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[2620:137:e000::1:20]) by mx.google.com with ESMTP id q4-20020aa7d444000000b0051e576dbb63si954162edr.534.2023.07.18.02.41.11; Tue, 18 Jul 2023 02:41:34 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20; Authentication-Results: mx.google.com; dkim=pass header.i=@redhat.com header.s=mimecast20190719 header.b=XuWIn0EF; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=redhat.com Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232131AbjGRJOV (ORCPT + 99 others); Tue, 18 Jul 2023 05:14:21 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53192 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230230AbjGRJOK (ORCPT ); Tue, 18 Jul 2023 05:14:10 -0400 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C837EE60 for ; Tue, 18 Jul 2023 02:13:22 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1689671602; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=4WlIkr5Df/8dGsk772CbAon6bnUBTqjKXV9qoX9zRiI=; b=XuWIn0EFCjTct5C0MhoQUZ8EgY/Cqus0cPO7OCBjJ4YZjZtK8EhrJBCoWifu5jRJufvjww KR2F1S8yFBmuAvg274kvv+53b1zv6cz9nRjybyq5UO2XRWS2Gb7bUCvTS/MunGlX/LUOzR a6j3z8FsyaPYdHAIiBPu4Ysbmok1tCI= Received: from mimecast-mx02.redhat.com (66.187.233.73 [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-14-dSfb6Q6kOYqqc21jhdQidA-1; Tue, 18 Jul 2023 05:13:18 -0400 X-MC-Unique: dSfb6Q6kOYqqc21jhdQidA-1 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.rdu2.redhat.com [10.11.54.7]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 685113803916; Tue, 18 Jul 2023 09:13:18 +0000 (UTC) Received: from localhost.localdomain (unknown [10.45.224.28]) by smtp.corp.redhat.com (Postfix) with ESMTP id ECCAC1454143; Tue, 18 Jul 2023 09:13:15 +0000 (UTC) From: Maxim Levitsky To: kvm@vger.kernel.org Cc: "H. Peter Anvin" , Sean Christopherson , linux-kernel@vger.kernel.org, Thomas Gleixner , Paolo Bonzini , Ingo Molnar , Dave Hansen , x86@kernel.org, Borislav Petkov , Maxim Levitsky Subject: [PATCH 1/3] KVM: x86: VMX: __kvm_apic_update_irr must update the IRR atomically Date: Tue, 18 Jul 2023 12:13:08 +0300 Message-Id: <20230718091310.119672-2-mlevitsk@redhat.com> In-Reply-To: <20230718091310.119672-1-mlevitsk@redhat.com> References: <20230718091310.119672-1-mlevitsk@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.1 on 10.11.54.7 X-Spam-Status: No, score=-2.1 required=5.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF, RCVD_IN_DNSWL_BLOCKED,RCVD_IN_MSPIKE_H4,RCVD_IN_MSPIKE_WL, SPF_HELO_NONE,SPF_NONE,T_SCC_BODY_TEXT_LINE autolearn=unavailable autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-THRID: 1771750864557575131 X-GMAIL-MSGID: 1771750864557575131 If APICv is inhibited, then IPIs from peer vCPUs are done by atomically setting bits in IRR. This means, that when __kvm_apic_update_irr copies PIR to IRR, it has to modify IRR atomically as well. Signed-off-by: Maxim Levitsky --- arch/x86/kvm/lapic.c | 18 +++++++++++------- 1 file changed, 11 insertions(+), 7 deletions(-) diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c index e542cf285b5184..b3f57e0f0d64ae 100644 --- a/arch/x86/kvm/lapic.c +++ b/arch/x86/kvm/lapic.c @@ -627,15 +627,19 @@ bool __kvm_apic_update_irr(u32 *pir, void *regs, int *max_irr) for (i = vec = 0; i <= 7; i++, vec += 32) { pir_val = READ_ONCE(pir[i]); - irr_val = *((u32 *)(regs + APIC_IRR + i * 0x10)); + irr_val = READ_ONCE(*((u32 *)(regs + APIC_IRR + i * 0x10))); + if (pir_val) { + pir_val = xchg(&pir[i], 0); + + while (!try_cmpxchg(((u32 *)(regs + APIC_IRR + i * 0x10)), + &irr_val, irr_val | pir_val)); + prev_irr_val = irr_val; - irr_val |= xchg(&pir[i], 0); - *((u32 *)(regs + APIC_IRR + i * 0x10)) = irr_val; - if (prev_irr_val != irr_val) { - max_updated_irr = - __fls(irr_val ^ prev_irr_val) + vec; - } + irr_val |= pir_val; + + if (prev_irr_val != irr_val) + max_updated_irr = __fls(irr_val ^ prev_irr_val) + vec; } if (irr_val) *max_irr = __fls(irr_val) + vec; From patchwork Tue Jul 18 09:13:09 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Maxim Levitsky X-Patchwork-Id: 121895 Return-Path: Delivered-To: ouuuleilei@gmail.com Received: by 2002:a59:c923:0:b0:3e4:2afc:c1 with SMTP id j3csp1611987vqt; Tue, 18 Jul 2023 02:23:00 -0700 (PDT) X-Google-Smtp-Source: APBJJlHAuSBtsY+G0aJBWNRLHolWyAQQgSjeY3FxkOp7s+7Y11WNanYajSCr0iYlGWEc87ePE+Ah X-Received: by 2002:a05:6402:2747:b0:51e:2c4b:6f1e with SMTP id z7-20020a056402274700b0051e2c4b6f1emr15140332edd.14.1689672180711; Tue, 18 Jul 2023 02:23:00 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1689672180; cv=none; d=google.com; s=arc-20160816; b=n7RhmHFhol0hCRLwjsOQaaN8HnOzGxDw0H6LziG+Ke3oO7wyJBxmrcvNNfoIxlMsy8 yTzj0vxYmontJrNm9Hj73WuzrGtoCGwgQXk9Fkwxj2EijKo6ZBFx5tfxcB/GwB0ZZjCV b0pDkSSow8xGOfe8rp3SnhaGz1An2+ppQuE562W/CmHCLYDYun04cB/CZ1Rypc6uJ2ue xmybdYEUxV8Fp6LTlPApwyYy6RPMkQUxPSc8vQECbOfIYM/eQvHR6K4FsD/uMJXszQg/ IJI6qgja6ECYhAnePfWmiI/0yX5k8BkblvIuenwq4NkU7D3rtcLKqUkqsvam2xZuxqUI x17Q== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:content-transfer-encoding:mime-version :references:in-reply-to:message-id:date:subject:cc:to:from :dkim-signature; bh=4C0D24d2FC1TYs50FyhHTmpHwv4hCv9vozKRBzYFkPk=; fh=h+09CC2YFXYXA44jAN2W/XszUAPEuokN58P13gOP3bQ=; b=RHm4Ww5kVNgMn649OfKteN/FHzxewro9Z+ziegVN9ZWiLd4pqOUcd1HvncfR7Ip5wb xIsjE3Xngl+oGeh8AKf/3/aqhNczlkhik9A2NNLHvJG9V4ScqblXbhprjufzoyJAdzny +6sGquPZhrRV28JNibAwJM97TcoIG9PWbO2e9q+Qc7eBNcX31DwARlNPpkW4YHUQv2FN 9B+hNw9gBjU6rRvDkWTQG0t1aJ7FtRlmhuhlkzAiT1VLNY0Ftxz+3YtTIrSYZncWpXL6 VCakFJ6Mi/n0AKQMKCm8LV0qIhbptPGp9QzxgZb2hQJhnucL5Amj9l8ScTNcp1FtBnes iYgg== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@redhat.com header.s=mimecast20190719 header.b="UwJ/38ko"; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=redhat.com Received: from out1.vger.email (out1.vger.email. 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Peter Anvin" , Sean Christopherson , linux-kernel@vger.kernel.org, Thomas Gleixner , Paolo Bonzini , Ingo Molnar , Dave Hansen , x86@kernel.org, Borislav Petkov , Maxim Levitsky Subject: [PATCH 2/3] KVM: x86: VMX: set irr_pending in kvm_apic_update_irr Date: Tue, 18 Jul 2023 12:13:09 +0300 Message-Id: <20230718091310.119672-3-mlevitsk@redhat.com> In-Reply-To: <20230718091310.119672-1-mlevitsk@redhat.com> References: <20230718091310.119672-1-mlevitsk@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.1 on 10.11.54.7 X-Spam-Status: No, score=-2.1 required=5.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF, RCVD_IN_DNSWL_BLOCKED,RCVD_IN_MSPIKE_H4,RCVD_IN_MSPIKE_WL, SPF_HELO_NONE,SPF_NONE,T_SCC_BODY_TEXT_LINE autolearn=unavailable autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-THRID: 1771749696105601877 X-GMAIL-MSGID: 1771749696105601877 When the APICv is inhibited, the irr_pending optimization is used. Therefore, when kvm_apic_update_irr sets bits in the IRR, it must set irr_pending to true as well. Signed-off-by: Maxim Levitsky --- arch/x86/kvm/lapic.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c index b3f57e0f0d64ae..613830ba2d8cef 100644 --- a/arch/x86/kvm/lapic.c +++ b/arch/x86/kvm/lapic.c @@ -653,8 +653,11 @@ EXPORT_SYMBOL_GPL(__kvm_apic_update_irr); bool kvm_apic_update_irr(struct kvm_vcpu *vcpu, u32 *pir, int *max_irr) { struct kvm_lapic *apic = vcpu->arch.apic; + bool irr_updated = __kvm_apic_update_irr(pir, apic->regs, max_irr); - return __kvm_apic_update_irr(pir, apic->regs, max_irr); + if (unlikely(!apic->apicv_active && irr_updated)) + apic->irr_pending = true; + return irr_updated; } EXPORT_SYMBOL_GPL(kvm_apic_update_irr); From patchwork Tue Jul 18 09:13:10 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Maxim Levitsky X-Patchwork-Id: 121914 Return-Path: Delivered-To: ouuuleilei@gmail.com Received: by 2002:a59:c923:0:b0:3e4:2afc:c1 with SMTP id j3csp1622926vqt; Tue, 18 Jul 2023 02:51:42 -0700 (PDT) X-Google-Smtp-Source: APBJJlGqdv8lb4lXGOuQtJS0fj8L9I1DY6L+n7DkzqfXs3dcdoLLf5VCcmJD7e9uDeasIBI0cyPQ X-Received: by 2002:a05:6358:4323:b0:134:c7ef:406d with SMTP id r35-20020a056358432300b00134c7ef406dmr10625155rwc.31.1689673902249; Tue, 18 Jul 2023 02:51:42 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1689673902; cv=none; d=google.com; s=arc-20160816; b=Ss8Dlq7gGQY6APfhVZookQLcl0f0HDWg2zn288KkdTWWF8aaOLLqtKB+hpEsNoVnOt cy3AR7xRdc+S4o3h3NtgMOY0+Z1ESXA2Z2Kr1Luw7r8Hziz9ImbtGX3G5LyJAWdXaKmd 8IjuihYWnbgQyjKs4q+qunBjzBibh3NczxFtLzK+I7sfw4Qn5y/dsDBif5c6UIIaaHfX QQEbHy3rNCPVeLBy/NTvO3+DfFCIsng6SKXltrLxVBB+6yPxIZnXltRKdYUZ2hMTM/RK 2DqqERKEK2aaqfvQtSxcVoSqSrmcgokqzaN91DZAUnu2a1PQ2Fu00V8g8vZHgjZSEpE8 d0wQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:content-transfer-encoding:mime-version :references:in-reply-to:message-id:date:subject:cc:to:from :dkim-signature; bh=i0Za5rKgUBZTxkAktgjwNM5+Kehhc/iwdSkhd6KTsmE=; fh=h+09CC2YFXYXA44jAN2W/XszUAPEuokN58P13gOP3bQ=; b=VMFB3taM3yESvYMYk/vgQM/HNdUuT/cJDHxg2tv3AgrNcsCblUQ5jFCODrdUegu9+w Hso+0Umg3feLAOopB2js0TFGDmJbWojLEyywRTgHcXNHI6xFHwxAi3gv0ZdX6qeiv+gz Bw4AMB04ChinIWUWOEVb6T6MsefiwUX96WlbWZDJQb1NdqGvnysICG/c77gVN5ef3P23 0rzBBX35AOusc1Fs4ImoLBra9oAWwlv+ltclGT1wxogW2CXwl/TJdK5Oz7ocLRCMpOfW wKrUATE1Wg9bw3bypQxmY7hVz/HLHxB4xln/tgQ+kgBPXFPaKPou3C28N6CtnKRxhKeF o45Q== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@redhat.com header.s=mimecast20190719 header.b=IG+OaGoV; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=redhat.com Received: from out1.vger.email (out1.vger.email. [2620:137:e000::1:20]) by mx.google.com with ESMTP id v16-20020a63d550000000b00543e36736d3si1322886pgi.628.2023.07.18.02.51.29; Tue, 18 Jul 2023 02:51:42 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20; Authentication-Results: mx.google.com; dkim=pass header.i=@redhat.com header.s=mimecast20190719 header.b=IG+OaGoV; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=redhat.com Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232185AbjGRJOd (ORCPT + 99 others); Tue, 18 Jul 2023 05:14:33 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53246 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232171AbjGRJOS (ORCPT ); Tue, 18 Jul 2023 05:14:18 -0400 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id BC322E5F for ; Tue, 18 Jul 2023 02:13:30 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1689671610; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=i0Za5rKgUBZTxkAktgjwNM5+Kehhc/iwdSkhd6KTsmE=; b=IG+OaGoVqM/d6IMrGhCO7lKJhP9aeVOl3tQ8IXHcr6mM0dleHtzlRaOK4Lv4EEqiKsl/pu p+iR9P52scHzWwJb3Mj+RO+XElxd/LnGbbiV/UtTFaBvE8BwdtgT1bTvARYja2z8Mt3TOL NMeFmjR2PbbG0VWeXBc2+F6bEl0Ycgw= Received: from mimecast-mx02.redhat.com (66.187.233.73 [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-611-q8j76lraNJGR3zgugEfZsA-1; Tue, 18 Jul 2023 05:13:24 -0400 X-MC-Unique: q8j76lraNJGR3zgugEfZsA-1 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.rdu2.redhat.com [10.11.54.7]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 12E972A59543; Tue, 18 Jul 2023 09:13:24 +0000 (UTC) Received: from localhost.localdomain (unknown [10.45.224.28]) by smtp.corp.redhat.com (Postfix) with ESMTP id 95ACD1454142; Tue, 18 Jul 2023 09:13:21 +0000 (UTC) From: Maxim Levitsky To: kvm@vger.kernel.org Cc: "H. Peter Anvin" , Sean Christopherson , linux-kernel@vger.kernel.org, Thomas Gleixner , Paolo Bonzini , Ingo Molnar , Dave Hansen , x86@kernel.org, Borislav Petkov , Maxim Levitsky Subject: [PATCH 3/3] KVM: x86: check the kvm_cpu_get_interrupt result before using it Date: Tue, 18 Jul 2023 12:13:10 +0300 Message-Id: <20230718091310.119672-4-mlevitsk@redhat.com> In-Reply-To: <20230718091310.119672-1-mlevitsk@redhat.com> References: <20230718091310.119672-1-mlevitsk@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.1 on 10.11.54.7 X-Spam-Status: No, score=-2.1 required=5.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF, RCVD_IN_DNSWL_BLOCKED,RCVD_IN_MSPIKE_H4,RCVD_IN_MSPIKE_WL, SPF_HELO_NONE,SPF_NONE,T_SCC_BODY_TEXT_LINE autolearn=unavailable autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-THRID: 1771751501875888717 X-GMAIL-MSGID: 1771751501875888717 The code was blindly assuming that kvm_cpu_get_interrupt never returns -1 when there is a pending interrupt. While this should be true, a bug in KVM can still cause this. If -1 is returned, the code before this patch was converting it to 0xFF, and 0xFF interrupt was injected to the guest, which results in an issue which was hard to debug. Add WARN_ON_ONCE to catch this case and skip the injection if this happens again. Signed-off-by: Maxim Levitsky --- arch/x86/kvm/x86.c | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-) diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index c0778ca39650f4..37162c589e8d0e 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -10190,9 +10190,13 @@ static int kvm_check_and_inject_events(struct kvm_vcpu *vcpu, if (r < 0) goto out; if (r) { - kvm_queue_interrupt(vcpu, kvm_cpu_get_interrupt(vcpu), false); - static_call(kvm_x86_inject_irq)(vcpu, false); - WARN_ON(static_call(kvm_x86_interrupt_allowed)(vcpu, true) < 0); + int irq = kvm_cpu_get_interrupt(vcpu); + + if (!WARN_ON_ONCE(irq == -1)) { + kvm_queue_interrupt(vcpu, irq, false); + static_call(kvm_x86_inject_irq)(vcpu, false); + WARN_ON(static_call(kvm_x86_interrupt_allowed)(vcpu, true) < 0); + } } if (kvm_cpu_has_injectable_intr(vcpu)) static_call(kvm_x86_enable_irq_window)(vcpu);