From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 8A7DDC79FB7 for ; Thu, 10 Sep 2026 04:00:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: Content-Type:In-Reply-To:From:References:Cc:To:Subject:MIME-Version:Date: Message-ID:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=4MZLtSduN3n4DstPQZClxNsj5BwxMrrkDzTkcMmPEOA=; b=iBM+ahc0nFUzcrA3YJdriB7RKR HB5KBlRuAO31UL9bM8tePfphqyWH9OG+JSFnSEV3TAcnhy/BFf3ID/YgKXMZjvmv/S0y/ZoQgoVAV eMuFIZIpw5lMdohvhcC1ZcJK7pHUPk28k74EPiRJD5vZmOCuI/uuxn8yLS2ORGtPhFB3aqsPkUiUC kmIxWnCaF1D7QH721Sif49xEAQQs/9BGhQQfNnC86uhN2RvlHt6cUJdj+zscBcALHplT4JkFok84B Pf+8KNap7C1A9fk44wRvMAt+Dl+noccTc0yooHOrnPQK7VyryzHTJoPCSFeAdoQtP26xGPu7Gj4H4 wg5JNtcQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1x4Vxa-0000000DKoG-2Xy5; Thu, 10 Sep 2026 04:00:26 +0000 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]) by bombadil.infradead.org with esmtps (Exim 4.99.1 #2 (Red Hat Linux)) id 1x4VxY-0000000DKnt-0N54 for linux-arm-kernel@lists.infradead.org; Thu, 10 Sep 2026 04:00:25 +0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1789012822; 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: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=4MZLtSduN3n4DstPQZClxNsj5BwxMrrkDzTkcMmPEOA=; b=HHeQhTIkmuESr+NZ+XPjh4G34hLdj1MTWpnRxq32YTmByWxGJWnwC7pcMXspxadyExJIj9 s+VX0lwKbg2DIBZQp6GztmQ9+NRu/nAuMGi2RZwYWqyO/LmqChsIo2YOEfDhcq5FHZ8V4r 5zN2I4m98SRAD9ClaZm6xgzsP59zakM= Received: from mail-pl1-f199.google.com (mail-pl1-f199.google.com [209.85.214.199]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-59-WO1pldVBMXu1MiljuBhLOw-1; Thu, 10 Sep 2026 00:00:20 -0400 X-MC-Unique: WO1pldVBMXu1MiljuBhLOw-1 X-Mimecast-MFC-AGG-ID: WO1pldVBMXu1MiljuBhLOw_1789012819 Received: by mail-pl1-f199.google.com with SMTP id d9443c01a7336-2d55d8cd938so114470595ad.1 for ; Wed, 09 Sep 2026 21:00:20 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1789012819; x=1789617619; h=content-transfer-encoding:content-type:in-reply-to:from :content-language:references:cc:to:subject:user-agent:mime-version :date:message-id:x-gm-gg:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to:content-type; bh=4MZLtSduN3n4DstPQZClxNsj5BwxMrrkDzTkcMmPEOA=; b=fMYD4D1l4rLFFjJahWFV6o13sJryLCSiCN8mfkVqhr6ldw4tnzS6im8ufDG37sGqZk Kj3eh+CHzqcIjwu5gS3l192N2QgPtHsbP6PVrecpE4xDYVvYi5+XjeJY7toUOwGDPhp4 7EJ6ZRbsElbB/Hd1CvZkgRiFd2dn4EZ/8Uisy0p02wClphXudzTizR7d94HbGSqontXx 0TSaYhSOwGkG8p+4FcfUKDi/FVZC9tzQQ3nALKDHog6QqMsQo3f4M7J3yFJlzmBVOw+f BdU1yYPQzKyueLcyeUjNu3QRXloffQvyXv7oXOctEuqBNuV4C2NCBO687MARUeuVLNRS uKvA== X-Forwarded-Encrypted: i=1; AKwUvBxi2RSgoQV5pn8D2Hhk+q0Zyee+fuBtm0eTjXNQubm2ZkbkCT04NTPsiKsdNfyGuU/uZ7HA3RskRpuRuFxuP1Qr@lists.infradead.org X-Gm-Message-State: AFuF++kDWxFkUNefY5KSuAy5vJPUbU7AYDwwh/Kcg9uYPB6vgtoTUyyy hSGU3LH9NN35Yi7UhBq0MHozRpcQXnKIxwokI5azn+Qrt2n5k+GJlwXu92N6oCc+r+rWCsCS1qB