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 71A74CA5FE3 for ; Sat, 3 Oct 2026 07:07:58 +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:References:Cc:To:From: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=l3nfWI+ujIzwCP1N5ZqG6Gm8qME+gKFGAFiRfhLvgDk=; b=VA4s3GmrC3byiRua2iJuV6849y W/9h/j9ICJPBXLW3n3MdPaEM7OQStCV2xNBErGzC+bryjSGzjq6YoA0qXeMpgJ+wI9C9auIfMUubR XGw18o0W0EXTA8mdmfNeZ7Cnv1SjbpFjm1bCvz4tLNablqzRO7MoeFrFQ4vigdEEbSeqdsNCAmvlh bulsJpaRsI9uGa5F5SqCN+sJHqE+wol5LSZNf0RjUxuLpXwC1+XTmHI7FL9hRGdVfu302U633Kw+0 OixLUgDIcWpBeIj+EyLNFel8GJlunyUw08CM3gvSm9bAO+kjC+aCawlB3pMnCR9qqCU/T9cCkXJjt 15boFycw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1xCtqZ-0000000D6iq-3yCN; Sat, 03 Oct 2026 07:07:51 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1xCtqW-0000000D6iV-3lRK for linux-arm-kernel@lists.infradead.org; Sat, 03 Oct 2026 07:07:50 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 25B942F; Sat, 3 Oct 2026 00:07:43 -0700 (PDT) Received: from [10.57.8.170] (unknown [10.57.8.170]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 163E63F85F; Sat, 3 Oct 2026 00:07:42 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=arm.com; s=foss; t=1791011266; bh=fcWSRwYqC7iDa1xgy0kg2U7wsZFZJLJk1a4HcvjWK5I=; h=Date:Subject:From:To:Cc:References:In-Reply-To:From; b=PPj0gM2RRh21a27DM/q2/tyeKO0DsJnY3GH0PWCJS7UVYAEtbBp7Ez9b8ZaULD6Xj 2dnwFTOkOPfgCECZeEJndniLsNWLRZQ+EHqxBlRJDHEgJ740NaFO9F3W9cUZE9u/PJ y52tz3Ck56R1gHYTC5TcmWjSuYfZE7m4ksWwojiM= Message-ID: Date: Sat, 3 Oct 2026 08:07:39 +0100 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v21 05/23] KVM: arm64: Track the type of VM in kvm_arch Content-Language: en-GB From: Suzuki K Poulose To: Marc Zyngier , Fuad Tabba Cc: kvm@vger.kernel.org, kvmarm@lists.linux.dev, 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, gshan@redhat.com, joey.gouly@arm.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, sudeep.holla@arm.com, jonathan.cameron@oss.qualcomm.com References: <20261001210703.1597150-1-suzuki.poulose@arm.com> <20261001210703.1597150-6-suzuki.poulose@arm.com> <86se2o2rbs.wl-maz@kernel.org> <86pkxs2npx.wl-maz@kernel.org> <86o6dc2ka1.wl-maz@kernel.org> <83e79119-b331-4640-b2c7-cc8135d71c77@arm.com> In-Reply-To: <83e79119-b331-4640-b2c7-cc8135d71c77@arm.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.9.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20261003_000749_017718_E75B8CD3 X-CRM114-Status: GOOD ( 18.14 ) 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 On 03/10/2026 06:53, Suzuki K Poulose wrote: > On 02/10/2026 16:29, Marc Zyngier wrote: >> On Fri, 02 Oct 2026 15:37:00 +0100, >> Fuad Tabba wrote: >>> >>> Hi Marc, >>> >>> On Fri, 02 Oct 2026 15:15:06 +0100, Marc Zyngier wrote: >>> [...] >>>> Honestly, we introduce the flavor stuff to make it easy to match >>>> things on a particular VM type in a readable way. So why isn't this >>>> reading: >>>> >>>>          if (vcpu->kvm->arch.vm_flavor != VM_PROTECTED_PKVM) >>>>                  return; >>> >>> I know this is a sketch, but just in case: that's inverted. The sync >>> only applies to non-protected pKVM VMs (EL2 ignores it for protected >>> ones), so it would be != VM_PKVM. >> >> See what I meant about this stuff being completely intractable? I >> still have no idea what it means! ;-) >> > > Just to be clear: unprotected_pkvm() != (vm_flavor != VM_PROTECED_PKVM). > Rather, unprotected_pkvm => (vm_flavor == VM_PKVM). > > And the code wanted to bail out early for !unprotected_pkvm(). We can > stick in "is_protected_kvm_enabled()" for unprotected_pkvm predicate > > But, I can drop the helper and use the vm_flavor check. FWIW: Here is the diff for the above change. If you are happy with the following, I could fold this in. diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c index 90547fbbc8ad7..bcec14c587119 100644 --- a/arch/arm64/kvm/arm.c +++ b/arch/arm64/kvm/arm.c @@ -772,7 +772,7 @@ void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu) kvm_call_hyp_nvhe(__pkvm_vcpu_put); /* __pkvm_vcpu_put implies a sync of the state */ - if (kvm_vm_is_unprotected_pkvm(vcpu->kvm)) + if (vcpu->kvm->arch.vm_flavor == VM_PKVM) vcpu_set_flag(vcpu, PKVM_HOST_STATE_DIRTY); } @@ -1006,7 +1006,7 @@ int kvm_arch_vcpu_run_pid_change(struct kvm_vcpu *vcpu) if (is_protected_kvm_enabled()) { /* Start with the vcpu in a dirty state */ - if (kvm_vm_is_unprotected_pkvm(vcpu->kvm)) + if (vcpu->kvm->arch.vm_flavor == VM_PKVM) vcpu_set_flag(vcpu, PKVM_HOST_STATE_DIRTY); ret = pkvm_create_hyp_vm(kvm); if (ret) diff --git a/arch/arm64/kvm/handle_exit.c b/arch/arm64/kvm/handle_exit.c index 384c5d258c7f8..4e16e7d165515 100644 --- a/arch/arm64/kvm/handle_exit.c +++ b/arch/arm64/kvm/handle_exit.c @@ -490,7 +490,7 @@ static void handle_exit_pkvm_state(struct kvm_vcpu *vcpu, int exception_index) { int exception_code = ARM_EXCEPTION_CODE(exception_index); - if (!kvm_vm_is_unprotected_pkvm(vcpu->kvm)) + if (!is_protected_kvm_enabled() || vcpu->kvm->arch.vm_flavor != VM_PKVM) return; /* Cheers Suzuki> > Cheers > Suzuki > >>     M. >> >