From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pf1-f176.google.com (mail-pf1-f176.google.com [209.85.210.176]) (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 148F03AEB40 for ; Thu, 16 Jul 2026 20:54:42 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.210.176 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784235284; cv=none; b=bDz0dJHUc1QKuEQctP0h1/D/pvGfhV2b30u5xxDBXZJV7M1RLzTwuU/XfzbS6NIp9bCesm7dnKwrXPd0E+HDQ09BZ97A9J2QVVtoYY/c0wQxUiAK2OaJsJwumUB7IUTMCOMr3R019fWaNjiG5/1ST7nGb0m5wgNOGfulya+nZ/g= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784235284; c=relaxed/simple; bh=QlDleFf1thsudBLvDEeQpD3uIYK5RhVqCf8AZj/Gqzs=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=i8+52bRYQ3Zz/iAWO1iCADFQS5GkZfxCZ/BK4VbHHEvoZUCmwZLgO87RRGt+0UKkwRQIz0u/Dwfp4WVjWsf5ZzCnw6UqqAhXRLx4sntP2tN2q7vTSrXO2MPVSMZuxUDHldC+0Ni2z9JGoDn4SLJPjmtl3060tjDCqA1nB16Yovc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linaro.org; spf=pass smtp.mailfrom=linaro.org; dkim=pass (2048-bit key) header.d=linaro.org header.i=@linaro.org header.b=GqSjwfzK; arc=none smtp.client-ip=209.85.210.176 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linaro.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linaro.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=linaro.org header.i=@linaro.org header.b="GqSjwfzK" Received: by mail-pf1-f176.google.com with SMTP id d2e1a72fcca58-84536ecfc5bso3872048b3a.2 for ; Thu, 16 Jul 2026 13:54:42 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; t=1784235282; x=1784840082; darn=vger.kernel.org; h=in-reply-to:content-disposition:content-type:mime-version :references:message-id:subject:cc:to:from:date:from:to:cc:subject :date:message-id:reply-to:content-type; bh=HhLYnr/qR2b4y0zZ+sDHUxX9VDtn3ie68FSiMVa5FBY=; b=GqSjwfzKzSOmSjZLQUv9jQmXaXRaBc1PFmPURZy0mmEjdOtPOmWEbsnaI3kQIAfiMF TPR76XkYqG+6ZqJuAi8WYLfWaxdYlTfzxNv480pA4x38DIdbuJ+sspWTkRnKk/Nyv9Zd AulJqxi85cAnScLhK4aVIWqHAL2Kk7bH9thj4eqbxfm3bUYqSYrT9G7rKDJ9wZmxc2s3 fRLiqHiD9VE2E/DNWak3R5gPMQhHQoLeGgUu7keiLp/ZJLRwaBY6kYmwJTlZ7UUYhW9v v2Il3SUyRBPzLKGy+827RmlFrJXLvN7YL3rPo8/6a7tizSiCl9w4zv+Pw54JPTJTmyTQ RFwA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1784235282; x=1784840082; h=in-reply-to:content-disposition:content-type:mime-version :references:message-id:subject:cc:to:from:date:x-gm-gg :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to :content-type; bh=HhLYnr/qR2b4y0zZ+sDHUxX9VDtn3ie68FSiMVa5FBY=; b=T2VvQjPMq0jOPVbVhg8A9brWyc4NFzVnwxRWnh1U4aPL1zaQJ+keZqjDyAGJs59uTg g21ZX+0fS81pmmaSGhkEpOfwIIAvm1k3eGPLQOww7sJDBVVEEYR3GV/GZjfMFcEaBKvh 5XJ7x5gHmFOXgQ/egg54jZObanXANjnaRzPhRCVDAGsvDScDu+OSgqQTPE+97blBngRn gowHCCRioClkz29JhJYSrd5yCT+z4RtkuCXmGK8KOq8ugKMQrA3kxMphqEx35JT78Gl9 wM0xifPPZtvhNboL+Gasw4TPrNE/HdFWlgc2vVVXHR3D3ZG+vRhiIOb69/IrTEZotHXA l62w== X-Forwarded-Encrypted: i=1; AHgh+RoYBLuuc8eLNg5QldpnOeMQpEYwTGwM3xc6KCDFQPuzwyKRnA8ZGGDc2kca9IDByB8GT3w=@vger.kernel.org X-Gm-Message-State: AOJu0YyPxaSyfKM17oEYBiqPv+ki+YFXN0rmb4/2n7LWMPlRrN3xmtu3 T35G+WS8IY8atj/vQyt8E3AeIYhGH0kf/1+RWI+n23AnUl/fSDOkyeET3y4P8Lm8TZ4= X-Gm-Gg: AfdE7cmQJrkx1BUUGf0c8/ES6kbIScNhwlE9eXmKwprjFJdp1XP+DeB+7BcNThrp7GA 8sbAqTxVVh2j38zD3hf9TAGg0L6h+Vc1TgD3GzYYhol54AtMurOqIGj+hZxQZ1M70oBj36yFtkF NWr1PrLcv98+7XaT4tYKr6/wnw3VgdWncrK2oVOvAndq9FMXBgsoimdHn6WPDulhYB3ZD1NOCvM srOIV/2EGeK5w4ahmBIPPPsdiMdGMc5qvePS4K1Z1BCeWqyNxKlN05NNmBswnrzC6s9c5wKzO0M Fpla4/0VqMCHVKTT2icpoH4djv8v4QiV6W4ajS9QrsAoCL7XrYOn3fTTBieTVibljidDHg8xPN+ SG05XpaUUK+jVIMi3UtqZdKCtjH5ODEdfxI4gyPlcnZxcR+a4Ux2cW2VkvmhxN1+sNgdcWVhHqE 3XSGQQVQ== X-Received: by 2002:a05:6a00:3a01:b0:848:75a1:a0fa with SMTP id d2e1a72fcca58-84a6738bde1mr8608393b3a.67.1784235282318; Thu, 16 Jul 2026 13:54:42 -0700 (PDT) Received: from p14s ([2604:3d09:148c:c800:bc13:5578:20b0:9bee]) by smtp.gmail.com with ESMTPSA id d2e1a72fcca58-84a4f7dc8e7sm5302307b3a.47.2026.07.16.13.54.40 