From mboxrd@z Thu Jan 1 00:00:00 1970 From: Alexandru Elisei Subject: Re: [kvmtool PATCH v9 5/5] KVM: arm/arm64: Add a vcpu feature for pointer authentication Date: Wed, 17 Apr 2019 09:55:25 +0100 Message-ID: <07e2284a-aac9-4200-c60d-7bb2bdc67bce@arm.com> References: <1555039236-10608-1-git-send-email-amit.kachhap@arm.com> <1555039236-10608-6-git-send-email-amit.kachhap@arm.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from localhost (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id 3156C4A4E4 for ; Wed, 17 Apr 2019 04:55:34 -0400 (EDT) Received: from mm01.cs.columbia.edu ([127.0.0.1]) by localhost (mm01.cs.columbia.edu [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 82JwLnV-wrj4 for ; Wed, 17 Apr 2019 04:55:32 -0400 (EDT) Received: from foss.arm.com (foss.arm.com [217.140.101.70]) by mm01.cs.columbia.edu (Postfix) with ESMTP id A52BA4A4AD for ; Wed, 17 Apr 2019 04:55:32 -0400 (EDT) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 1B414374 for ; Wed, 17 Apr 2019 01:55:32 -0700 (PDT) Received: from [10.1.215.53] (e121566-lin.cambridge.arm.com [10.1.215.53]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id B9B013F690 for ; Wed, 17 Apr 2019 01:55:31 -0700 (PDT) In-Reply-To: <1555039236-10608-6-git-send-email-amit.kachhap@arm.com> Content-Language: en-US List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: kvmarm-bounces@lists.cs.columbia.edu Sender: kvmarm-bounces@lists.cs.columbia.edu To: kvmarm@lists.cs.columbia.edu List-Id: kvmarm@lists.cs.columbia.edu Hello, On 4/12/19 4:20 AM, Amit Daniel Kachhap wrote: > This patch adds a runtime capabality for KVM tool to enable Arm64 8.3 > Pointer Authentication in guest kernel. Two vcpu features > KVM_ARM_VCPU_PTRAUTH_[ADDRESS/GENERIC] are supplied together to enable > Pointer Authentication in KVM guest after checking the capability. > > Command line options --enable-ptrauth and --disable-ptrauth are added > to use this feature. However, if those options are not provided then > also this feature is enabled if host supports this capability. > > The macros defined in the headers are not in sync and should be replaced > from the upstream. > > Signed-off-by: Amit Daniel Kachhap > --- > Changes since v8: > * Added option --enable-ptrauth and --disable-ptrauth to use ptrauth. Also > enable ptrauth if no option provided and Host supports ptrauth. [Dave Martin] > * The macro definition are not linear as the kvmtool is not synchronised with the > kernel changes present in kvmarm/next tree. > > arm/aarch32/include/kvm/kvm-cpu-arch.h | 1 + > arm/aarch64/include/asm/kvm.h | 2 ++ > arm/aarch64/include/kvm/kvm-config-arch.h | 6 +++++- > arm/aarch64/include/kvm/kvm-cpu-arch.h | 2 ++ > arm/include/arm-common/kvm-config-arch.h | 2 ++ > arm/kvm-cpu.c | 11 +++++++++++ > include/linux/kvm.h | 2 ++ > 7 files changed, 25 insertions(+), 1 deletion(-) > > diff --git a/arm/aarch32/include/kvm/kvm-cpu-arch.h b/arm/aarch32/include/kvm/kvm-cpu-arch.h > index d28ea67..520ea76 100644 > --- a/arm/aarch32/include/kvm/kvm-cpu-arch.h > +++ b/arm/aarch32/include/kvm/kvm-cpu-arch.h > @@ -13,4 +13,5 @@ > #define ARM_CPU_ID 0, 0, 0 > #define ARM_CPU_ID_MPIDR 5 > > +#define ARM_VCPU_PTRAUTH_FEATURE 0 > #endif /* KVM__KVM_CPU_ARCH_H */ > diff --git a/arm/aarch64/include/asm/kvm.h b/arm/aarch64/include/asm/kvm.h > index 97c3478..a2546e6 100644 > --- a/arm/aarch64/include/asm/kvm.h > +++ b/arm/aarch64/include/asm/kvm.h > @@ -102,6 +102,8 @@ struct kvm_regs { > #define KVM_ARM_VCPU_EL1_32BIT 1 /* CPU running a 32bit VM */ > #define KVM_ARM_VCPU_PSCI_0_2 2 /* CPU uses PSCI v0.2 */ > #define KVM_ARM_VCPU_PMU_V3 3 /* Support guest PMUv3 */ > +#define KVM_ARM_VCPU_PTRAUTH_ADDRESS 5 /* CPU uses address pointer authentication */ > +#define KVM_ARM_VCPU_PTRAUTH_GENERIC 6 /* CPU uses generic pointer authentication */ > > struct kvm_vcpu_init { > __u32 target; > diff --git a/arm/aarch64/include/kvm/kvm-config-arch.h b/arm/aarch64/include/kvm/kvm-config-arch.h > index 04be43d..0279b13 100644 > --- a/arm/aarch64/include/kvm/kvm-config-arch.h > +++ b/arm/aarch64/include/kvm/kvm-config-arch.h > @@ -8,7 +8,11 @@ > "Create PMUv3 device"), \ > OPT_U64('\0', "kaslr-seed", &(cfg)->kaslr_seed, \ > "Specify random seed for Kernel Address Space " \ > - "Layout Randomization (KASLR)"), > + "Layout Randomization (KASLR)"), \ > + OPT_BOOLEAN('\0', "enable-ptrauth", &(cfg)->enable_ptrauth, \ > + "Enables pointer authentication"), \ > + OPT_BOOLEAN('\0', "disable-ptrauth", &(cfg)->disable_ptrauth, \ > + "Disables pointer authentication"), > > #include "arm-common/kvm-config-arch.h" > > diff --git a/arm/aarch64/include/kvm/kvm-cpu-arch.h b/arm/aarch64/include/kvm/kvm-cpu-arch.h > index a9d8563..fcc2107 100644 > --- a/arm/aarch64/include/kvm/kvm-cpu-arch.h > +++ b/arm/aarch64/include/kvm/kvm-cpu-arch.h > @@ -17,4 +17,6 @@ > #define ARM_CPU_CTRL 3, 0, 1, 0 > #define ARM_CPU_CTRL_SCTLR_EL1 0 > > +#define ARM_VCPU_PTRAUTH_FEATURE ((1UL << KVM_ARM_VCPU_PTRAUTH_ADDRESS) \ > + | (1UL << KVM_ARM_VCPU_PTRAUTH_GENERIC)) > #endif /* KVM__KVM_CPU_ARCH_H */ > diff --git a/arm/include/arm-common/kvm-config-arch.h b/arm/include/arm-common/kvm-config-arch.h > index 5734c46..1b4287d 100644 > --- a/arm/include/arm-common/kvm-config-arch.h > +++ b/arm/include/arm-common/kvm-config-arch.h > @@ -10,6 +10,8 @@ struct kvm_config_arch { > bool aarch32_guest; > bool has_pmuv3; > u64 kaslr_seed; > + bool enable_ptrauth; > + bool disable_ptrauth; > enum irqchip_type irqchip; > u64 fw_addr; > }; > diff --git a/arm/kvm-cpu.c b/arm/kvm-cpu.c > index 7780251..a45a649 100644 > --- a/arm/kvm-cpu.c > +++ b/arm/kvm-cpu.c > @@ -69,6 +69,17 @@ struct kvm_cpu *kvm_cpu__arch_init(struct kvm *kvm, unsigned long cpu_id) > } > > /* > + * Always enable Pointer Authentication if requested. If system supports > + * this extension then also enable it by default provided no disable > + * request present. > + */ > + if ((kvm->cfg.arch.enable_ptrauth) || > + (kvm__supports_extension(kvm, KVM_CAP_ARM_PTRAUTH_ADDRESS) && > + kvm__supports_extension(kvm, KVM_CAP_ARM_PTRAUTH_GENERIC) && > + !kvm->cfg.arch.disable_ptrauth)) I take it that: (1) Having both --enable-ptrauth and --disable-ptrauth present on the kvmtools command line is allowed (2) --enable-ptrauth takes precedence over --disable-ptrauth. Have you considered returning an error if