From mboxrd@z Thu Jan 1 00:00:00 1970 From: Christoffer Dall Subject: Re: [PATCH v3 44/59] KVM: arm/arm64: GICv4: Handle MOVI applied to a VLPI Date: Mon, 28 Aug 2017 20:18:17 +0200 Message-ID: <20170828181817.GE24649@cbox> References: <20170731172637.29355-1-marc.zyngier@arm.com> <20170731172637.29355-45-marc.zyngier@arm.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Cc: Jason Cooper , kvm@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Thomas Gleixner , kvmarm@lists.cs.columbia.edu To: Marc Zyngier Return-path: Content-Disposition: inline In-Reply-To: <20170731172637.29355-45-marc.zyngier@arm.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: kvmarm-bounces@lists.cs.columbia.edu Sender: kvmarm-bounces@lists.cs.columbia.edu List-Id: kvm.vger.kernel.org On Mon, Jul 31, 2017 at 06:26:22PM +0100, Marc Zyngier wrote: > When the guest issues a MOVI, we need to tell the physical ITS > that we're now targetting a new vcpu. This is done by extracting > the current mapping, updating the target, and reapplying the > mapping. The core ITS code should do the right thing. > > Signed-off-by: Marc Zyngier > --- > virt/kvm/arm/vgic/vgic-its.c | 13 +++++++++++++ > 1 file changed, 13 insertions(+) > > diff --git a/virt/kvm/arm/vgic/vgic-its.c b/virt/kvm/arm/vgic/vgic-its.c > index 79bac93d3e7d..aaad577ce328 100644 > --- a/virt/kvm/arm/vgic/vgic-its.c > +++ b/virt/kvm/arm/vgic/vgic-its.c > @@ -706,6 +706,19 @@ static int vgic_its_cmd_handle_movi(struct kvm *kvm, struct vgic_its *its, > ite->irq->target_vcpu = vcpu; > spin_unlock(&ite->irq->irq_lock); > > + if (ite->irq->hw) { > + struct its_vlpi_map map; > + int ret; > + > + ret = its_get_vlpi(ite->irq->host_irq, &map); > + if (ret) > + return ret; > + > + map.vpe_idx = vcpu->vcpu_id; > + > + return its_map_vlpi(ite->irq->host_irq, &map); Since you're not holding the irq_lock across these two calls, would it be possible that the forwarding was removed through some other call path here, and could you end up passing an invalid host_irq to its_map_vlpi? Thanks, -Christoffer > + } > + > return 0; > } > > -- > 2.11.0 >