From mboxrd@z Thu Jan 1 00:00:00 1970 From: Paolo Bonzini Subject: Re: [PATCH] KVM: x86: recalculate_apic_map after enabling apic Date: Tue, 19 Aug 2014 12:35:36 +0200 Message-ID: <53F32878.5050603@redhat.com> References: <1408395780-2307-1-git-send-email-namit@cs.technion.ac.il> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: kvm@vger.kernel.org To: Nadav Amit , gleb@kernel.org Return-path: Received: from mail-wg0-f43.google.com ([74.125.82.43]:45989 "EHLO mail-wg0-f43.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752226AbaHSKfl (ORCPT ); Tue, 19 Aug 2014 06:35:41 -0400 Received: by mail-wg0-f43.google.com with SMTP id l18so6135764wgh.2 for ; Tue, 19 Aug 2014 03:35:39 -0700 (PDT) In-Reply-To: <1408395780-2307-1-git-send-email-namit@cs.technion.ac.il> Sender: kvm-owner@vger.kernel.org List-ID: Il 18/08/2014 23:03, Nadav Amit ha scritto: > Currently, recalculate_apic_map ignores vcpus whose lapic is software disabled > through the spurious interrupt vector. However, once it is re-enabled, the map > is not recalculated. Therefore, if the guest OS configured DFR while lapic is > software-disabled, the map may be incorrect. This patch recalculates apic map > after software enabling the lapic. > > Signed-off-by: Nadav Amit > --- > arch/x86/kvm/lapic.c | 25 ++++++++++++++----------- > 1 file changed, 14 insertions(+), 11 deletions(-) > > diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c > index 08e8a89..4a736199 100644 > --- a/arch/x86/kvm/lapic.c > +++ b/arch/x86/kvm/lapic.c > @@ -112,17 +112,6 @@ static inline int __apic_test_and_clear_vector(int vec, void *bitmap) > struct static_key_deferred apic_hw_disabled __read_mostly; > struct static_key_deferred apic_sw_disabled __read_mostly; > > -static inline void apic_set_spiv(struct kvm_lapic *apic, u32 val) > -{ > - if ((kvm_apic_get_reg(apic, APIC_SPIV) ^ val) & APIC_SPIV_APIC_ENABLED) { > - if (val & APIC_SPIV_APIC_ENABLED) > - static_key_slow_dec_deferred(&apic_sw_disabled); > - else > - static_key_slow_inc(&apic_sw_disabled.key); > - } > - apic_set_reg(apic, APIC_SPIV, val); > -} > - > static inline int apic_enabled(struct kvm_lapic *apic) > { > return kvm_apic_sw_enabled(apic) && kvm_apic_hw_enabled(apic); > @@ -210,6 +199,20 @@ out: > kvm_vcpu_request_scan_ioapic(kvm); > } > > +static inline void apic_set_spiv(struct kvm_lapic *apic, u32 val) > +{ > + u32 prev = kvm_apic_get_reg(apic, APIC_SPIV); > + > + apic_set_reg(apic, APIC_SPIV, val); > + if ((prev ^ val) & APIC_SPIV_APIC_ENABLED) { > + if (val & APIC_SPIV_APIC_ENABLED) { > + static_key_slow_dec_deferred(&apic_sw_disabled); > + recalculate_apic_map(apic->vcpu->kvm); > + } else > + static_key_slow_inc(&apic_sw_disabled.key); > + } > +} > + > static inline void kvm_apic_set_id(struct kvm_lapic *apic, u8 id) > { > apic_set_reg(apic, APIC_ID, id << 24); > Applied to kvm/queue, thanks. Paolo