both are present? Having --enable-ptrauth take precedence over --disable-ptrauth looks arbitrary to me (my expectations would have been for --disable-ptrauth to have precendece) and probably the user is doing something wrong if kvmtools is invoked with both arguments. > + vcpu_init.features[0] |= ARM_VCPU_PTRAUTH_FEATURE; > + > + /* > * If the preferred target ioctl is successful then > * use preferred target else try each and every target type > */ > diff --git a/include/linux/kvm.h b/include/linux/kvm.h > index 6d4ea4b..de1033b 100644 > --- a/include/linux/kvm.h > +++ b/include/linux/kvm.h > @@ -988,6 +988,8 @@ struct kvm_ppc_resize_hpt { > #define KVM_CAP_ARM_VM_IPA_SIZE 165 > #define KVM_CAP_MANUAL_DIRTY_LOG_PROTECT 166 > #define KVM_CAP_HYPERV_CPUID 167 > +#define KVM_CAP_ARM_PTRAUTH_ADDRESS 169 > +#define KVM_CAP_ARM_PTRAUTH_GENERIC 170 > > #ifdef KVM_CAP_IRQ_ROUTING > 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 X-Spam-Level: X-Spam-Status: No, score=-7.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9975AC10F12 for ; Wed, 17 Apr 2019 08:55:37 +0000 (UTC) Received: from mm01.cs.columbia.edu (mm01.cs.columbia.edu [128.59.11.253]) by mail.kernel.org (Postfix) with ESMTP id 2D9992073F for ; Wed, 17 Apr 2019 08:55:37 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 2D9992073F Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kvmarm-bounces@lists.cs.columbia.edu Received: from localhost (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id A29B24A4F3; Wed, 17 Apr 2019 04:55:36 -0400 (EDT) X-Virus-Scanned: at lists.cs.columbia.edu Received: from mm01.cs.columbia.edu ([127.0.0.1]) by localhost (mm01.cs.columbia.edu [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 0QP58ZKXUbwU; Wed, 17 Apr 2019 04:55:35 -0400 (EDT) Received: from mm01.cs.columbia.edu (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id 4C1F84A49F; Wed, 17 Apr 2019 04:55:35 -0400 (EDT) Received: from localhost (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id 3156C4A4E4 for ; Wed, 17 Apr 2019 04:55:34 -0400 (EDT) X-Virus-Scanned: at lists.cs.columbia.edu Received: from mm01.cs.columbia.edu ([127.0.0.1]) by localhost (mm01.cs.columbia.edu [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 82JwLnV-wrj4 for ; Wed, 17 Apr 2019 04:55:32 -0400 (EDT) Received: from foss.arm.com (foss.arm.com [217.140.101.70]) by mm01.cs.columbia.edu (Postfix) with ESMTP id A52BA4A4AD for ; Wed, 17 Apr 2019 04:55:32 -0400 (EDT) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 1B414374 for ; Wed, 17 Apr 2019 01:55:32 -0700 (PDT) Received: from [10.1.215.53] (e121566-lin.cambridge.arm.com [10.1.215.53]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id B9B013F690 for ; Wed, 17 Apr 2019 01:55:31 -0700 (PDT) Subject: Re: [kvmtool PATCH v9 5/5] KVM: arm/arm64: Add a vcpu feature for pointer authentication To: kvmarm@lists.cs.columbia.edu References: <1555039236-10608-1-git-send-email-amit.kachhap@arm.com> <1555039236-10608-6-git-send-email-amit.kachhap@arm.com> From: Alexandru Elisei Message-ID: <07e2284a-aac9-4200-c60d-7bb2bdc67bce@arm.com> Date: Wed, 17 Apr 2019 09:55:25 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.6.1 