Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1161170AbcLPRH1 (ORCPT ); Fri, 16 Dec 2016 12:07:27 -0500 Received: from mx1.redhat.com ([209.132.183.28]:42886 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752922AbcLPRHP (ORCPT ); Fri, 16 Dec 2016 12:07:15 -0500 Date: Fri, 16 Dec 2016 18:07:10 +0100 From: Radim =?utf-8?B?S3LEjW3DocWZ?= To: Paolo Bonzini Cc: David Hildenbrand , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, Igor Mammedov Subject: [PATCH v4 3/4] KVM: x86: make interrupt delivery fast and slow path behave the same Message-ID: <20161216170710.GB3637@potion> References: <20161215170648.15714-1-rkrcmar@redhat.com> <20161215170648.15714-4-rkrcmar@redhat.com> <34c85540-653c-5a83-0f3b-1ce1c8580751@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <34c85540-653c-5a83-0f3b-1ce1c8580751@redhat.com> X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.27]); Fri, 16 Dec 2016 17:07:14 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3242 Lines: 89 2016-12-16 17:53+0100, Paolo Bonzini: > On 16/12/2016 17:41, David Hildenbrand wrote: >> >> Just to verify: >> >> The GET_APIC_DEST_FIELD(mda) == APIC_BROADCAST is still correct in >> kvm_apic_broadcast() ? > > No, it seems wrong. Definitely, sending v4 of this patch. I'll also add broadcast address check into kvm-unit-tests ... ---8<--- Slow path tried to prevent IPIs from x2APIC VCPUs from being delivered to xAPIC VCPUs and vice-versa. Make slow path behave like fast path, which never distinguished that. Signed-off-by: Radim Krčmář --- v4: fix xAPIC broadcast address detection [David] --- arch/x86/kvm/lapic.c | 20 ++++++++------------ 1 file changed, 8 insertions(+), 12 deletions(-) diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c index 81cc93580c40..dba19cb82c3e 100644 --- a/arch/x86/kvm/lapic.c +++ b/arch/x86/kvm/lapic.c @@ -592,10 +592,8 @@ static void apic_set_tpr(struct kvm_lapic *apic, u32 tpr) static bool kvm_apic_broadcast(struct kvm_lapic *apic, u32 mda) { - if (apic_x2apic_mode(apic)) - return mda == X2APIC_BROADCAST; - - return GET_APIC_DEST_FIELD(mda) == APIC_BROADCAST; + return mda == (apic_x2apic_mode(apic) ? + X2APIC_BROADCAST : APIC_BROADCAST); } static bool kvm_apic_match_physical_addr(struct kvm_lapic *apic, u32 mda) @@ -606,7 +604,7 @@ static bool kvm_apic_match_physical_addr(struct kvm_lapic *apic, u32 mda) if (apic_x2apic_mode(apic)) return mda == kvm_x2apic_id(apic); - return mda == SET_APIC_DEST_FIELD(kvm_xapic_id(apic)); + return mda == kvm_xapic_id(apic); } static bool kvm_apic_match_logical_addr(struct kvm_lapic *apic, u32 mda) @@ -623,7 +621,6 @@ static bool kvm_apic_match_logical_addr(struct kvm_lapic *apic, u32 mda) && (logical_id & mda & 0xffff) != 0; logical_id = GET_APIC_LOGICAL_ID(logical_id); - mda = GET_APIC_DEST_FIELD(mda); switch (kvm_lapic_get_reg(apic, APIC_DFR)) { case APIC_DFR_FLAT: @@ -640,9 +637,9 @@ static bool kvm_apic_match_logical_addr(struct kvm_lapic *apic, u32 mda) /* The KVM local APIC implementation has two quirks: * - * - the xAPIC MDA stores the destination at bits 24-31, while this - * is not true of struct kvm_lapic_irq's dest_id field. This is - * just a quirk in the API and is not problematic. + * - Real hardware delivers interrupts destined to x2APIC ID > 0xff to LAPICs + * in xAPIC mode if the "destination & 0xff" matches its xAPIC ID. + * KVM doesn't do that aliasing. * * - in-kernel IOAPIC messages have to be delivered directly to * x2APIC, because the kernel does not support interrupt remapping. @@ -658,13 +655,12 @@ static u32 kvm_apic_mda(struct kvm_vcpu *vcpu, unsigned int dest_id, struct kvm_lapic *source, struct kvm_lapic *target) { bool ipi = source != NULL; - bool x2apic_mda = apic_x2apic_mode(ipi ? source : target); if (!vcpu->kvm->arch.x2apic_broadcast_quirk_disabled && - !ipi && dest_id == APIC_BROADCAST && x2apic_mda) + !ipi && dest_id == APIC_BROADCAST && apic_x2apic_mode(target)) return X2APIC_BROADCAST; - return x2apic_mda ? dest_id : SET_APIC_DEST_FIELD(dest_id); + return dest_id; } bool kvm_apic_match_dest(struct kvm_vcpu *vcpu, struct kvm_lapic *source, -- 2.11.0