From: Keir Fraser <keir@xen.org>
To: "G.R." <firemeteor@users.sourceforge.net>
Cc: Stefano Stabellini <stefano.stabellini@citrix.com>,
Ian Campbell <Ian.Campbell@citrix.com>,
"Jean.guyader@gmail.com" <Jean.guyader@gmail.com>,
xen-devel <xen-devel@lists.xen.org>
Subject: Re: [PATCH] hvmloader / qemu-xen: Getting rid of resource conflict for OpRegion.
Date: Thu, 20 Dec 2012 14:19:22 +0000 [thread overview]
Message-ID: <CCF8CEEA.561B5%keir@xen.org> (raw)
In-Reply-To: <CAKhsbWZ2mCUj6=XM9XDYZqMEei3PcFC7WXKiK48Y5KH+5s_MgQ@mail.gmail.com>
On 20/12/2012 13:31, "G.R." <firemeteor@users.sourceforge.net> wrote:
> If concern is about security, the same argument should apply to the
> first page (the portion before the page offset).
> The problem is that I have no idea what is around the mapped page. Not
> sure who has the knowledge.
Well we can't do better than mapping some whole number of pages, really.
Unless we trap to qemu on every access. I don't think we'd go there unless
there really were a known security issue. But mapping only the exact number
of pages we definitely need is a good principle.
> What's the standard flow to handle such map with offset?
> I expect this to be a common case, since the ioremap function in linux
> kernel accept this.
map_size = ((host_opregion & 0xfff) + 8096 + 0xfff) >> 12
Possibly with suitable macros used instead of magic numbers (e.g., XC_PAGE_*
and a macro for the opregion size).
-- Keir
next prev parent reply other threads:[~2012-12-20 14:19 UTC|newest]
Thread overview: 26+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-12-20 3:52 [PATCH] hvmloader / qemu-xen: Getting rid of resource conflict for OpRegion G.R.
2012-12-20 3:56 ` G.R.
2012-12-20 10:41 ` Ian Campbell
2012-12-20 13:03 ` Keir Fraser
2012-12-20 13:31 ` G.R.
2012-12-20 14:19 ` Keir Fraser [this message]
2012-12-20 15:06 ` G.R.
2012-12-20 18:27 ` Ross Philipson
2012-12-21 3:59 ` G.R.
2012-12-21 15:55 ` Ross Philipson
2012-12-21 16:49 ` G.R.
2012-12-21 17:03 ` Ross Philipson
2012-12-21 17:26 ` Ross Philipson
2012-12-23 6:11 ` G.R.
2013-01-02 16:34 ` Ross Philipson
2013-01-04 7:25 ` G.R.
2013-01-09 15:34 ` G.R.
2013-01-09 16:36 ` Ross Philipson
2013-01-10 10:27 ` G.R.
2013-01-10 13:40 ` Ross Philipson
2013-01-10 16:29 ` G.R.
2013-01-14 16:01 ` Ross Philipson
2013-01-15 16:44 ` G.R.
2012-12-20 19:44 ` Jean Guyader
2012-12-20 19:50 ` Ian Campbell
2012-12-21 3:51 ` G.R.
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