From mboxrd@z Thu Jan  1 00:00:00 1970
From: Julien Grall <julien.grall@citrix.com>
Subject: Re: [RFC PATCH v2 13/22] xen/arm: its: Add virtual ITS
 command support
Date: Wed, 29 Apr 2015 14:16:36 +0100
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To: Manish Jaggi <mjaggi@caviumnetworks.com>, Vijay Kilari <vijay.kilari@gmail.com>
Cc: Ian Campbell <ian.campbell@citrix.com>, Stefano Stabellini <stefano.stabellini@eu.citrix.com>, Prasun Kapoor <Prasun.Kapoor@caviumnetworks.com>, Vijaya Kumar K <vijaya.kumar@caviumnetworks.com>, Julien Grall <julien.grall@linaro.org>, Tim Deegan <tim@xen.org>, "xen-devel@lists.xen.org" <xen-devel@lists.xen.org>, Stefano Stabellini <stefano.stabellini@citrix.com>, manish.jaggi@caviumnetworks.com
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On 29/04/15 14:08, Manish Jaggi wrote:
>>> Do you have any other security concern ?
>> Yes. The one we talked in every mail since the beginning of this thread
>> "polling in EL2". We got several XSA because the hypervisor code wasn't
>> preemptible (see [1])
>>
> We are removing polling using command processing completion which is
> signalled using INT interrupt.

Based on the discussion with Vijay, the completion based on the INT
command doesn't seems the right solution (see in particular [1] and [2])

Could you wait the end of this discussion before starting to implement
something that you may have to throw later?

Regards,

[1] http://lists.xen.org/archives/html/xen-devel/2015-04/msg03038.html
[2] http://lists.xen.org/archives/html/xen-devel/2015-04/msg03056.html

-- 
Julien Grall