MIME-Version: 1.0 In-Reply-To: <1555039236-10608-6-git-send-email-amit.kachhap@arm.com> Content-Language: en-US X-BeenThere: kvmarm@lists.cs.columbia.edu X-Mailman-Version: 2.1.14 Precedence: list List-Id: Where KVM/ARM decisions are made List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Errors-To: kvmarm-bounces@lists.cs.columbia.edu Sender: kvmarm-bounces@lists.cs.columbia.edu Message-ID: <20190417085525.lZbseYc_XwdcLuPZKieVNW8LsnyBmAMrCglyjFmgcb4@z> Hello, On 4/12/19 4:20 AM, Amit Daniel Kachhap wrote: > This patch adds a runtime capabality for KVM tool to enable Arm64 8.3 > Pointer Authentication in guest kernel. Two vcpu features > KVM_ARM_VCPU_PTRAUTH_[ADDRESS/GENERIC] are supplied together to enable > Pointer Authentication in KVM guest after checking the capability. > > Command line options --enable-ptrauth and --disable-ptrauth are added > to use this feature. However, if those options are not provided then > also this feature is enabled if host supports this capability. > > The macros defined in the headers are not in sync and should be replaced > from the upstream. > > Signed-off-by: Amit Daniel Kachhap > --- > Changes since v8: > * Added option --enable-ptrauth and --disable-ptrauth to use ptrauth. Also > enable ptrauth if no option provided and Host supports ptrauth. [Dave Martin] > * The macro definition are not linear as the kvmtool is not synchronised with the > kernel changes present in kvmarm/next tree. > > arm/aarch32/include/kvm/kvm-cpu-arch.h | 1 + > arm/aarch64/include/asm/kvm.h | 2 ++ > arm/aarch64/include/kvm/kvm-config-arch.h | 6 +++++- > arm/aarch64/include/kvm/kvm-cpu-arch.h | 2 ++ > arm/include/arm-common/kvm-config-arch.h | 2 ++ > arm/kvm-cpu.c | 11 +++++++++++ > include/linux/kvm.h | 2 ++ > 7 files changed, 25 insertions(+), 1 deletion(-) > > diff --git a/arm/aarch32/include/kvm/kvm-cpu-arch.h b/arm/aarch32/include/kvm/kvm-cpu-arch.h > index d28ea67..520ea76 100644 > --- a/arm/aarch32/include/kvm/kvm-cpu-arch.h > +++ b/arm/aarch32/include/kvm/kvm-cpu-arch.h > @@ -13,4 +13,5 @@ > #define ARM_CPU_ID 0, 0, 0 > #define ARM_CPU_ID_MPIDR 5 > > +#define ARM_VCPU_PTRAUTH_FEATURE 0 > #endif /* KVM__KVM_CPU_ARCH_H */ > diff --git a/arm/aarch64/include/asm/kvm.h b/arm/aarch64/include/asm/kvm.h > index 97c3478..a2546e6 100644 > --- a/arm/aarch64/include/asm/kvm.h > +++ b/arm/aarch64/include/asm/kvm.h > @@ -102,6 +102,8 @@ struct kvm_regs { > #define KVM_ARM_VCPU_EL1_32BIT 1 /* CPU running a 32bit VM */ > #define KVM_ARM_VCPU_PSCI_0_2 2 /* CPU uses PSCI v0.2 */ > #define KVM_ARM_VCPU_PMU_V3 3 /* Support guest PMUv3 */ > +#define KVM_ARM_VCPU_PTRAUTH_ADDRESS 5 /* CPU uses address pointer authentication */ > +#define KVM_ARM_VCPU_PTRAUTH_GENERIC 6 /* CPU uses generic pointer authentication */ > > struct kvm_vcpu_init { > __u32 target; > diff --git a/arm/aarch64/include/kvm/kvm-config-arch.h b/arm/aarch64/include/kvm/kvm-config-arch.h > index 04be43d..0279b13 100644 > --- a/arm/aarch64/include/kvm/kvm-config-arch.h > +++ b/arm/aarch64/include/kvm/kvm-config-arch.h > @@ -8,7 +8,11 @@ > "Create PMUv3 device"), \ > OPT_U64('\0', "kaslr-seed", &(cfg)->kaslr_seed, \ > "Specify