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=-14.4 required=3.0 tests=DKIMWL_WL_MED,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_IN_DEF_DKIM_WL autolearn=unavailable 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 1368FC10F25 for ; Tue, 10 Mar 2020 01:05:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D220E20637 for ; Tue, 10 Mar 2020 01:05:39 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="gGjInPXd" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726389AbgCJBFi (ORCPT ); Mon, 9 Mar 2020 21:05:38 -0400 Received: from mail-lf1-f65.google.com ([209.85.167.65]:41846 "EHLO mail-lf1-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726202AbgCJBFi (ORCPT ); Mon, 9 Mar 2020 21:05:38 -0400 Received: by mail-lf1-f65.google.com with SMTP id q10so8677799lfo.8 for ; Mon, 09 Mar 2020 18:05:33 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc:content-transfer-encoding; bh=Ygq4rL6c32b9v1mGIXmpjeyzDhpEGmFslVXH83B3YQI=; b=gGjInPXdKZ+GQ+k0bdOIaoJ0g2Zi/WGSTdvmbRGcdW2F0cdc9UoYm8eeTpLoEgR9L9 4PN/93glZzGJPsOyfvJ5x3vagJ0yF+Rs9g+8SezQ7bwMfgv4zxzgM6FkcJWItNm33dq8 O8QVTWv5claEBO+Lc1bb5weQ3bhpi3i/dLxsUrZf8E1FtmPhbRSaMXTtxiiZyK3D0Qhz udW2aY9fzrx88P4JwvBoe+BbGk3qT9MQRdeU6st0GbuSahNUbvIMxzzZDBkXVmW13CJ+ RaYb2USVlCFmxB2q8t7KJHNyQ0RocEB+Ua+iv2mhK7lmSffgAAM+3tR0ZtfgSphgV3Tv eV2A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc:content-transfer-encoding; bh=Ygq4rL6c32b9v1mGIXmpjeyzDhpEGmFslVXH83B3YQI=; b=LPzDU1oBVAHqQB7Uku+3OITfGcGJSfCVQ7sfrXyDSQZ2QDxi48u31Fqvuj+MUcw/Xt ++YmkEf0UV/oBcFNWYZAjm6VyvcQoa48nHs9kiyebtXkAx33FNhsHd/1/fC7Laj50fQT Zz251COwjD6X43iK0x5+Cn12W117fSTYgCAhtVT29SWwp35MJmuJNWfPln1gcU2TcdX0 v82X7bKCPwiJAKOVCe4g3B43nGCwqgPvARN+1tvRQItDhGvhejhPhT7ZN1ioQDGOlDC0 zwlsp3lfQbTFYr0pzkBN3dgGp7QyxT26KiiZHt4/FGgyT1UaEETJ+z+9kBwqEJbsRhpd 6IvA== X-Gm-Message-State: ANhLgQ3ly5TLrRLjgeI43gWjb3rLOfktyuL9Zj5U35TtQ78BAAskvrXr WWBTS3W7O245WS0JhcZbxzV9AN/Dbqv+7fwyGJprYg== X-Google-Smtp-Source: ADFU+vtHcZhKvzzl5a2j6uSJBS313bp20fEBZQgxPfgMt2/YQwS8EYKnQRaBhZ3RLzo7gLKn4ZkwwECGmj3cQrvkRDI= X-Received: by 2002:a19:fc1d:: with SMTP id a29mr11058514lfi.209.1583802332298; Mon, 09 Mar 2020 18:05:32 -0700 (PDT) MIME-Version: 1.0 References: In-Reply-To: From: Steve Rutherford Date: Mon, 9 Mar 2020 18:04:56 -0700 Message-ID: Subject: Re: [PATCH 02/12] KVM: SVM: Add KVM_SEND_UPDATE_DATA command To: Ashish Kalra Cc: Paolo Bonzini , Thomas Gleixner , Ingo Molnar , "H. Peter Anvin" , Joerg Roedel , Borislav Petkov , Tom Lendacky , David Rientjes , X86 ML , KVM list , LKML Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Feb 12, 2020 at 5:15 PM Ashish Kalra wrote: > > From: Brijesh Singh > > The command is used for encrypting the guest memory region using the encr= yption > context created with KVM_SEV_SEND_START. > > Cc: Thomas Gleixner > Cc: Ingo Molnar > Cc: "H. Peter Anvin" > Cc: Paolo Bonzini > Cc: "Radim Kr=C4=8Dm=C3=A1=C5=99" > Cc: Joerg Roedel > Cc: Borislav Petkov > Cc: Tom Lendacky > Cc: x86@kernel.org > Cc: kvm@vger.kernel.org > Cc: linux-kernel@vger.kernel.org > Signed-off-by: Brijesh Singh > Signed-off-by: Ashish Kalra > --- > .../virt/kvm/amd-memory-encryption.rst | 24 ++++ > arch/x86/kvm/svm.c | 136 +++++++++++++++++- > include/uapi/linux/kvm.h | 9 ++ > 3 files changed, 165 insertions(+), 4 deletions(-) > > diff --git a/Documentation/virt/kvm/amd-memory-encryption.rst b/Documenta= tion/virt/kvm/amd-memory-encryption.rst > index 826911f41f3b..0f1c3860360f 100644 > --- a/Documentation/virt/kvm/amd-memory-encryption.rst > +++ b/Documentation/virt/kvm/amd-memory-encryption.rst > @@ -265,6 +265,30 @@ Returns: 0 on success, -negative on error > __u32 session_len; > }; > > +11. KVM_SEV_SEND_UPDATE_DATA > +---------------------------- > + > +The KVM_SEV_SEND_UPDATE_DATA command can be used by the hypervisor to en= crypt the > +outgoing guest memory region with the encryption context creating using > +KVM_SEV_SEND_START. > + > +Parameters (in): struct kvm_sev_send_update_data > + > +Returns: 0 on success, -negative on error > + > +:: > + > + struct kvm_sev_launch_send_update_data { > + __u64 hdr_uaddr; /* userspace address containing = the packet header */ > + __u32 hdr_len; > + > + __u64 