From mboxrd@z Thu Jan 1 00:00:00 1970 From: Julia Lawall Subject: Re: KVM: x86: question about kvm_ioapic_destroy Date: Mon, 27 Apr 2015 14:32:38 +0200 (CEST) Message-ID: References: <20150427120342-mutt-send-email-mst@redhat.com> Mime-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Cc: Julia Lawall , zhanghy@sangfor.com, jasowang@redhat.com, pbonzini@redhat.com, x86@kernel.org, kvm@vger.kernel.org, linux-kernel@vger.kernel.org To: "Michael S. Tsirkin" Return-path: In-Reply-To: <20150427120342-mutt-send-email-mst@redhat.com> Sender: linux-kernel-owner@vger.kernel.org List-Id: kvm.vger.kernel.org On Mon, 27 Apr 2015, Michael S. Tsirkin wrote: > On Sun, Apr 26, 2015 at 07:19:58PM +0200, Julia Lawall wrote: > > The function kvm_ioapic_destroy is defined as follows: > > > > void kvm_ioapic_destroy(struct kvm *kvm) > > { > > struct kvm_ioapic *ioapic = kvm->arch.vioapic; > > > > cancel_delayed_work_sync(&ioapic->eoi_inject); > > if (ioapic) { > > kvm_io_bus_unregister_dev(kvm, KVM_MMIO_BUS, &ioapic->dev); > > kvm->arch.vioapic = NULL; > > kfree(ioapic); > > } > > } > > > > Is there any way that cancel_delayed_work_sync can work if ioapic is NULL? > > Should the call be moved down under the NULL test? Or is the NULL test > > not needed? The NULL test has been there longer than the call to > > cancel_delayed_work_sync, which was introduced in 184564ef. > > > > thanks, > > julia > > I think the NULL test is not needed. > kvm_ioapic_destroy is only called if kvm_ioapic_init > completed successfully, and that sets kvm->arch.vioapic. Thanks. I will send a patch. julia