Re: [PATCH v2] KVM: SVM: Fix implicit declaration for __default_cpu_present_to_apicid()

From: Paolo Bonzini
Date: Wed Jun 15 2016 - 18:28:22 EST


Thanks, queuing both patches for 4.7-rc.

Paolo

On 16/06/2016 00:23, Suravee Suthikulpanit wrote:
> The commit 8221c1370056 ("svm: Manage vcpu load/unload when enable AVIC")
> introduces a build error due to implicit function declaration
> when #ifdef CONFIG_X86_32 and #ifndef CONFIG_X86_LOCAL_APIC
> (as reported by Kbuild test robot i386-randconfig-x0-06121009).
>
> So, this patch introduces kvm_cpu_get_apicid() wrapper
> around __default_cpu_present_to_apicid() with additional
> handling if CONFIG_X86_LOCAL_APIC is not defined.
>
> Reported-by: kbuild test robot <fengguang.wu@xxxxxxxxx>
> Fixes: commit 8221c1370056 ("svm: Manage vcpu load/unload when enable AVIC")
> Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@xxxxxxx>
> ---
> arch/x86/include/asm/kvm_host.h | 11 +++++++++++
> arch/x86/kvm/svm.c | 6 +++---
> 2 files changed, 14 insertions(+), 3 deletions(-)
>
> diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
> index a714cc2..fe1c5c3 100644
> --- a/arch/x86/include/asm/kvm_host.h
> +++ b/arch/x86/include/asm/kvm_host.h
> @@ -27,6 +27,7 @@
> #include <linux/irqbypass.h>
> #include <linux/hyperv.h>
>
> +#include <asm/apic.h>
> #include <asm/pvclock-abi.h>
> #include <asm/desc.h>
> #include <asm/mtrr.h>
> @@ -1370,4 +1371,14 @@ static inline void kvm_arch_vcpu_unblocking(struct kvm_vcpu *vcpu)
>
> static inline void kvm_arch_vcpu_block_finish(struct kvm_vcpu *vcpu) {}
>
> +static inline int kvm_cpu_get_apicid(int mps_cpu)
> +{
> +#ifdef CONFIG_X86_LOCAL_APIC
> + return __default_cpu_present_to_apicid(mps_cpu);
> +#else
> + WARN_ON_ONCE(1);
> + return BAD_APICID;
> +#endif
> +}
> +
> #endif /* _ASM_X86_KVM_HOST_H */
> diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
> index 5b12438..0d2aa13 100644
> --- a/arch/x86/kvm/svm.c
> +++ b/arch/x86/kvm/svm.c
> @@ -1402,7 +1402,7 @@ avic_update_iommu(struct kvm_vcpu *vcpu, int cpu, phys_addr_t pa, bool r)
> static void avic_set_running(struct kvm_vcpu *vcpu, bool is_run)
> {
> u64 entry;
> - int h_physical_id = __default_cpu_present_to_apicid(vcpu->cpu);
> + int h_physical_id = kvm_cpu_get_apicid(vcpu->cpu);
> struct vcpu_svm *svm = to_svm(vcpu);
>
> if (!kvm_vcpu_apicv_active(vcpu))
> @@ -1434,7 +1434,7 @@ static void avic_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
> {
> u64 entry;
> /* ID = 0xff (broadcast), ID > 0xff (reserved) */
> - int h_physical_id = __default_cpu_present_to_apicid(cpu);
> + int h_physical_id = kvm_cpu_get_apicid(cpu);
> struct vcpu_svm *svm = to_svm(vcpu);
>
> if (!kvm_vcpu_apicv_active(vcpu))
> @@ -4328,7 +4328,7 @@ static void svm_deliver_avic_intr(struct kvm_vcpu *vcpu, int vec)
>
> if (avic_vcpu_is_running(vcpu))
> wrmsrl(SVM_AVIC_DOORBELL,
> - __default_cpu_present_to_apicid(vcpu->cpu));
> + kvm_cpu_get_apicid(vcpu->cpu));
> else
> kvm_vcpu_wake_up(vcpu);
> }
>