From mboxrd@z Thu Jan 1 00:00:00 1970 From: Julien Grall Subject: Re: [PATCH v2 04/19] xen: arm: provide and use a handle_raz_wi helper Date: Sat, 25 Apr 2015 22:09:27 +0500 Message-ID: <553BCA47.8080607@citrix.com> References: <1429279300.25195.330.camel@citrix.com> <1429279315-32143-4-git-send-email-ian.campbell@citrix.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii"; Format="flowed" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1429279315-32143-4-git-send-email-ian.campbell@citrix.com> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: Ian Campbell , xen-devel@lists.xen.org Cc: julien.grall@linaro.org, tim@xen.org, stefano.stabellini@eu.citrix.com List-Id: xen-devel@lists.xenproject.org Hi Ian, On 17/04/2015 19:01, Ian Campbell wrote: > Reduces the use of goto in the trap handlers to none. > > Some explicitly 32-bit types become register_t here, but that's OK, on > 32-bit they are 32-bit already and on 64-bit it is fine/harmless to > set the larger register, a 32-bit guest won't see the top half in any > case. > > Per section B1.2.1 (ARMv8 DDI0487 A.d) writes to wN registers are zero > extended, so there is no risk of leaking the top half here. > > Unlike the previous code the advancing of PC is handled within the > helper, rather than after the end of the switch as before. So return > as the handler is called. > > Signed-off-by: Ian Campbell Reviewed-by: Julien Grall Regards, -- Julien Grall