mtol+NSeKCWRENl7LtqpcEAgByjM09f1u6UTYcGoToVPmUqn8mgVBv+Ovv6rz/FMLWmIwo0Syuw lv X-Gm-Gg: AYBFou0tuF+09Cgn/6+a/biTIn8pG9HE1MQRr+GNrcwelbvA6PNsIJ3VVQTnRLXzhmA NtmXGVdWtKsiTCXHC7QPOj0dsK5iwu8uD8GtaSoo9hYqSqfNdJ5x7WtBei1EYmvEoeZT1XKoLxa UTQ/V6Qobp7cvDVi6go9Kg+LvARGcXCPVHImwNtBQ0edXVpjHb26FuiJqICcPYzWCZ0dDXKwqhx VDVeTgN0pnlREgr0rjFr4eAk3f/XZjw745H5wka+V+elY8LujXzmaQXriG4op6zj+gjzVW/40VZ aLFjpa11L6XOyoQKnNbQzILov+v1DQ48BaIBmXCTf+IAVbcVKZFVbe1C0nIUDb09OcozhKjfc3/ rryPiD2XlQdCeBQouc3l1VkQcEq0T1Mxj7LmC1Ri4MA== X-Received: by 2002:a17:902:ef44:b0:2cc:6018:f030 with SMTP id d9443c01a7336-2db1259d1f8mr542225235ad.14.1789012819322; Wed, 09 Sep 2026 21:00:19 -0700 (PDT) X-Received: by 2002:a17:902:ef44:b0:2cc:6018:f030 with SMTP id d9443c01a7336-2db1259d1f8mr542224465ad.14.1789012818867; Wed, 09 Sep 2026 21:00:18 -0700 (PDT) Received: from [192.168.68.52] (n175-34-8-244.mrk21.qld.optusnet.com.au. [175.34.8.244]) by smtp.gmail.com with ESMTPSA id d9443c01a7336-2db149ccf2esm82468805ad.73.2026.09.09.21.00.09 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 09 Sep 2026 21:00:18 -0700 (PDT) Message-ID: Date: Thu, 10 Sep 2026 14:00:06 +1000 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v17 04/20] KVM: arm64: Refactor the vcpu_load to allow for VM specific callbacks To: Suzuki K Poulose , kvm@vger.kernel.org, kvmarm@lists.linux.dev Cc: maz@kernel.org, will@kernel.org, catalin.marinas@arm.com, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, steven.price@arm.com, aneesh.kumar@kernel.org, oupton@kernel.org, joey.gouly@arm.com, tabba@google.com, yuzenghui@huawei.com, linux-coco@lists.linux.dev, gankulkarni@os.amperecomputing.com, sdonthineni@nvidia.com, alpergun@google.com, fj0570is@fujitsu.com, WeiLin.Chang@arm.com, lpieralisi@kernel.org, enju.kohei@fujitsu.com References: <20260908162223.1683432-1-suzuki.poulose@arm.com> <20260908162223.1683432-5-suzuki.poulose@arm.com> From: Gavin Shan In-Reply-To: <20260908162223.1683432-5-suzuki.poulose@arm.com> X-Mimecast-Spam-Score: 0 X-Mimecast-MFC-PROC-ID: 5Jc-8rimTugQOQYiNIoy81XxaMj-iyW3Ybk1zyWh5-0_1789012819 X-Mimecast-Originator: redhat.com Content-Language: en-US Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.9.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260909_210024_226250_495399F5 X-CRM114-Status: GOOD ( 21.65 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Hi Suzuki, On 9/9/26 2:22 AM, Suzuki K Poulose wrote: > Based on a work by Marc Zyngier > > To keep the VCPU load/put handling cleaner with the different kinds of VM types, > we are about to introduce VM specific callbacks to do just the right thing. > In preparation for that, make some refactoring to add the change easier. > > No functional changes intended. > > Signed-off-by: Suzuki K Poulose > --- > arch/arm64/kvm/arm.c | 46 +++++++++++++++++++++++++++----------------- > 