From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ian Campbell Subject: Re: [PATCH] xen/arm: Make local_events_need_delivery working with idle VPCU Date: Tue, 5 May 2015 13:29:58 +0100 Message-ID: <1430828998.2660.70.camel@citrix.com> References: <1430145540-31032-1-git-send-email-julien.grall@citrix.com> <553E6489.30300@citrix.com> <1430826035.2660.52.camel@citrix.com> <5548B0FB.1000900@citrix.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from mail6.bemta3.messagelabs.com ([195.245.230.39]) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1Ypbz9-00023i-Nm for xen-devel@lists.xenproject.org; Tue, 05 May 2015 12:30:03 +0000 In-Reply-To: <5548B0FB.1000900@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: Julien Grall Cc: Stefano Stabellini , Andrew Cooper , Riku Voipio , Tim Deegan , stefano.stabellini@citrix.com, Jan Beulich , xen-devel@lists.xenproject.org, Tamas K Lengyel List-Id: xen-devel@lists.xenproject.org On Tue, 2015-05-05 at 13:00 +0100, Julien Grall wrote: > > I'm inclined to just go with this patch for now, unless Stefano is > > nacking it. > > This patch seem to turn into a workaround, would it be better to move > check idle_check in apply_p2m_check? > > I will prepare a follow-up to avoid properly the call > hypercall_preempt_check with idle_vcpu. > > > One question first: What aspect of local_events_need_delivery relies on > > the vcpu not being an idle one? I suppose something is not initialised, > > but what. > > Everything related to the vGIC is not initialized. It's used in > local_event_need_delivery_nomask (see irq_to_pending and > gic_events_need_devlivery). Would it be better to arrange that vcpu_event_delivery_is_enabled is never true for an idle vcpu? Either with an explicit check or by arranging regs->cpsr to say that? Ian. >