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 mm01.cs.columbia.edu (mm01.cs.columbia.edu [128.59.11.253]) by smtp.lore.kernel.org (Postfix) with ESMTP id 39139C4332F for ; Mon, 14 Mar 2022 19:59:37 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id AC76649EB2; Mon, 14 Mar 2022 15:59:36 -0400 (EDT) X-Virus-Scanned: at lists.cs.columbia.edu Authentication-Results: mm01.cs.columbia.edu (amavisd-new); dkim=softfail (fail, message has been altered) header.i=@google.com 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 nuh9OfZC-+mY; Mon, 14 Mar 2022 15:59:35 -0400 (EDT) Received: from mm01.cs.columbia.edu (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id 5EC5F49EE9; Mon, 14 Mar 2022 15:59:35 -0400 (EDT) Received: from localhost (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id 6BC9D49EB5 for ; Mon, 14 Mar 2022 15:59:34 -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 9HfMr9FHCXw8 for ; Mon, 14 Mar 2022 15:59:33 -0400 (EDT) Received: from mail-il1-f174.google.com (mail-il1-f174.google.com [209.85.166.174]) by mm01.cs.columbia.edu (Postfix) with ESMTPS id 2836249EB2 for ; Mon, 14 Mar 2022 15:59:33 -0400 (EDT) Received: by mail-il1-f174.google.com with SMTP id r2so6896180ilh.0 for ; Mon, 14 Mar 2022 12:59:33 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=KhNnP/oPOEf+AzAoi7FbFVFnff3zDauVn+R3czZgO30=; b=XLvy0a2P3yr/7QgZ7XMz4vy53ApIYN+UaK82GHgDQ3xtEeRMJaOGOuG2NBzVDDsczs gElxMFyo00E2THZcl/7wUoIInd0phepsqCVLF4ktfce/OL5We+yjBBwq4+/KbnAKdDs/ i8i11DhG4zSg8SmvsE6lTDr23OlmYpe8CEYCatPaheYkh6KcW0E8x2Z67gNTMyClFDkF 6y/NDv4N5ePxfgJCTLgrZm0Np/Cv+5hx1cxjqXiMcHyJ+Jgz73ZPg9D9AlK8u1TpnnRo M2dAkMParYP6FpJ1TqAN3Cl34l4/84E3t5Nn6+esqE2OtgU7+1jhwXzua3n1hSeHJ18n HhnQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=KhNnP/oPOEf+AzAoi7FbFVFnff3zDauVn+R3czZgO30=; b=zQYyL4vhiXVFqlLY/MLx6RcYgGWREa21zVg+TnIDt/RjCZ4iiHGqiQ7wyV8mA53B5i L55A+mjN+Mctky/Ph55QBY5y/lnv8xR5cae9zyraB2jNOKdPUj0dePUyoDeGSgNCpziO u6OvtFhQJ3ZSD1Rx+iXcexwNEBjms6GGxsvH1iIpjwxGNTHdX7FOpU2/IIbLN4zkIMFd wSFYGIakvIhmF4MPh5qS1yjlcb45viFJzZLMQPdceJidMT0ylBZb+9J5cB7pNf6WIrMG DoiuC2vlHaaLKDL4SINoO/w//HSbwJJwvdPSy9arzxBb5So1c00NxAbA49dvw+T9EtPo n4pg== X-Gm-Message-State: AOAM53114RaUjN6Fs9qql8LmFzRgAG4BxGnxeE/v19/TpNamAYiZSFee wT7SwmXy5aRYZ9yZMJtnZIeqEw== X-Google-Smtp-Source: ABdhPJz/yPGOPSHTvHZXLM/c6Q7JI6z6lCmpGsm8deY68JVPwct+uxdlkutPxjPpDeKxc+BLSWOk9A== X-Received: by 2002:a92:c088:0:b0:2c7:9421:3c7b with SMTP id h8-20020a92c088000000b002c794213c7bmr9146321ile.280.1647287972235; Mon, 14 Mar 2022 12:59:32 -0700 (PDT) Received: from google.com (194.225.68.34.bc.googleusercontent.com. [34.68.225.194]) by smtp.gmail.com with ESMTPSA id r15-20020a056e0219cf00b002c77a3f2a85sm6286928ill.6.2022.03.14.12.59.31 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 14 Mar 2022 12:59:31 -0700 (PDT) Date: Mon, 14 Mar 2022 19:59:28 +0000 From: Oliver Upton To: Raghavendra Rao Ananta Subject: Re: [PATCH v4 07/13] KVM: arm64: Add vendor hypervisor firmware register Message-ID: References: <20220224172559.4170192-1-rananta@google.com> <20220224172559.4170192-8-rananta@google.