From mboxrd@z Thu Jan 1 00:00:00 1970 From: Wanpeng Li Subject: [PATCH v3 3/6] KVM: X86: Fallback to original apic hooks when bad happens Date: Tue, 3 Jul 2018 14:21:28 +0800 Message-ID: <1530598891-21370-4-git-send-email-wanpengli@tencent.com> References: <1530598891-21370-1-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?= , Vitaly Kuznetsov To: linux-kernel@vger.kernel.org, kvm@vger.kernel.org Return-path: In-Reply-To: <1530598891-21370-1-git-send-email-wanpengli@tencent.com> Sender: linux-kernel-owner@vger.kernel.org List-Id: kvm.vger.kernel.org From: Wanpeng Li Fallback to original apic hooks when apic id is sparse and larger than 128 or 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 | 26 +++++++++++++++++++------- 1 file changed, 19 insertions(+), 7 deletions(-) diff --git a/arch/x86/kernel/kvm.c b/arch/x86/kernel/kvm.c index 2fe1420..81be75b 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) @@ -456,13 +457,13 @@ static void __init sev_map_percpu_data(void) #ifdef CONFIG_SMP #ifdef CONFIG_X86_64 -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, ipi_bitmap_low = 0, ipi_bitmap_high = 0; - int cpu, apic_id; + int cpu, apic_id, ret = 0; if (cpumask_empty(mask)) - return; + return 0; local_irq_save(flags); @@ -472,16 +473,23 @@ static void __send_ipi_mask(const struct cpumask *mask, int vector) __set_bit(apic_id, &ipi_bitmap_low); else if (apic_id < 2 * BITS_PER_LONG) __set_bit(apic_id - BITS_PER_LONG, &ipi_bitmap_high); + else { + ret = -EFAULT; + goto irq_restore_exit; + } } - kvm_hypercall3(KVM_HC_SEND_IPI, ipi_bitmap_low, ipi_bitmap_high, vector); + ret = kvm_hypercall3(KVM_HC_SEND_IPI, ipi_bitmap_low, ipi_bitmap_high, vector); +irq_restore_exit: local_irq_restore(flags); + return ret; } static void kvm_send_ipi_mask(const struct cpumask *mask, int vector) { - __send_ipi_mask(mask, vector); + if (__send_ipi_mask(mask, vector)) + orig_apic.send_IPI_mask(mask, vector); } static void kvm_send_ipi_mask_allbutself(const struct cpumask *mask, int vector) @@ -493,7 +501,8 @@ 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) @@ -503,7 +512,8 @@ 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); } /* @@ -511,6 +521,8 @@ 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