From mboxrd@z Thu Jan 1 00:00:00 1970 From: Wanpeng Li Subject: [PATCH v4 3/6] KVM: X86: Fallback to original apic hooks when bad happens Date: Sat, 21 Jul 2018 00:28:43 +0800 Message-ID: <1532104123-15727-1-git-send-email-wanpengli@tencent.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Cc: Paolo Bonzini , =?UTF-8?q?Radim=20Kr=C4=8Dm=C3=A1=C5=99?= , Wanpeng Li , Vitaly Kuznetsov To: linux-kernel@vger.kernel.org, kvm@vger.kernel.org Return-path: Sender: linux-kernel-owner@vger.kernel.org List-Id: kvm.vger.kernel.org From: Wanpeng Li Fallback to original apic hooks when unlikely kvm fails to add the pending IRQ to lapic. Cc: Paolo Bonzini Cc: Radim Krčmář Cc: Vitaly Kuznetsov Signed-off-by: Wanpeng Li --- arch/x86/kernel/kvm.c | 20 +++++++++++++------- 1 file changed, 13 insertions(+), 7 deletions(-) diff --git a/arch/x86/kernel/kvm.c b/arch/x86/kernel/kvm.c index eed6046..57eb4a2 100644 --- a/arch/x86/kernel/kvm.c +++ b/arch/x86/kernel/kvm.c @@ -47,6 +47,7 @@ #include #include +static struct apic orig_apic; static int kvmapf = 1; static int __init parse_no_kvmapf(char *arg) @@ -454,10 +455,10 @@ static void __init sev_map_percpu_data(void) } #ifdef CONFIG_SMP -static void __send_ipi_mask(const struct cpumask *mask, int vector) +static int __send_ipi_mask(const struct cpumask *mask, int vector) { unsigned long flags; - int cpu, apic_id, min = 0, max = 0; + int cpu, apic_id, min = 0, max = 0, ret = 0; #ifdef CONFIG_X86_64 __uint128_t ipi_bitmap = 0; int cluster_size = 128; @@ -467,7 +468,7 @@ static void __send_ipi_mask(const struct cpumask *mask, int vector) #endif if (cpumask_empty(mask)) - return; + return 0; local_irq_save(flags); @@ -481,7 +482,7 @@ static void __send_ipi_mask(const struct cpumask *mask, int vector) } else if (apic_id < min + cluster_size) { max = apic_id < max ? max : apic_id; } else { - kvm_hypercall4(KVM_HC_SEND_IPI, (unsigned long)ipi_bitmap, + ret = kvm_hypercall4(KVM_HC_SEND_IPI, (unsigned long)ipi_bitmap, (unsigned long)(ipi_bitmap >> BITS_PER_LONG), min, vector); min = max = apic_id; ipi_bitmap = 0; @@ -490,11 +491,12 @@ static void __send_ipi_mask(const struct cpumask *mask, int vector) } if (ipi_bitmap) { - kvm_hypercall4(KVM_HC_SEND_IPI, (unsigned long)ipi_bitmap, + ret = kvm_hypercall4(KVM_HC_SEND_IPI, (unsigned long)ipi_bitmap, (unsigned long)(ipi_bitmap >> BITS_PER_LONG), min, vector); } local_irq_restore(flags); + return ret; } static void kvm_send_ipi_mask(const struct cpumask *mask, int vector) @@ -511,7 +513,8 @@ static void kvm_send_ipi_mask_allbutself(const struct cpumask *mask, int vector) cpumask_copy(&new_mask, mask); cpumask_clear_cpu(this_cpu, &new_mask); local_mask = &new_mask; - __send_ipi_mask(local_mask, vector); + if (__send_ipi_mask(local_mask, vector)) + orig_apic.send_IPI_mask_allbutself(mask, vector); } static void kvm_send_ipi_allbutself(int vector) @@ -521,7 +524,8 @@ static void kvm_send_ipi_allbutself(int vector) static void kvm_send_ipi_all(int vector) { - __send_ipi_mask(cpu_online_mask, vector); + if (__send_ipi_mask(cpu_online_mask, vector)) + orig_apic.send_IPI_all(vector); } /* @@ -529,6 +533,8 @@ static void kvm_send_ipi_all(int vector) */ static void kvm_setup_pv_ipi(void) { + orig_apic = *apic; + apic->send_IPI_mask = kvm_send_ipi_mask; apic->send_IPI_mask_allbutself = kvm_send_ipi_mask_allbutself; apic->send_IPI_allbutself = kvm_send_ipi_allbutself; -- 2.7.4