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20220224172559.4170192-8-rananta@google.com> Cc: kvm@vger.kernel.org, Will Deacon , Marc Zyngier , Peter Shier , linux-kernel@vger.kernel.org, Catalin Marinas , Paolo Bonzini , kvmarm@lists.cs.columbia.edu, linux-arm-kernel@lists.infradead.org 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="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: kvmarm-bounces@lists.cs.columbia.edu Sender: kvmarm-bounces@lists.cs.columbia.edu On Thu, Feb 24, 2022 at 05:25:53PM +0000, Raghavendra Rao Ananta wrote: > Introduce the firmware register to hold the vendor specific > hypervisor service calls (owner value 6) as a bitmap. The > bitmap represents the features that'll be enabled for the > guest, as configured by the user-space. Currently, this > includes support only for Precision Time Protocol (PTP), > represented by bit-0. > > The register is also added to the kvm_arm_vm_scope_fw_regs[] > list as it maintains its state per-VM. > > Signed-off-by: Raghavendra Rao Ananta > --- > arch/arm64/include/asm/kvm_host.h | 2 ++ > arch/arm64/include/uapi/asm/kvm.h | 4 ++++ > arch/arm64/kvm/guest.c | 1 + > arch/arm64/kvm/hypercalls.c | 22 +++++++++++++++++++++- > include/kvm/arm_hypercalls.h | 3 +++ > 5 files changed, 31 insertions(+), 1 deletion(-) > > diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h > index 318148b69279..d999456c4604 100644 > --- a/arch/arm64/include/asm/kvm_host.h > +++ b/arch/arm64/include/asm/kvm_host.h > @@ -106,10 +106,12 @@ struct kvm_arch_memory_slot { > * > * @hvc_std_bmap: Bitmap of standard secure service calls > * @hvc_std_hyp_bmap: Bitmap of standard hypervisor service calls > + * @hvc_vendor_hyp_bmap: Bitmap of vendor specific hypervisor service calls > */ > struct kvm_hvc_desc { > u64 hvc_std_bmap; > u64 hvc_std_hyp_bmap; > + u64 hvc_vendor_hyp_bmap; > }; > > struct kvm_arch { > diff --git a/arch/arm64/include/uapi/asm/kvm.h b/arch/arm64/include/uapi/asm/kvm.h > index 9a2caead7359..ed470bde13d8 100644 > --- a/arch/arm64/include/uapi/asm/kvm.h > +++ b/arch/arm64/include/uapi/asm/kvm.h > @@ -299,6 +299,10 @@ struct kvm_arm_copy_mte_tags { > #define KVM_REG_ARM_STD_HYP_BIT_PV_TIME BIT(0) > #define KVM_REG_ARM_STD_HYP_BMAP_BIT_MAX 0 /* Last valid bit */ > > +#define KVM_REG_ARM_VENDOR_HYP_BMAP KVM_REG_ARM_FW_BMAP_REG(2) > +#define KVM_REG_ARM_VENDOR_HYP_BIT_PTP BIT(0) > +#define KVM_REG_ARM_VENDOR_HYP_BMAP_BIT_MAX 0 /* Last valid bit */ > + > /* SVE registers */ > #define KVM_REG_ARM64_SVE (0x15 << KVM_REG_ARM_COPROC_SHIFT) > > diff --git a/arch/arm64/kvm/guest.c b/arch/arm64/kvm/guest.c > index c42426d6137e..fc3656f91aed 100644 > --- a/arch/arm64/kvm/guest.c > +++ b/arch/arm64/kvm/guest.c > @@ -67,6 +67,7 @@ static const u64 kvm_arm_vm_scope_fw_regs[] = { > KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2, > KVM_REG_ARM_STD_BMAP, > KVM_REG_ARM_STD_HYP_BMAP, > + KVM_REG_ARM_VENDOR_HYP_BMAP, > }; > > /** > diff --git a/arch/arm64/kvm/hypercalls.c b/arch/arm64/kvm/hypercalls.c > index ebc0cc26cf2e..5c5098c8f1f9 100644 > --- a/arch/arm64/kvm/hypercalls.c > +++ b/arch/arm64/kvm/hypercalls.c > @@ -79,6 +79,9 @@ static bool kvm_hvc_call_supported(struct kvm_vcpu *vcpu, u32 func_id) > case ARM_SMCCC_HV_PV_TIME_ST: > return kvm_arm_fw_reg_feat_enabled(hvc_desc->hvc_std_hyp_bmap, > KVM_REG_ARM_STD_HYP_BIT_PV_TIME); > + case ARM_SMCCC_VENDOR_HYP_KVM_PTP_FUNC_ID: > + return kvm_arm_fw_reg_feat_enabled(hvc_desc->hvc_vendor_hyp_bmap, > + KVM_REG_ARM_VENDOR_HYP_BIT_PTP); > default: > /* By default, allow