From patchwork Fri Apr 4 19:39:01 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sean Christopherson X-Patchwork-Id: 14038868 Received: from mail-pf1-f201.google.com (mail-pf1-f201.google.com [209.85.210.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id D55C423BD1C for ; Fri, 4 Apr 2025 19:41:06 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.210.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1743795668; cv=none; b=tPggezw+jGN8AdzYsH8U+NFFWNm58hwuOmXvQBP7Vp7MLAgumJqLOWadOAVMsPf90/rgVCPczf2Up1mNI0f0Pvry8BF2DJqh40b6yoykcI6Uy6obbjsJvn8Ze9saZX/7B6cCQFfwgBGdtS2XlElalL5fu/+ucySL+AoI4W8xPrI= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1743795668; c=relaxed/simple; bh=vEYwD1yOWLfk/95pT3cNRoQCpvLsFYMJf/mNwwjdg6w=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=gaDUQt6j6E6trvYpmyxsJssYM9SaPfzCjifpZZfaUMgi5/qq3fyS1cSeMUCRtUtVAFofZLb4CdH5fN6brT6FtWkF4rNjiGb1MsML+qMoi/hfgfwKPudUmpc2qyfIsvYPpd4+JmNg6FrpJcmYvETryc80uBfVoiwCTShKR83yxeA= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--seanjc.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=RHIN6lgr; arc=none smtp.client-ip=209.85.210.201 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--seanjc.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="RHIN6lgr" Received: by mail-pf1-f201.google.com with SMTP id d2e1a72fcca58-736b2a25d9fso1983611b3a.0 for ; Fri, 04 Apr 2025 12:41:06 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1743795666; x=1744400466; darn=vger.kernel.org; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:reply-to:from:to:cc:subject:date:message-id:reply-to; bh=fCu4znq/izmNOP+TGp2LQJl6nRBB96ndlJ2G/FSp1oU=; b=RHIN6lgrIfeFHt2loEhTGwv5J4IOocqS1BmpajAT2NECGOQJECqTISX1590E8yip8y Q7FJBWXqk+Klh4YbzjW0ifdmcbVy/jAoAAtNySD//zHoG7mEkNMi65zgaYwc5q/0nwOg M+atOXn7V3czvZVSCZKJu0m7LRYkC1JISB1iup9xal/w7D17iTvrKZxAsWHqyD726DBp 3q0uqpkaoLjCH+l0BoupCJNdR64mnZ+q1qxDK7GAmgIR1tM69uVYpBqUULD1OL/06QZr ycez5fCeCpZhklAlcI85JAhsINKtMIx5zqikI14fzXysh6yznuVY9Vk3UYSL2JFs5lqI wCnA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1743795666; x=1744400466; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:reply-to:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=fCu4znq/izmNOP+TGp2LQJl6nRBB96ndlJ2G/FSp1oU=; b=e8Qm4hac6uCqMkl9/FLEQ8wqUDCei5bIfNqs216au9GVX0TuR56f90YKGkH7nCk9mJ /03D0Ez9Y6xUaUsJqP88HfjxgRZFW665SfcTHc2UBuXtmOOqgV4VrXbj2cWF+QgoL+km V4EcHNeduvOE8myC1G762/Q+p7JgAXKq8tYnyUEOp50ahXCqaPGP78yOXB/keRSi7BwG beiW7lNXkAHYjWbGtBtPllTT7NfzBHKJ8YXJptRv5W+/y+z3zOnzQxOX/U58MjVW0sav RRD49uLCSst8xxZbRJUHnw3bvpqf2razDw/mvO3pwjq5O1OZ85TF8MlYqQQMa1eJWMF8 C2uw== X-Gm-Message-State: AOJu0Yw1HMEGlVa7Z6MP4+QKYzWSzXwa7qCe4HEetGJ7of+VRiaOdjYe 3nEndkY5sXdzkNgu7wrOkVk4fakk2TE/sWlGmuuuCSz+ky2kC927ot4afokVMJVJRr1RdYDs+JW DrQ== X-Google-Smtp-Source: AGHT+IGPj22UXTH/Zcy5qZIqn9/BjQASYjiq8B8h2ade9XrhvSEXkbVGkfxvkxUFnqdy7NHyCw+NgEfc9co= X-Received: from pfch7.prod.google.com ([2002:a05:6a00:1707:b0:736:aaee:120e]) (user=seanjc job=prod-delivery.src-stubby-dispatcher) by 2002:a05:6a00:3cc2:b0:730:75b1:7219 with SMTP id d2e1a72fcca58-739e70575e6mr4840675b3a.12.1743795666219; Fri, 04 Apr 2025 12:41:06 -0700 (PDT) Reply-To: Sean Christopherson Date: Fri, 4 Apr 2025 12:39:01 -0700 In-Reply-To: <20250404193923.1413163-1-seanjc@google.com> Precedence: bulk X-Mailing-List: kvm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20250404193923.1413163-1-seanjc@google.com> X-Mailer: git-send-email 2.49.0.504.g3bcea36a83-goog Message-ID: <20250404193923.1413163-47-seanjc@google.com> Subject: [PATCH 46/67] iommu/amd: KVM: SVM: Set pCPU info in IRTE when setting vCPU affinity From: Sean Christopherson To: Sean Christopherson , Paolo Bonzini , Joerg Roedel , David Woodhouse , Lu Baolu Cc: kvm@vger.kernel.org, iommu@lists.linux.dev, linux-kernel@vger.kernel.org, Maxim Levitsky , Joao Martins , David Matlack Now that setting vCPU affinity is guarded with ir_list_lock, i.e. now that avic_physical_id_entry can be safely accessed, set the pCPU info straight-away when setting vCPU affinity. Putting the IRTE into posted mode, and then immediately updating the IRTE a second time if the target vCPU is running is wasteful and confusing. This also fixes a flaw where a posted IRQ that arrives between putting the IRTE into guest_mode and setting the correct destination could cause the IOMMU to ring the doorbell on the wrong pCPU. Signed-off-by: Sean Christopherson --- arch/x86/include/asm/irq_remapping.h | 1 + arch/x86/kvm/svm/avic.c | 26 ++++++++++++++------------ drivers/iommu/amd/iommu.c | 6 ++++-- include/linux/amd-iommu.h | 4 ++-- 4 files changed, 21 insertions(+), 16 deletions(-) diff --git a/arch/x86/include/asm/irq_remapping.h b/arch/x86/include/asm/irq_remapping.h index 2dbc9cb61c2f..4c75a17632f6 100644 --- a/arch/x86/include/asm/irq_remapping.h +++ b/arch/x86/include/asm/irq_remapping.h @@ -35,6 +35,7 @@ struct amd_iommu_pi_data { u64 vapic_addr; /* Physical address of the vCPU's vAPIC. */ u32 ga_tag; u32 vector; /* Guest vector of the interrupt */ + int cpu; bool is_guest_mode; void *ir_data; }; diff --git a/arch/x86/kvm/svm/avic.c b/arch/x86/kvm/svm/avic.c index 3fcec297e3e3..086139e85242 100644 --- a/arch/x86/kvm/svm/avic.c +++ b/arch/x86/kvm/svm/avic.c @@ -735,6 +735,7 @@ void avic_apicv_post_state_restore(struct kvm_vcpu *vcpu) static int avic_set_pi_irte_mode(struct kvm_vcpu *vcpu, bool activate) { + int apic_id = kvm_cpu_get_apicid(vcpu->cpu); int ret = 0; unsigned long flags; struct amd_svm_iommu_ir *ir; @@ -754,7 +755,7 @@ static int avic_set_pi_irte_mode(struct kvm_vcpu *vcpu, bool activate) list_for_each_entry(ir, &svm->ir_list, node) { if (activate) - ret = amd_iommu_activate_guest_mode(ir->data); + ret = amd_iommu_activate_guest_mode(ir->data, apic_id); else ret = amd_iommu_deactivate_guest_mode(ir->data); if (ret) @@ -819,6 +820,18 @@ int avic_pi_update_irte(struct kvm_kernel_irqfd *irqfd, struct kvm *kvm, */ guard(spinlock_irqsave)(&svm->ir_list_lock); + /* + * Update the target pCPU for IOMMU doorbells if the vCPU is + * running. If the vCPU is NOT running, i.e. is blocking or + * scheduled out, KVM will update the pCPU info when the vCPU + * is awakened and/or scheduled in. See also avic_vcpu_load(). + */ + entry = svm->avic_physical_id_entry; + if (entry & AVIC_PHYSICAL_ID_ENTRY_IS_RUNNING_MASK) + pi_data.cpu = entry & AVIC_PHYSICAL_ID_ENTRY_HOST_PHYSICAL_ID_MASK; + else + pi_data.cpu = -1; + ret = irq_set_vcpu_affinity(host_irq, &pi_data); if (ret) return ret; @@ -833,17 +846,6 @@ int avic_pi_update_irte(struct kvm_kernel_irqfd *irqfd, struct kvm *kvm, return -EIO; } - /* - * Update the target pCPU for IOMMU doorbells if the vCPU is - * running. If the vCPU is NOT running, i.e. is blocking or - * scheduled out, KVM will update the pCPU info when the vCPU - * is awakened and/or scheduled in. See also avic_vcpu_load(). - */ - entry = svm->avic_physical_id_entry; - if (entry & AVIC_PHYSICAL_ID_ENTRY_IS_RUNNING_MASK) - amd_iommu_update_ga(entry & AVIC_PHYSICAL_ID_ENTRY_HOST_PHYSICAL_ID_MASK, - pi_data.ir_data); - irqfd->irq_bypass_data = pi_data.ir_data; list_add(&irqfd->vcpu_list, &svm->ir_list); return 0; diff --git a/drivers/iommu/amd/iommu.c b/drivers/iommu/amd/iommu.c index 4fdf1502be69..b0b4c5ca16a8 100644 --- a/drivers/iommu/amd/iommu.c +++ b/drivers/iommu/amd/iommu.c @@ -3807,7 +3807,7 @@ int amd_iommu_update_ga(int cpu, void *data) } EXPORT_SYMBOL(amd_iommu_update_ga); -int amd_iommu_activate_guest_mode(void *data) +int amd_iommu_activate_guest_mode(void *data, int cpu) { struct amd_ir_data *ir_data = (struct amd_ir_data *)data; struct irte_ga *entry = (struct irte_ga *) ir_data->entry; @@ -3828,6 +3828,8 @@ int amd_iommu_activate_guest_mode(void *data) entry->hi.fields.vector = ir_data->ga_vector; entry->lo.fields_vapic.ga_tag = ir_data->ga_tag; + __amd_iommu_update_ga(entry, cpu); + return modify_irte_ga(ir_data->iommu, ir_data->irq_2_irte.devid, ir_data->irq_2_irte.index, entry); } @@ -3894,7 +3896,7 @@ static int amd_ir_set_vcpu_affinity(struct irq_data *data, void *info) ir_data->ga_root_ptr = (pi_data->vapic_addr >> 12); ir_data->ga_vector = pi_data->vector; ir_data->ga_tag = pi_data->ga_tag; - ret = amd_iommu_activate_guest_mode(ir_data); + ret = amd_iommu_activate_guest_mode(ir_data, pi_data->cpu); } else { ret = amd_iommu_deactivate_guest_mode(ir_data); } diff --git a/include/linux/amd-iommu.h b/include/linux/amd-iommu.h index fe0e16ffe0e5..c9f2df0c4596 100644 --- a/include/linux/amd-iommu.h +++ b/include/linux/amd-iommu.h @@ -32,7 +32,7 @@ extern int amd_iommu_register_ga_log_notifier(int (*notifier)(u32)); extern int amd_iommu_update_ga(int cpu, void *data); -extern int amd_iommu_activate_guest_mode(void *data); +extern int amd_iommu_activate_guest_mode(void *data, int cpu); extern int amd_iommu_deactivate_guest_mode(void *data); #else /* defined(CONFIG_AMD_IOMMU) && defined(CONFIG_IRQ_REMAP) */ @@ -48,7 +48,7 @@ static inline int amd_iommu_update_ga(int cpu, void *data) return 0; } -static inline int amd_iommu_activate_guest_mode(void *data) +static inline int amd_iommu_activate_guest_mode(void *data, int cpu) { return 0; }