From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 4FCEA316199; Sat, 3 Oct 2026 05:53:43 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.140.110.172 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1791006825; cv=none; b=Bj0t6ygmfFmPyCh1gDjQtGtswDEMPGOYxATnhxASuUr5l3FlfwN6IRVG+W51o0ae3YuuHvKwf2KLPNuswNyXh4abYNhsbkXo3Rhrh9EHxsppES/YfwbQ3a121wvDh+ULH8x/jF78g+bx82qIoUu5uHp5++mm/b+EXbQGPgAU+2I= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1791006825; c=relaxed/simple; bh=Y/5WUAxYLssgu4Iz+g+/3NBSAG3D07mwZyV0pgPP1qU=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=E3KqVkaGeE+z685L8F/kK1qlzD4Cmfj9JR9jzaOayut5yNbrjuXZlvdUHpvWwjGJIGmcUD7I9dKG6iydIvXGkt3fHDn4e29YWY8JytPJVCy7BS0gezU12mo0SWN2IuD+Ce+BCOZ143zA/z0PXmhf3pBBsuB1wuNIOuy3yU6gsFw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com; spf=pass smtp.mailfrom=arm.com; dkim=pass (1024-bit key) header.d=arm.com header.i=@arm.com header.b=l2zLONPo; arc=none smtp.client-ip=217.140.110.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arm.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=arm.com header.i=@arm.com header.b="l2zLONPo" 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 F2A862F; Fri, 2 Oct 2026 22:53:38 -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 E6D383F85F; Fri, 2 Oct 2026 22:53:38 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=arm.com; s=foss; t=1791006822; bh=Y/5WUAxYLssgu4Iz+g+/3NBSAG3D07mwZyV0pgPP1qU=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=l2zLONPof6gNkcOzAA4NcwT1p7hp3q0YKZisEyAbUksNskY75KsVsFtdpWNBcPDwQ AHC0wncAulPsibkhe2v1hdDo9fSjgHlahQlDCc5zmMcWZUjVZEXP1kf4J9FU/ILqUv sjI866VD2ar0oJ+Vqeolkz9ZrKqc3O76UrB2FEhE= Message-ID: <83e79119-b331-4640-b2c7-cc8135d71c77@arm.com> Date: Sat, 3 Oct 2026 06:53:35 +0100 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: 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 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> From: Suzuki K Poulose In-Reply-To: <86o6dc2ka1.wl-maz@kernel.org> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit 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. Cheers Suzuki > M. >