From: Julien Grall <julien.grall@arm.com>
To: David Vrabel <david.vrabel@citrix.com>,
boris.ostrovsky@oracle.com, jgross@suse.com,
sstabellini@kernel.org, konrad.wilk@oracle.com
Cc: andrew.cooper3@citrix.com, xen-devel@lists.xen.org,
linux-kernel@vger.kernel.org, JBeulich@suse.com,
steve.capper@arm.com
Subject: Re: [Xen-devel] [PATCH] xen: grant-table: Check truncation when giving access to a frame
Date: Mon, 13 Jun 2016 12:10:03 +0100 [thread overview]
Message-ID: <575E948B.7060507@arm.com> (raw)
In-Reply-To: <575E9198.70103@citrix.com>
Hi David,
On 13/06/16 11:57, David Vrabel wrote:
> On 13/06/16 11:50, Julien Grall wrote:
>> The version 1 of the grant-table protocol only supports frame encoded on
>> 32-bit.
>>
>> When the platform is supporting 48-bit physical address, the frame will
>> be encoded on 36-bit which will lead a truncation and give access to
>> the wrong frame.
>>
>> On ARM Xen will always allow the guest to use all the physical address,
>> although today the RAM is always located under 40-bits (see
>> xen/include/public/arch-arm.h).
>>
>> Add a truncation check in gnttab_update_entry_v1 to prevent the guest to
>> give access to the wrong frame.
>
> In hindsight, we shouldn't have dropped the V2 support from Linux.
> Should we reinstate it?
What were the reasons to drop the v2 support from Linux? More
importantly why people did choose to stay on v1?
Cheers,
--
Julien Grall
next prev parent reply other threads:[~2016-06-13 11:10 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-06-13 10:50 [PATCH] xen: grant-table: Check truncation when giving access to a frame Julien Grall
2016-06-13 10:57 ` [Xen-devel] " David Vrabel
2016-06-13 11:10 ` Julien Grall [this message]
2016-06-13 12:20 ` Paul Durrant
2016-06-13 12:12 ` Paul Durrant
2016-06-13 12:41 ` Julien Grall
2016-06-13 12:42 ` Julien Grall
2016-06-13 12:45 ` Paul Durrant
2016-06-13 13:05 ` Julien Grall
2016-06-13 13:14 ` Paul Durrant
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=575E948B.7060507@arm.com \
--to=julien.grall@arm.com \
--cc=JBeulich@suse.com \
--cc=andrew.cooper3@citrix.com \
--cc=boris.ostrovsky@oracle.com \
--cc=david.vrabel@citrix.com \
--cc=jgross@suse.com \
--cc=konrad.wilk@oracle.com \
--cc=linux-kernel@vger.kernel.org \
--cc=sstabellini@kernel.org \
--cc=steve.capper@arm.com \
--cc=xen-devel@lists.xen.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox