From patchwork Tue May 25 13:41:16 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Marcelo Tosatti X-Patchwork-Id: 12279067 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id A2C24C47084 for ; Tue, 25 May 2021 13:54:30 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 82A0761423 for ; Tue, 25 May 2021 13:54:30 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233373AbhEYNz6 (ORCPT ); Tue, 25 May 2021 09:55:58 -0400 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:40185 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233426AbhEYNzr (ORCPT ); Tue, 25 May 2021 09:55:47 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1621950857; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: references:references; bh=xrhUqBJUijGQwgB+DReNzr5ztKeOOykMqFsLk66ZLKY=; b=SbKPMTbYKt+9PsLzEbynwPah/UIWtG6cbITKegkWMtg5SYWMYPcrgJZqR1YILNvRRBzybQ h4FsI6OQyt1mejSxulER525GhOOW4iOJWQ2FDM6jBzhZn16Sp6V4dNnOmRTBC+EqEJtKTl dH4sIiF11rZlCYommX9azi8PPdpvFnU= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-267-MRm9T_1pP02Xb4YmpUoz_g-1; Tue, 25 May 2021 09:54:15 -0400 X-MC-Unique: MRm9T_1pP02Xb4YmpUoz_g-1 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 52EE0803622; Tue, 25 May 2021 13:54:14 +0000 (UTC) Received: from fuller.cnet (ovpn-112-2.gru2.redhat.com [10.97.112.2]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 2B59618B39; Tue, 25 May 2021 13:54:07 +0000 (UTC) Received: by fuller.cnet (Postfix, from userid 1000) id B2E9C4172EDB; Tue, 25 May 2021 10:44:35 -0300 (-03) Message-ID: <20210525134321.254128742@redhat.com> User-Agent: quilt/0.66 Date: Tue, 25 May 2021 10:41:16 -0300 From: Marcelo Tosatti To: kvm@vger.kernel.org Cc: Paolo Bonzini , Alex Williamson , Sean Christopherson , Peter Xu , Marcelo Tosatti Subject: [patch 1/3] KVM: x86: add start_assignment hook to kvm_x86_ops References: <20210525134115.135966361@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org Add a start_assignment hook to kvm_x86_ops, which is called when kvm_arch_start_assignment is done. The hook is required to update the wakeup vector of a sleeping vCPU when a device is assigned to the guest. Signed-off-by: Marcelo Tosatti Reviewed-by: Peter Xu Index: kvm/arch/x86/include/asm/kvm_host.h =================================================================== --- kvm.orig/arch/x86/include/asm/kvm_host.h +++ kvm/arch/x86/include/asm/kvm_host.h @@ -1322,6 +1322,7 @@ struct kvm_x86_ops { int (*update_pi_irte)(struct kvm *kvm, unsigned int host_irq, uint32_t guest_irq, bool set); + void (*start_assignment)(struct kvm *kvm); void (*apicv_post_state_restore)(struct kvm_vcpu *vcpu); bool (*dy_apicv_has_pending_interrupt)(struct kvm_vcpu *vcpu); Index: kvm/arch/x86/kvm/x86.c =================================================================== --- kvm.orig/arch/x86/kvm/x86.c +++ kvm/arch/x86/kvm/x86.c @@ -11295,7 +11295,8 @@ bool kvm_arch_can_dequeue_async_page_pre void kvm_arch_start_assignment(struct kvm *kvm) { - atomic_inc(&kvm->arch.assigned_device_count); + if (atomic_inc_return(&kvm->arch.assigned_device_count) == 1) + static_call_cond(kvm_x86_start_assignment)(kvm); } EXPORT_SYMBOL_GPL(kvm_arch_start_assignment); Index: kvm/arch/x86/include/asm/kvm-x86-ops.h =================================================================== --- kvm.orig/arch/x86/include/asm/kvm-x86-ops.h +++ kvm/arch/x86/include/asm/kvm-x86-ops.h @@ -99,6 +99,7 @@ KVM_X86_OP_NULL(post_block) KVM_X86_OP_NULL(vcpu_blocking) KVM_X86_OP_NULL(vcpu_unblocking) KVM_X86_OP_NULL(update_pi_irte) +KVM_X86_OP_NULL(start_assignment) KVM_X86_OP_NULL(apicv_post_state_restore) KVM_X86_OP_NULL(dy_apicv_has_pending_interrupt) KVM_X86_OP_NULL(set_hv_timer) From patchwork Tue May 25 13:41:17 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Marcelo Tosatti X-Patchwork-Id: 12279071 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6638AC2B9F8 for ; Tue, 25 May 2021 13:54:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 44F0661420 for ; Tue, 25 May 2021 13:54:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233468AbhEYN4D (ORCPT ); Tue, 25 May 2021 09:56:03 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:54096 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233380AbhEYNz4 (ORCPT ); Tue, 25 May 2021 09:55:56 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1621950865; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: references:references; bh=gOuDbl0+VRR8LPwx8tZdmeXgGsQE7zoWmnV3C2G7mxU=; b=LnB2KBpK8c1eN5PNkH7vMhDoL2v8ebK2MKfNssjG31WskDkW4gIWdAMGNy5X21BVKOVNBn geUKGfj/2IMZyIANI5Z8mLxdPQAmyDwZ7esC+A9AB67J0qmpljmvh/ZAvo+XtRh+4Zsaqx 4NRvvOxo6jiY88Wc57F9Jc2mt0uwVVA= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-378-Jj8Ku6JYNjODYHDQ7nHDVQ-1; Tue, 25 May 2021 09:54:21 -0400 X-MC-Unique: Jj8Ku6JYNjODYHDQ7nHDVQ-1 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id CCC14501E0; Tue, 25 May 2021 13:54:20 +0000 (UTC) Received: from fuller.cnet (ovpn-112-2.gru2.redhat.com [10.97.112.2]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 2B4F1421F; Tue, 25 May 2021 13:54:07 +0000 (UTC) Received: by fuller.cnet (Postfix, from userid 1000) id B3FDC4172EDE; Tue, 25 May 2021 10:44:35 -0300 (-03) Message-ID: <20210525134321.303768132@redhat.com> User-Agent: quilt/0.66 Date: Tue, 25 May 2021 10:41:17 -0300 From: Marcelo Tosatti To: kvm@vger.kernel.org Cc: Paolo Bonzini , Alex Williamson , Sean Christopherson , Peter Xu , Marcelo Tosatti Subject: [patch 2/3] KVM: rename KVM_REQ_PENDING_TIMER to KVM_REQ_UNBLOCK References: <20210525134115.135966361@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org KVM_REQ_UNBLOCK will be used to exit a vcpu from its inner vcpu halt emulation loop. Rename KVM_REQ_PENDING_TIMER to KVM_REQ_UNBLOCK, switch PowerPC to arch specific request bit. Signed-off-by: Marcelo Tosatti Reviewed-by: Peter Xu Index: kvm/include/linux/kvm_host.h =================================================================== --- kvm.orig/include/linux/kvm_host.h +++ kvm/include/linux/kvm_host.h @@ -146,7 +146,7 @@ static inline bool is_error_page(struct */ #define KVM_REQ_TLB_FLUSH (0 | KVM_REQUEST_WAIT | KVM_REQUEST_NO_WAKEUP) #define KVM_REQ_MMU_RELOAD (1 | KVM_REQUEST_WAIT | KVM_REQUEST_NO_WAKEUP) -#define KVM_REQ_PENDING_TIMER 2 +#define KVM_REQ_UNBLOCK 2 #define KVM_REQ_UNHALT 3 #define KVM_REQUEST_ARCH_BASE 8 Index: kvm/virt/kvm/kvm_main.c =================================================================== --- kvm.orig/virt/kvm/kvm_main.c +++ kvm/virt/kvm/kvm_main.c @@ -2794,6 +2794,8 @@ static int kvm_vcpu_check_block(struct k goto out; if (signal_pending(current)) goto out; + if (kvm_check_request(KVM_REQ_UNBLOCK, vcpu)) + goto out; ret = 0; out: Index: kvm/Documentation/virt/kvm/vcpu-requests.rst =================================================================== --- kvm.orig/Documentation/virt/kvm/vcpu-requests.rst +++ kvm/Documentation/virt/kvm/vcpu-requests.rst @@ -118,10 +118,11 @@ KVM_REQ_MMU_RELOAD necessary to inform each VCPU to completely refresh the tables. This request is used for that. -KVM_REQ_PENDING_TIMER +KVM_REQ_UNBLOCK This request may be made from a timer handler run on the host on behalf - of a VCPU. It informs the VCPU thread to inject a timer interrupt. + of a VCPU, or when device assignment is performed. It informs the VCPU to + exit the vcpu halt inner loop. KVM_REQ_UNHALT Index: kvm/arch/powerpc/include/asm/kvm_host.h =================================================================== --- kvm.orig/arch/powerpc/include/asm/kvm_host.h +++ kvm/arch/powerpc/include/asm/kvm_host.h @@ -51,6 +51,7 @@ /* PPC-specific vcpu->requests bit members */ #define KVM_REQ_WATCHDOG KVM_ARCH_REQ(0) #define KVM_REQ_EPR_EXIT KVM_ARCH_REQ(1) +#define KVM_REQ_PENDING_TIMER KVM_ARCH_REQ(2) #include Index: kvm/arch/x86/kvm/lapic.c =================================================================== --- kvm.orig/arch/x86/kvm/lapic.c +++ kvm/arch/x86/kvm/lapic.c @@ -1657,7 +1657,7 @@ static void apic_timer_expired(struct kv } atomic_inc(&apic->lapic_timer.pending); - kvm_make_request(KVM_REQ_PENDING_TIMER, vcpu); + kvm_make_request(KVM_REQ_UNBLOCK, vcpu); if (from_timer_fn) kvm_vcpu_kick(vcpu); } Index: kvm/arch/x86/kvm/x86.c =================================================================== --- kvm.orig/arch/x86/kvm/x86.c +++ kvm/arch/x86/kvm/x86.c @@ -9300,7 +9300,7 @@ static int vcpu_run(struct kvm_vcpu *vcp if (r <= 0) break; - kvm_clear_request(KVM_REQ_PENDING_TIMER, vcpu); + kvm_clear_request(KVM_REQ_UNBLOCK, vcpu); if (kvm_cpu_has_pending_timer(vcpu)) kvm_inject_pending_timer_irqs(vcpu); From patchwork Tue May 25 13:41:18 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Marcelo Tosatti X-Patchwork-Id: 12279065 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1D1DEC2B9F8 for ; Tue, 25 May 2021 13:54:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E924A61423 for ; Tue, 25 May 2021 13:54:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233417AbhEYNz5 (ORCPT ); Tue, 25 May 2021 09:55:57 -0400 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:45799 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233385AbhEYNzq (ORCPT ); Tue, 25 May 2021 09:55:46 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1621950856; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: references:references; bh=NPGYHoSnoFBe2Pyrr6tNPxDx3Mmjq4+YFrgUxsImBrY=; b=W1yOw9Es6U6bZhHrbK/MTb4lPyNysB9j/q20X37ji7MEHMtjACpZvctjvg91FVWGftu5WT ZZt2pmpundAr+L69mWQ6rvAe3I1HLX8qmoyNUJ+IgNgYm3TjWrcSlfTdFlzP4x8kuBdZJR cReVCbMQkU7cP4I8uQGOHYp6qN4PY3E= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-551-L5hCDacVMDW_Knrk1BCamQ-1; Tue, 25 May 2021 09:54:15 -0400 X-MC-Unique: L5hCDacVMDW_Knrk1BCamQ-1 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 56464501E3; Tue, 25 May 2021 13:54:14 +0000 (UTC) Received: from fuller.cnet (ovpn-112-2.gru2.redhat.com [10.97.112.2]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 2B6B761094; Tue, 25 May 2021 13:54:07 +0000 (UTC) Received: by fuller.cnet (Postfix, from