random seed for Kernel Address Space " \ > - "Layout Randomization (KASLR)"), > + "Layout Randomization (KASLR)"), \ > + OPT_BOOLEAN('\0', "enable-ptrauth", &(cfg)->enable_ptrauth, \ > + "Enables pointer authentication"), \ > + OPT_BOOLEAN('\0', "disable-ptrauth", &(cfg)->disable_ptrauth, \ > + "Disables pointer authentication"), > > #include "arm-common/kvm-config-arch.h" > > diff --git a/arm/aarch64/include/kvm/kvm-cpu-arch.h b/arm/aarch64/include/kvm/kvm-cpu-arch.h > index a9d8563..fcc2107 100644 > --- a/arm/aarch64/include/kvm/kvm-cpu-arch.h > +++ b/arm/aarch64/include/kvm/kvm-cpu-arch.h > @@ -17,4 +17,6 @@ > #define ARM_CPU_CTRL 3, 0, 1, 0 > #define ARM_CPU_CTRL_SCTLR_EL1 0 > > +#define ARM_VCPU_PTRAUTH_FEATURE ((1UL << KVM_ARM_VCPU_PTRAUTH_ADDRESS) \ > + | (1UL << KVM_ARM_VCPU_PTRAUTH_GENERIC)) > #endif /* KVM__KVM_CPU_ARCH_H */ > diff --git a/arm/include/arm-common/kvm-config-arch.h b/arm/include/arm-common/kvm-config-arch.h > index 5734c46..1b4287d 100644 > --- a/arm/include/arm-common/kvm-config-arch.h > +++ b/arm/include/arm-common/kvm-config-arch.h > @@ -10,6 +10,8 @@ struct kvm_config_arch { > bool aarch32_guest; > bool has_pmuv3; > u64 kaslr_seed; > + bool enable_ptrauth; > + bool disable_ptrauth; > enum irqchip_type irqchip; > u64 fw_addr; > }; > diff --git a/arm/kvm-cpu.c b/arm/kvm-cpu.c > index 7780251..a45a649 100644 > --- a/arm/kvm-cpu.c > +++ b/arm/kvm-cpu.c > @@ -69,6 +69,17 @@ struct kvm_cpu *kvm_cpu__arch_init(struct kvm *kvm, unsigned long cpu_id) > } > > /* > + * Always enable Pointer Authentication if requested. If system supports > + * this extension then also enable it by default provided no disable > + * request present. > + */ > + if ((kvm->cfg.arch.enable_ptrauth) || > + (kvm__supports_extension(kvm, KVM_CAP_ARM_PTRAUTH_ADDRESS) && > + kvm__supports_extension(kvm, KVM_CAP_ARM_PTRAUTH_GENERIC) && > + !kvm->cfg.arch.disable_ptrauth)) I take it that: (1) Having both --enable-ptrauth and --disable-ptrauth present on the kvmtools command line is allowed (2) --enable-ptrauth takes precedence over --disable-ptrauth. Have you considered returning an error if both are present? Having --enable-ptrauth take precedence over --disable-ptrauth looks arbitrary to me (my expectations would have been for --disable-ptrauth to have precendece) and probably the user is doing something wrong if kvmtools is invoked with both arguments. > + vcpu_init.features[0] |= ARM_VCPU_PTRAUTH_FEATURE; > + > + /* > * If the preferred target ioctl is successful then > * use preferred target else try each and every target type > */ > diff --git a/include/linux/kvm.h b/include/linux/kvm.h > index 6d4ea4b..de1033b 100644 > --- a/include/linux/kvm.h > +++ b/include/linux/kvm.h > @@ -988,6 +988,8 @@ struct kvm_ppc_resize_hpt { > #define KVM_CAP_ARM_VM_IPA_SIZE 165 > #define KVM_CAP_MANUAL_DIRTY_LOG_PROTECT 166 > #define KVM_CAP_HYPERV_CPUID 167 > +#define KVM_CAP_ARM_PTRAUTH_ADDRESS 169 > +#define KVM_CAP_ARM_PTRAUTH_GENERIC 170 > > #ifdef KVM_CAP_IRQ_ROUTING > _______________________________________________ kvmarm mailing list kvmarm@lists.cs.columbia.edu https://lists.cs.columbia.edu/mailman/listinfo/kvmarm