From mboxrd@z Thu Jan 1 00:00:00 1970 From: Julien Grall Subject: Re: [PATCH v4 16/16] xen/arm: add SGI handling for GICv3 Date: Thu, 12 Jun 2014 22:56:54 +0100 Message-ID: <539A2226.2020403@linaro.org> References: <1401100009-7326-1-git-send-email-vijay.kilari@gmail.com> <1401100009-7326-17-git-send-email-vijay.kilari@gmail.com> <538CA395.4000905@linaro.org> <53984DD2.3030804@linaro.org> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii"; Format="flowed" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: Vijay Kilari Cc: Ian Campbell , Stefano Stabellini , Prasun Kapoor , Vijaya Kumar K , "xen-devel@lists.xen.org" , Stefano Stabellini List-Id: xen-devel@lists.xenproject.org On 12/06/14 07:53, Vijay Kilari wrote: > In GICv3 case the sending SGI by guest raises sysreg trap where > as in GICv2 it raises mmio write trap. So these traps lands in respective > vgic driver. ( mmio write trap => vgic-v2.c and sysreg => vgic-v3.c) > These vgic-v{2,3}.c driver calls generic vgic driver to inject SGI to VCPU. What does prevent a malicious buggy gicv2 guest too call the sysreg version? AFAIU nothing, so you will end up to interpret GICv2 data as GICv3 data which will result to a possible security issue. > If I understand correctly, you mean creating callback in vgic, which is > common function in vgic driver and from there it should call > respective vgic-v{2,3}.c driver. Yes, I see that on your new version you didn't use a callback. Please use it. Regards, -- Julien Grall