userid 1000) id B50D54179BB2; Tue, 25 May 2021 10:44:35 -0300 (-03) Message-ID: <20210525134321.345140341@redhat.com> User-Agent: quilt/0.66 Date: Tue, 25 May 2021 10:41:18 -0300 From: Marcelo Tosatti To: kvm@vger.kernel.org Cc: Paolo Bonzini , Alex Williamson , Sean Christopherson , Peter Xu , Pei Zhang , Marcelo Tosatti Subject: [patch 3/3] KVM: VMX: update vcpu posted-interrupt descriptor when assigning device References: <20210525134115.135966361@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org For VMX, when a vcpu enters HLT emulation, pi_post_block will: 1) Add vcpu to per-cpu list of blocked vcpus. 2) Program the posted-interrupt descriptor "notification vector" to POSTED_INTR_WAKEUP_VECTOR With interrupt remapping, an interrupt will set the PIR bit for the vector programmed for the device on the CPU, test-and-set the ON bit on the posted interrupt descriptor, and if the ON bit is clear generate an interrupt for the notification vector. This way, the target CPU wakes upon a device interrupt and wakes up the target vcpu. Problem is that pi_post_block only programs the notification vector if kvm_arch_has_assigned_device() is true. Its possible for the following to happen: 1) vcpu V HLTs on pcpu P, kvm_arch_has_assigned_device is false, notification vector is not programmed 2) device is assigned to VM 3) device interrupts vcpu V, sets ON bit (notification vector not programmed, so pcpu P remains in idle) 4) vcpu 0 IPIs vcpu V (in guest), but since pi descriptor ON bit is set, kvm_vcpu_kick is skipped 5) vcpu 0 busy spins on vcpu V's response for several seconds, until RCU watchdog NMIs all vCPUs. To fix this, use the start_assignment kvm_x86_ops callback to kick vcpus out of the halt loop, so the notification vector is properly reprogrammed to the wakeup vector. Reported-by: Pei Zhang Signed-off-by: Marcelo Tosatti Reviewed-by: Peter Xu Reported-by: kernel test robot Index: kvm/arch/x86/kvm/vmx/posted_intr.c =================================================================== --- kvm.orig/arch/x86/kvm/vmx/posted_intr.c +++ kvm/arch/x86/kvm/vmx/posted_intr.c @@ -236,6 +236,13 @@ bool pi_has_pending_interrupt(struct kvm (pi_test_sn(pi_desc) && !pi_is_pir_empty(pi_desc)); } +void vmx_pi_start_assignment(struct kvm *kvm) +{ + if (!irq_remapping_cap(IRQ_POSTING_CAP)) + return; + + kvm_make_all_cpus_request(kvm, KVM_REQ_UNBLOCK); +} /* * pi_update_irte - set IRTE for Posted-Interrupts Index: kvm/arch/x86/kvm/vmx/posted_intr.h =================================================================== --- kvm.orig/arch/x86/kvm/vmx/posted_intr.h +++ kvm/arch/x86/kvm/vmx/posted_intr.h @@ -95,5 +95,6 @@ void __init pi_init_cpu(int cpu); bool pi_has_pending_interrupt(struct kvm_vcpu *vcpu); int pi_update_irte(struct kvm *kvm, unsigned int host_irq, uint32_t guest_irq, bool set); +void vmx_pi_start_assignment(struct kvm *kvm); #endif /* __KVM_X86_VMX_POSTED_INTR_H */ Index: kvm/arch/x86/kvm/vmx/vmx.c =================================================================== --- kvm.orig/arch/x86/kvm/vmx/vmx.c +++ kvm/arch/x86/kvm/vmx/vmx.c @@ -7732,6 +7732,7 @@ static struct kvm_x86_ops vmx_x86_ops __ .nested_ops = &vmx_nested_ops, .update_pi_irte = pi_update_irte, + .start_assignment = vmx_pi_start_assignment, #ifdef CONFIG_X86_64 .set_hv_timer = vmx_set_hv_timer,