From mboxrd@z Thu Jan 1 00:00:00 1970 From: cdall@linaro.org (Christoffer Dall) Date: Thu, 18 May 2017 11:47:22 +0200 Subject: [PULL 13/13] KVM: arm/arm64: Hold slots_lock when unregistering kvm io bus devices In-Reply-To: <20170518094722.9926-1-cdall@linaro.org> References: <20170518094722.9926-1-cdall@linaro.org> Message-ID: <20170518094722.9926-14-cdall@linaro.org> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org We were not holding the kvm->slots_lock as required when calling kvm_io_bus_unregister_dev() as required. This only affects the error path, but still, let's do our due diligence. Reported by: Eric Auger Signed-off-by: Christoffer Dall Reviewed-by: Eric Auger --- virt/kvm/arm/vgic/vgic-mmio-v3.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/virt/kvm/arm/vgic/vgic-mmio-v3.c b/virt/kvm/arm/vgic/vgic-mmio-v3.c index 9b0f681..201d5e2 100644 --- a/virt/kvm/arm/vgic/vgic-mmio-v3.c +++ b/virt/kvm/arm/vgic/vgic-mmio-v3.c @@ -614,15 +614,16 @@ int vgic_register_redist_iodev(struct kvm_vcpu *vcpu) mutex_lock(&kvm->slots_lock); ret = kvm_io_bus_register_dev(kvm, KVM_MMIO_BUS, sgi_base, SZ_64K, &sgi_dev->dev); - mutex_unlock(&kvm->slots_lock); if (ret) { kvm_io_bus_unregister_dev(kvm, KVM_MMIO_BUS, &rd_dev->dev); - return ret; + goto out; } vgic->vgic_redist_free_offset += 2 * SZ_64K; - return 0; +out: + mutex_unlock(&kvm->slots_lock); + return ret; } static void vgic_unregister_redist_iodev(struct kvm_vcpu *vcpu) @@ -647,10 +648,12 @@ static int vgic_register_all_redist_iodevs(struct kvm *kvm) if (ret) { /* The current c failed, so we start with the previous one. */ + mutex_lock(&kvm->slots_lock); for (c--; c >= 0; c--) { vcpu = kvm_get_vcpu(kvm, c); vgic_unregister_redist_iodev(vcpu); } + mutex_unlock(&kvm->slots_lock); } return ret; -- 2.9.0