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 16 Jul 2026 13:54:41 -0700 (PDT) Date: Thu, 16 Jul 2026 14:54:39 -0600 From: Mathieu Poirier To: Gavin Shan Cc: berrange@redhat.com, kchamart@redhat.com, pierrick.bouvier@oss.qualcomm.com, peter.maydell@linaro.org, mst@redhat.com, cohuck@redhat.com, pbonzini@redhat.com, eblake@redhat.com, armbru@redhat.com, jpb@kernel.org, lorenzo.pieralisi@linaro.org, qemu-devel@nongnu.org, qemu-arm@nongnu.org, kvm@vger.kernel.org Subject: Re: [RFC v1 07/25] target/arm/kvm: Create scratch Realm VM when requested Message-ID: References: <20260707224306.1202330-1-mathieu.poirier@linaro.org> <20260707224306.1202330-8-mathieu.poirier@linaro.org> Precedence: bulk X-Mailing-List: kvm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: On Mon, Jul 13, 2026 at 03:30:31PM +1000, Gavin Shan wrote: > On 7/8/26 8:42 AM, Mathieu Poirier wrote: > > From: Jean-Philippe Brucker > > > > When a Realm is requested, create a scratch Realm VM by setting bit 8 > > of the argument given to the KVM_CREATE_VM ioctl(). Bit 7-0 are reserved > > for the guest PA size. > > > > Signed-off-by: Jean-Philippe Brucker > > Signed-off-by: Mathieu Poirier > > --- > > target/arm/kvm-rme.c | 8 ++++++++ > > target/arm/kvm-stub.c | 5 +++++ > > target/arm/kvm.c | 4 +++- > > target/arm/kvm_arm.h | 8 ++++++++ > > 4 files changed, 24 insertions(+), 1 deletion(-) > > > > diff --git a/target/arm/kvm-rme.c b/target/arm/kvm-rme.c > > index 90c1d30ba24c..f763d5ed6199 100644 > > --- a/target/arm/kvm-rme.c > > +++ b/target/arm/kvm-rme.c > > @@ -99,3 +99,11 @@ void kvm_arm_rme_vcpu_init(ARMCPU *cpu) > > cpu->kvm_rme = true; > > } > > + > > +int kvm_arm_rme_vm_type(void) > > +{ > > + if (rme_guest) { > > + return KVM_VM_TYPE_ARM_REALM; > > + } > > + return 0; > > +} > > We had official name for 0, which is KVM_VM_TYPE_ARM_NORMAL. Another question if > it's worthwhile to have this helper since it's equivalent to something as below, > which can be directly applied to the caller. > > > int vm_type = (current_machine && current_machine->cgs) ? KVM_VM_TYPE_ARM_REALM : > KVM_VM_TYPE_ARM_NORMAL; > Addressed. > > > diff --git a/target/arm/kvm-stub.c b/target/arm/kvm-stub.c > > index 4ab6f08637d1..6d52f172c5df 100644 > > --- a/target/arm/kvm-stub.c > > +++ b/target/arm/kvm-stub.c > > @@ -129,3 +129,8 @@ void kvm_arm_rme_vcpu_init(ARMCPU *cpu) > > { > > g_assert_not_reached(); > > } > > + > > +int kvm_arm_rme_vm_type(void) > > +{ > > + g_assert_not_reached(); > > +} > > diff --git a/target/arm/kvm.c b/target/arm/kvm.c > > index 4c212ed0c337..6aa1cd04e484 100644 > > --- a/target/arm/kvm.c > > +++ b/target/arm/kvm.c > > @@ -108,6 +108,7 @@ bool kvm_arm_create_scratch_host_vcpu(int *fdarray, > > { > > int ret = 0, kvmfd = -1, vmfd = -1, cpufd = -1; > > int max_vm_pa_size; > > + int vm_type; > > kvmfd = qemu_open_old("/dev/kvm", O_RDWR); > > if (kvmfd < 0) { > > @@ -117,8 +118,9 @@ bool kvm_arm_create_scratch_host_vcpu(int *fdarray, > > if (max_vm_pa_size < 0) { > > max_vm_pa_size = 0; > > } > > + vm_type = kvm_arm_rme_vm_type(); > > do { > > - vmfd = ioctl(kvmfd, KVM_CREATE_VM, max_vm_pa_size); > > + vmfd = ioctl(kvmfd, KVM_CREATE_VM, max_vm_pa_size | vm_type); > > } while (vmfd == -1 && errno == EINTR); > > if (vmfd < 0) { > > goto err; > > diff --git a/target/arm/kvm_arm.h b/target/arm/kvm_arm.h > > index 12ed1eee18b4..65ec1b970606 100644 > > --- a/target/arm/kvm_arm.h > > +++ b/target/arm/kvm_arm.h > > @@ -259,4 +259,12 @@ int kvm_arm_rme_init(MachineState *ms, KVMState *s); > > */ > > void kvm_arm_rme_vcpu_init(ARMCPU *cpu); > > +/** > > + * kvm_arm_rme_vm_type > > + * @ms: the machine state > > + * > > + * Returns the Realm KVM VM type if the user requested a Realm, 0 otherwise. > > + */ > > +int kvm_arm_rme_vm_type(void); > > + > > #endif > > Thanks, > Gavin >