytes.org>
To: David Woodhouse <dwmw2@infradead.org>
Cc: "Li, Zhen-Hua" <zhen-hual@hp.com>, indou.takao@jp.fujitsu.com,
        bhe@redhat.com, vgoyal@redhat.com, dyoung@redhat.com,
        iommu@lists.linux-foundation.org, linux-kernel@vger.kernel.org,
        linux-pci@vger.kernel.org, kexec@lists.infradead.org,
        alex.williamson@redhat.com, ddutile@redhat.com,
        ishii.hironobu@jp.fujitsu.com, bhelgaas@google.com, doug.hatch@hp.com,
        jerry.hoemann@hp.com, tom.vaden@hp.com, li.zhang6@hp.com,
        lisa.mitchell@hp.com, billsumnerlinux@gmail.com, rwright@hp.com
Subject: Re: [PATCH v11 04/10] iommu/vt-d: functions to copy data from old mem
Message-ID: <20150608152147.GV20384@8bytes.org>
References: <1431337974-545-1-git-send-email-zhen-hual@hp.com>
 <1431337974-545-5-git-send-email-zhen-hual@hp.com>
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Hi David,

On Mon, Jun 08, 2015 at 03:15:35PM +0100, David Woodhouse wrote:
> Surely this isn't specific to the Intel IOMMU? Shouldn't it live
> elsewhere — either in generic IOMMU code or perhaps in generic kexec
> support code?

I put a bigger rework of this on-top of Zhen-Hua's patches, you can find
the result in my x86/vt-d branch. With my patches I also removed this
pointer collecting concept and do the iomap_cache and iounmap calls
before the spin-lock is taken, so this problem is now solved
differently.

> And I think you're misusing VTD_PAGE_{SHIFT,MASK} when you should be
> using the normal PAGE_{SHIFT,MASK}.

I think VT_PAGE_* is correct, since the VT-d driver also runs on ia64.
There the system page-size is different from the VT-d page-size.

>And shouldn't physical addresses be phys_addr_t?

This is changed where appropriate, I hope.


	Joerg

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