From mboxrd@z Thu Jan 1 00:00:00 1970 From: Marc Zyngier Subject: Re: [PATCH 1/6] ARM: kvm: psci: fix handling of unimplemented functions Date: Tue, 09 Jun 2015 18:18:20 +0100 Message-ID: <55771FDC.3090800@arm.com> References: <1432901799-18359-1-git-send-email-lorenzo.pieralisi@arm.com> <1432901799-18359-2-git-send-email-lorenzo.pieralisi@arm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1432901799-18359-2-git-send-email-lorenzo.pieralisi-5wv7dgnIgG8@public.gmane.org> Sender: devicetree-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Lorenzo Pieralisi , "linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org" , "devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" Cc: Christoffer Dall , Anup Patel , Will Deacon , Sudeep Holla , Catalin Marinas , Mark Rutland List-Id: devicetree@vger.kernel.org Hi Lorenzo, On 29/05/15 13:16, Lorenzo Pieralisi wrote: > According to the PSCI specification and the SMC/HVC calling > convention, PSCI function_ids that are not implemented must > return NOT_SUPPORTED as return value. > > Current KVM implementation takes an unhandled PSCI function_id > as an error and injects an undefined instruction into the guest > if PSCI implementation is called with a function_id that is not > handled by the resident PSCI version (ie it is not implemented), > which is not the behaviour expected by a guest when calling a > PSCI function_id that is not implemented. > > This patch fixes this issue by returning NOT_SUPPORTED whenever > the kvm PSCI call is executed for a function_id that is not > implemented by the PSCI kvm layer. > > Signed-off-by: Lorenzo Pieralisi > Reported-by: Sudeep Holla > Cc: Christoffer Dall > Cc: Anup Patel > Cc: Marc Zyngier > --- > arch/arm/kvm/psci.c | 6 +++--- > 1 file changed, 3 insertions(+), 3 deletions(-) > > diff --git a/arch/arm/kvm/psci.c b/arch/arm/kvm/psci.c > index 7e9398c..ec5943b 100644 > --- a/arch/arm/kvm/psci.c > +++ b/arch/arm/kvm/psci.c > @@ -273,7 +273,8 @@ static int kvm_psci_0_2_call(struct kvm_vcpu *vcpu) > ret = 0; > break; > default: > - return -EINVAL; > + val = PSCI_RET_NOT_SUPPORTED; > + break; > } > > *vcpu_reg(vcpu, 0) = val; > @@ -295,10 +296,9 @@ static int kvm_psci_0_1_call(struct kvm_vcpu *vcpu) > break; > case KVM_PSCI_FN_CPU_SUSPEND: > case KVM_PSCI_FN_MIGRATE: > + default: > val = PSCI_RET_NOT_SUPPORTED; > break; > - default: > - return -EINVAL; > } > > *vcpu_reg(vcpu, 0) = val; > Looks good to me. How do you want to proceed with this one? can I take it independently from the rest of the series? Or would you prefer it being kept as a whole? Thanks, M. -- Jazz is not dead. It just smells funny... -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html From mboxrd@z Thu Jan 1 00:00:00 1970 From: marc.zyngier@arm.com (Marc Zyngier) Date: Tue, 09 Jun 2015 18:18:20 +0100 Subject: [PATCH 1/6] ARM: kvm: psci: fix handling of unimplemented functions In-Reply-To: <1432901799-18359-2-git-send-email-lorenzo.pieralisi@arm.com> References: <1432901799-18359-1-git-send-email-lorenzo.pieralisi@arm.com> <1432901799-18359-2-git-send-email-lorenzo.pieralisi@arm.com> Message-ID: <55771FDC.3090800@arm.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Hi Lorenzo, On 29/05/15 13:16, Lorenzo Pieralisi wrote: > According to the PSCI specification and the SMC/HVC calling > convention, PSCI function_ids that are not implemented must > return NOT_SUPPORTED as return value. > > Current KVM implementation takes an unhandled PSCI function_id > as an error and injects an undefined instruction into the guest > if PSCI implementation is called with a function_id that is not > handled by the resident PSCI version (ie it is not implemented), > which is not the behaviour expected by a guest when calling a > PSCI function_id that is not implemented. > > This patch fixes this issue by returning NOT_SUPPORTED whenever > the kvm PSCI call is executed for a function_id that is not > implemented by the PSCI kvm layer. > > Signed-off-by: Lorenzo Pieralisi > Reported-by: Sudeep Holla > Cc: Christoffer Dall > Cc: Anup Patel > Cc: Marc Zyngier > --- > arch/arm/kvm/psci.c | 6 +++--- > 1 file changed, 3 insertions(+), 3 deletions(-) > > diff --git a/arch/arm/kvm/psci.c b/arch/arm/kvm/psci.c > index 7e9398c..ec5943b 100644 > --- a/arch/arm/kvm/psci.c > +++ b/arch/arm/kvm/psci.c > @@ -273,7 +273,8 @@ static int kvm_psci_0_2_call(struct kvm_vcpu *vcpu) > ret = 0; > break; > default: > - return -EINVAL; > + val = PSCI_RET_NOT_SUPPORTED; > + break; > } > > *vcpu_reg(vcpu, 0) = val; > @@ -295,10 +296,9 @@ static int kvm_psci_0_1_call(struct kvm_vcpu *vcpu) > break; > case KVM_PSCI_FN_CPU_SUSPEND: > case KVM_PSCI_FN_MIGRATE: > + default: > val = PSCI_RET_NOT_SUPPORTED; > break; > - default: > - return -EINVAL; > } > > *vcpu_reg(vcpu, 0) = val; > Looks good to me. How do you want to proceed with this one? can I take it independently from the rest of the series? Or would you prefer it being kept as a whole? Thanks, M. -- Jazz is not dead. It just smells funny...