1 file changed, 28 insertions(+), 18 deletions(-) > Nitpicks below, none of them are introduced by this patch itself. In either way: Reviewed-by: Gavin Shan > diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c > index 67f1ff9bc4fbe..51fc651267157 100644 > --- a/arch/arm64/kvm/arm.c > +++ b/arch/arm64/kvm/arm.c > @@ -683,14 +683,11 @@ static bool kvm_vcpu_should_clear_twe(struct kvm_vcpu *vcpu) > return single_task_running(); > } > > -void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu) > +static void vcpu_prepare_mmu(struct kvm_vcpu *vcpu) > { > struct kvm_s2_mmu *mmu; > int *last_ran; > > - if (is_protected_kvm_enabled()) > - goto nommu; > - > if (vcpu_has_nv(vcpu)) > kvm_vcpu_load_hw_mmu(vcpu); > > @@ -720,10 +717,33 @@ void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu) > kvm_call_hyp(__kvm_flush_cpu_context, mmu); > *last_ran = vcpu->vcpu_idx; > } > +} > + > +static void vcpu_set_wfx_traps(struct kvm_vcpu *vcpu) > +{ > + if (kvm_vcpu_should_clear_twe(vcpu)) > + vcpu->arch.hcr_el2 &= ~HCR_TWE; > + else > + vcpu->arch.hcr_el2 |= HCR_TWE; > + > + if (kvm_vcpu_should_clear_twi(vcpu)) > + vcpu->arch.hcr_el2 &= ~HCR_TWI; > + else > + vcpu->arch.hcr_el2 |= HCR_TWI; > +} > + It seems FIELD_MODIFY() can be applied here if no visible constraints exist: FIELD_MODIFY(HCR_TWE, vcpu->arch.hcr_el2, !kvm_vcpu_should_clear_twe(vcpu)); FIELD_MODIFY(HCR_TWI, vcpu->arch.hcr_el2, !kvm_vcpu_should_clear_twi(vcpu)); > +static void vcpu_load_pvtime(struct kvm_vcpu *vcpu) > +{ > + if (kvm_arm_is_pvtime_enabled(&vcpu->arch)) > + kvm_make_request(KVM_REQ_RECORD_STEAL, vcpu); > +} > + > +void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu) > +{ > + if (!is_protected_kvm_enabled()) > + vcpu_prepare_mmu(vcpu); > I think we probably try to depend on kvm->arch.vm_flavor instead of !is_protected_kvm_enabled(). struct kvm *kvm = vcpu->kvm; if (kvm_vm_is_protected(kvm) || kvm_vm_flavor_eq(kvm, VM_PKVM)) vcpu_prepare_mmu(vcpu); > -nommu: > vcpu->cpu = cpu; > - > /* > * The timer must be loaded before the vgic to correctly set up physical > * interrupt deactivation in nested state (e.g. timer interrupt). > @@ -736,19 +756,9 @@ void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu) > kvm_vcpu_load_vhe(vcpu); > kvm_arch_vcpu_load_fp(vcpu); > kvm_vcpu_pmu_restore_guest(vcpu); > - if (kvm_arm_is_pvtime_enabled(&vcpu->arch)) > - kvm_make_request(KVM_REQ_RECORD_STEAL, vcpu); > - > - if (kvm_vcpu_should_clear_twe(vcpu)) > - vcpu->arch.hcr_el2 &= ~HCR_TWE; > - else > - vcpu->arch.hcr_el2 |= HCR_TWE; > - > - if (kvm_vcpu_should_clear_twi(vcpu)) > - vcpu->arch.hcr_el2 &= ~HCR_TWI; > - else > - vcpu->arch.hcr_el2 |= HCR_TWI; > > + vcpu_load_pvtime(vcpu); > + vcpu_set_wfx_traps(vcpu); > vcpu_set_pauth_traps(vcpu); > > if (is_protected_kvm_enabled()) { Thanks, Gavin