From mboxrd@z Thu Jan 1 00:00:00 1970 From: Paolo Bonzini Subject: Re: [PATCH] x86:kvm:Fix error handling in the function kvm_lapic_sync_from_vapic Date: Wed, 5 Aug 2015 16:54:58 +0200 Message-ID: <55C223C2.6040701@redhat.com> References: <1438785880-25434-1-git-send-email-xerofoify@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Cc: x86@kernel.org, kvm@vger.kernel.org, linux-kernel@vger.kernel.org To: Nicholas Krause , gleb@kernel.org Return-path: In-Reply-To: <1438785880-25434-1-git-send-email-xerofoify@gmail.com> Sender: linux-kernel-owner@vger.kernel.org List-Id: kvm.vger.kernel.org On 05/08/2015 16:44, Nicholas Krause wrote: > This fixes error handling in the function kvm_lapic_sync_from_vapic > by checking if the call to kvm_read_guest_cached has returned a > error code to signal to its caller the call to this function has > failed and due to this we must immediately return to the caller > of kvm_lapic_sync_from_vapic to avoid incorrectly call apic_set_tpc > if a error has occurred here. > > Signed-off-by: Nicholas Krause > --- > arch/x86/kvm/lapic.c | 5 +++-- > 1 file changed, 3 insertions(+), 2 deletions(-) > > diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c > index 2a5ca97..9a3e342 100644 > --- a/arch/x86/kvm/lapic.c > +++ b/arch/x86/kvm/lapic.c > @@ -1900,8 +1900,9 @@ void kvm_lapic_sync_from_vapic(struct kvm_vcpu *vcpu) > if (!test_bit(KVM_APIC_CHECK_VAPIC, &vcpu->arch.apic_attention)) > return; > > - kvm_read_guest_cached(vcpu->kvm, &vcpu->arch.apic->vapic_cache, &data, > - sizeof(u32)); > + if (kvm_read_guest_cached(vcpu->kvm, &vcpu->arch.apic->vapic_cache, &data, > + sizeof(u32))) > + return; > > apic_set_tpr(vcpu->arch.apic, data & 0xff); > } > Congratulations, this patch is good! :) I'm applying it to kvm.git's queue branch. Paolo