From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758073AbbA2Vtn (ORCPT ); Thu, 29 Jan 2015 16:49:43 -0500 Received: from mx1.redhat.com ([209.132.183.28]:40867 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758463AbbA2Vtk (ORCPT ); Thu, 29 Jan 2015 16:49:40 -0500 From: =?UTF-8?q?Radim=20Kr=C4=8Dm=C3=A1=C5=99?= To: linux-kernel@vger.kernel.org Cc: kvm@vger.kernel.org, Paolo Bonzini , Nadav Amit , Gleb Natapov Subject: [PATCH 5/8] KVM: x86: use MDA for interrupt matching Date: Thu, 29 Jan 2015 22:48:52 +0100 Message-Id: <1422568135-28402-6-git-send-email-rkrcmar@redhat.com> In-Reply-To: <1422568135-28402-1-git-send-email-rkrcmar@redhat.com> References: <1422568135-28402-1-git-send-email-rkrcmar@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org In mixed modes, we musn't deliver xAPIC IPIs like x2APIC and vice versa. Instead of preserving the information in apic_send_ipi(), we regain it by converting all destinations into correct APIC MDA in the slow path. This allows easier reasoning about subsequent matching. kvm_apic_broadcast() had an interesting design decision: it didn't consider IOxAPIC 0xff as broadcast in x2APIC mode ... everything worked because IOxAPIC can't set that in physical mode and logical mode considered it as a message for first 8 VCPUs. This patch interprets IOxAPIC 0xff as x2APIC broadcast. Signed-off-by: Radim Krčmář --- arch/x86/kvm/lapic.c | 40 +++++++++++++++++++++++++++++++++------- 1 file changed, 33 insertions(+), 7 deletions(-) diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c index aae043f38548..871ce6a2485b 100644 --- a/arch/x86/kvm/lapic.c +++ b/arch/x86/kvm/lapic.c @@ -581,15 +581,24 @@ static void apic_set_tpr(struct kvm_lapic *apic, u32 tpr) apic_update_ppr(apic); } -static bool kvm_apic_broadcast(struct kvm_lapic *apic, u32 dest) +static bool kvm_apic_broadcast(struct kvm_lapic *apic, u32 mda) { - return dest == (apic_x2apic_mode(apic) ? - X2APIC_BROADCAST : APIC_BROADCAST); + if (apic_x2apic_mode(apic)) + return mda == X2APIC_BROADCAST; + + /* XXX: verify that xAPIC accepts x2APIC broadcast */ + return GET_APIC_DEST_FIELD(mda) == APIC_BROADCAST; } -static bool kvm_apic_match_physical_addr(struct kvm_lapic *apic, u32 dest) +static bool kvm_apic_match_physical_addr(struct kvm_lapic *apic, u32 mda) { - return kvm_apic_id(apic) == dest || kvm_apic_broadcast(apic, dest); + if (kvm_apic_broadcast(apic, mda)) + return true; + + if (apic_x2apic_mode(apic)) + return mda == kvm_apic_id(apic); + + return mda == SET_APIC_DEST_FIELD(kvm_apic_id(apic)); } static bool kvm_apic_match_logical_addr(struct kvm_lapic *apic, u32 mda) @@ -606,6 +615,7 @@ static bool kvm_apic_match_logical_addr(struct kvm_lapic *apic, u32 mda) && (logical_id & mda & 0xffff); logical_id = GET_APIC_LOGICAL_ID(logical_id); + mda = GET_APIC_DEST_FIELD(mda); switch (kvm_apic_get_reg(apic, APIC_DFR)) { case APIC_DFR_FLAT: @@ -620,10 +630,26 @@ static bool kvm_apic_match_logical_addr(struct kvm_lapic *apic, u32 mda) } } +/* KVM APIC implementation has two quirks + * - dest always begins at 0 while xAPIC MDA has offset 24, + * - IOxAPIC messages have to be delivered (directly) to x2APIC. + */ +static u32 +kvm_apic_mda(unsigned int dest, struct kvm_lapic *ipi, bool x2apic_dest) +{ + bool x2apic_mda = ipi ? apic_x2apic_mode(ipi) : x2apic_dest; + + if (!ipi && dest == APIC_BROADCAST) + dest = X2APIC_BROADCAST; + + return x2apic_mda ? dest : SET_APIC_DEST_FIELD(dest); +} + bool kvm_apic_match_dest(struct kvm_vcpu *vcpu, struct kvm_lapic *source, int short_hand, unsigned int dest, int dest_mode) { struct kvm_lapic *target = vcpu->arch.apic; + u32 mda = kvm_apic_mda(dest, source, apic_x2apic_mode(target)); apic_debug("target %p, source %p, dest 0x%x, " "dest_mode 0x%x, short_hand 0x%x\n", @@ -633,9 +659,9 @@ bool kvm_apic_match_dest(struct kvm_vcpu *vcpu, struct kvm_lapic *source, switch (short_hand) { case APIC_DEST_NOSHORT: if (dest_mode == APIC_DEST_PHYSICAL) - return kvm_apic_match_physical_addr(target, dest); + return kvm_apic_match_physical_addr(target, mda); else - return kvm_apic_match_logical_addr(target, dest); + return kvm_apic_match_logical_addr(target, mda); case APIC_DEST_SELF: return target == source; case APIC_DEST_ALLINC: -- 2.2.2