the services that aren't listed here */ > return true; > @@ -162,7 +165,14 @@ int kvm_hvc_call_handler(struct kvm_vcpu *vcpu) > break; > case ARM_SMCCC_VENDOR_HYP_KVM_FEATURES_FUNC_ID: > val[0] = BIT(ARM_SMCCC_KVM_FUNC_FEATURES); > - val[0] |= BIT(ARM_SMCCC_KVM_FUNC_PTP); > + > + /* > + * The feature bits exposed to user-space doesn't include > + * ARM_SMCCC_KVM_FUNC_FEATURES. However, we expose this to > + * the guest as bit-0. Hence, left-shift the user-space > + * exposed bitmap by 1 to accommodate this. > + */ > + val[0] |= hvc_desc->hvc_vendor_hyp_bmap << 1; Having an off-by-one difference between the userspace and guest representations of this bitmap seems like it could be a source of bugs in the future. Its also impossible for the guest to completely hide the vendor range if it so chooses. Why not tie ARM_SMCCC_VENDOR_HYP_CALL_UID_FUNC_ID and ARM_SMCCC_VENDOR_HYP_KVM_FEATURES_FUNC_ID to BIT(0)? PTP would then become BIT(1). > break; > case ARM_SMCCC_VENDOR_HYP_KVM_PTP_FUNC_ID: > kvm_ptp_get_time(vcpu, val); > @@ -188,6 +198,7 @@ static const u64 kvm_arm_fw_reg_ids[] = { > KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2, > KVM_REG_ARM_STD_BMAP, > KVM_REG_ARM_STD_HYP_BMAP, > + KVM_REG_ARM_VENDOR_HYP_BMAP, > }; > > void kvm_arm_init_hypercalls(struct kvm *kvm) > @@ -196,6 +207,7 @@ void kvm_arm_init_hypercalls(struct kvm *kvm) > > hvc_desc->hvc_std_bmap = ARM_SMCCC_STD_FEATURES; > hvc_desc->hvc_std_hyp_bmap = ARM_SMCCC_STD_HYP_FEATURES; > + hvc_desc->hvc_vendor_hyp_bmap = ARM_SMCCC_VENDOR_HYP_FEATURES; > } > > int kvm_arm_get_fw_num_regs(struct kvm_vcpu *vcpu) > @@ -285,6 +297,9 @@ int kvm_arm_get_fw_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg) > case KVM_REG_ARM_STD_HYP_BMAP: > val = READ_ONCE(hvc_desc->hvc_std_hyp_bmap); > break; > + case KVM_REG_ARM_VENDOR_HYP_BMAP: > + val = READ_ONCE(hvc_desc->hvc_vendor_hyp_bmap); > + break; > default: > return -ENOENT; > } > @@ -311,6 +326,10 @@ static int kvm_arm_set_fw_reg_bmap(struct kvm_vcpu *vcpu, u64 reg_id, u64 val) > fw_reg_bmap = &hvc_desc->hvc_std_hyp_bmap; > fw_reg_features = ARM_SMCCC_STD_HYP_FEATURES; > break; > + case KVM_REG_ARM_VENDOR_HYP_BMAP: > + fw_reg_bmap = &hvc_desc->hvc_vendor_hyp_bmap; > + fw_reg_features = ARM_SMCCC_VENDOR_HYP_FEATURES; > + break; > default: > return -ENOENT; > } > @@ -416,6 +435,7 @@ int kvm_arm_set_fw_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg) > return 0; > case KVM_REG_ARM_STD_BMAP: > case KVM_REG_ARM_STD_HYP_BMAP: > + case KVM_REG_ARM_VENDOR_HYP_BMAP: > return kvm_arm_set_fw_reg_bmap(vcpu, reg_id, val); > default: > return -ENOENT; > diff --git a/include/kvm/arm_hypercalls.h b/include/kvm/arm_hypercalls.h > index a1cb6e839c74..91be758ca58e 100644 > --- a/include/kvm/arm_hypercalls.h > +++ b/include/kvm/arm_hypercalls.h > @@ -12,6 +12,9 @@ > #define ARM_SMCCC_STD_HYP_FEATURES \ > GENMASK_ULL(KVM_REG_ARM_STD_HYP_BMAP_BIT_MAX, 0) > > +#define ARM_SMCCC_VENDOR_HYP_FEATURES \ > + GENMASK_ULL(KVM_REG_ARM_VENDOR_HYP_BMAP_BIT_MAX, 0) > + > int kvm_hvc_call_handler(struct kvm_vcpu *vcpu); > > static inline u32 smccc_get_function(struct kvm_vcpu *vcpu) > -- > 2.35.1.473.g83b2b277ed-goog > _______________________________________________ kvmarm mailing list kvmarm@lists.cs.columbia.edu https://lists.cs.columbia.edu/mailman/listinfo/kvmarm