From mboxrd@z Thu Jan 1 00:00:00 1970
From: marc.zyngier@arm.com (Marc Zyngier)
Date: Wed, 16 Sep 2015 16:58:05 +0100
Subject: [PATCH 1/3] arm/arm64: KVM: vgic: Check for !irqchip_in_kernel() when
mapping resources
In-Reply-To: <1442419087-24648-1-git-send-email-marc.zyngier@arm.com>
References: <1442419087-24648-1-git-send-email-marc.zyngier@arm.com>
Message-ID: <1442419087-24648-2-git-send-email-marc.zyngier@arm.com>
To: linux-arm-kernel@lists.infradead.org
List-Id: linux-arm-kernel.lists.infradead.org
From: Pavel Fedin
Until b26e5fdac43c ("arm/arm64: KVM: introduce per-VM ops"),
kvm_vgic_map_resources() used to include a check on irqchip_in_kernel(),
and vgic_v2_map_resources() still has it.
But now vm_ops are not initialized until we call kvm_vgic_create().
Therefore kvm_vgic_map_resources() can being called without a VGIC,
and we die because vm_ops.map_resources is NULL.
Fixing this restores QEMU's kernel-irqchip=off option to a working state,
allowing to use GIC emulation in userspace.
Fixes: b26e5fdac43c ("arm/arm64: KVM: introduce per-VM ops")
Cc: stable at vger.kernel.org
Signed-off-by: Pavel Fedin
[maz: reworked commit message]
Signed-off-by: Marc Zyngier
---
arch/arm/kvm/arm.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/arm/kvm/arm.c b/arch/arm/kvm/arm.c
index ce404a5..dc017ad 100644
--- a/arch/arm/kvm/arm.c
+++ b/arch/arm/kvm/arm.c
@@ -446,7 +446,7 @@ static int kvm_vcpu_first_run_init(struct kvm_vcpu *vcpu)
* Map the VGIC hardware resources before running a vcpu the first
* time on this VM.
*/
- if (unlikely(!vgic_ready(kvm))) {
+ if (unlikely(irqchip_in_kernel(kvm) && !vgic_ready(kvm))) {
ret = kvm_vgic_map_resources(kvm);
if (ret)
return ret;
--
2.1.4