guest_uaddr; /* the source memory region to b= e encrypted */ > + __u32 guest_len; > + > + __u64 trans_uaddr; /* the destition memory region = */ > + __u32 trans_len; > + }; > + > References > =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D > > diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c > index 3a7e2cac51de..ae97f774e979 100644 > --- a/arch/x86/kvm/svm.c > +++ b/arch/x86/kvm/svm.c > @@ -426,6 +426,7 @@ static DECLARE_RWSEM(sev_deactivate_lock); > static DEFINE_MUTEX(sev_bitmap_lock); > static unsigned int max_sev_asid; > static unsigned int min_sev_asid; > +static unsigned long sev_me_mask; > static unsigned long *sev_asid_bitmap; > static unsigned long *sev_reclaim_asid_bitmap; > #define __sme_page_pa(x) __sme_set(page_to_pfn(x) << PAGE_SHIFT) > @@ -1231,16 +1232,22 @@ static int avic_ga_log_notifier(u32 ga_tag) > static __init int sev_hardware_setup(void) > { > struct sev_user_data_status *status; > + int eax, ebx; > int rc; > > - /* Maximum number of encrypted guests supported simultaneously */ > - max_sev_asid =3D cpuid_ecx(0x8000001F); > + /* > + * Query the memory encryption information. > + * EBX: Bit 0:5 Pagetable bit position used to indicate encrypt= ion > + * (aka Cbit). > + * ECX: Maximum number of encrypted guests supported simultaneo= usly. > + * EDX: Minimum ASID value that should be used for SEV guest. > + */ > + cpuid(0x8000001f, &eax, &ebx, &max_sev_asid, &min_sev_asid); > > if (!max_sev_asid) > return 1; > > - /* Minimum ASID value that should be used for SEV guest */ > - min_sev_asid =3D cpuid_edx(0x8000001F); > + sev_me_mask =3D 1UL << (ebx & 0x3f); > > /* Initialize SEV ASID bitmaps */ > sev_asid_bitmap =3D bitmap_zalloc(max_sev_asid, GFP_KERNEL); > @@ -7262,6 +7269,124 @@ static int sev_send_start(struct kvm *kvm, struct= kvm_sev_cmd *argp) > return ret; > } > > +/* Userspace wants to query either header or trans length. */ > +static int > +__sev_send_update_data_query_lengths(struct kvm *kvm, struct kvm_sev_cmd= *argp, > + struct kvm_sev_send_update_data *par= ams) > +{ > + struct kvm_sev_info *sev =3D &to_kvm_svm(kvm)->sev_info; > + struct sev_data_send_update_data *data; > + int ret; > + > + data =3D kzalloc(sizeof(*data), GFP_KERNEL_ACCOUNT); > + if (!data) > + return -ENOMEM; > + > + data->handle =3D sev->handle; > + ret =3D sev_issue_cmd(kvm, SEV_CMD_SEND_UPDATE_DATA, data, &argp-= >error); > + > + params->hdr_len =3D data->hdr_len; > + params->trans_len =3D data->trans_len; > + > + if (copy_to_user((void __user *)(uintptr_t)argp->data, params, > + sizeof(struct kvm_sev_send_update_data))) > + ret =3D -EFAULT; > + > + kfree(data); > + return ret; > +} > + > +static int sev_send_update_data(struct kvm *kvm, struct kvm_sev_cmd *arg= p) > +{ > + struct kvm_sev_info *sev =3D &to_kvm_svm(kvm)->sev_info; > + struct sev_data_send_update_data *data; > + struct kvm_sev_send_update_data params; > + void *hdr, *trans_data; > + struct page **guest_page; > + unsigned long n; > + int ret, offset; > + > + if (!sev_guest(kvm)) > + return -ENOTTY; > + > + if (copy_from_user(¶ms, (void __user *)(uintptr_t)argp->data, > + sizeof(struct kvm_sev_send_update_data))) > + return -EFAULT; > + > + /* userspace wants to query either header or trans length */ > + if (!params.trans_len || !params.hdr_len) > + return __sev_send_update_data_query_lengths(kvm, argp, &p= arams); > + > + if (!params.trans_uaddr || !params.guest_uaddr || > + !params.guest_len || !params.hdr_uaddr) > + return -EINVAL; > + > + > + /* Check if we are crossing the page boundary */ > + offset =3D params.guest_uaddr & (PAGE_SIZE - 1); > + if ((params.guest_len + offset > PAGE_SIZE)) > + return -EINVAL; > + > + /* Pin guest memory */ > + guest_page =3D sev_pin_memory(kvm, params.guest_uaddr & PAGE_MASK= , > + PAGE_SIZE, &n, 0); > + if (!guest_page) > + return -EFAULT; > + > + /* allocate memory for header and transport buffer */ > + ret =3D -ENOMEM; > + hdr =3D kmalloc(params.hdr_len, GFP_KERNEL_ACCOUNT); > + if (!hdr) > + goto e_unpin; > + > + trans_data =3D kmalloc(params.trans_len, GFP_KERNEL_ACCOUNT); > + if (!trans_data) > + goto e_free_hdr; > + > + data =3D kzalloc(sizeof(*data), GFP_KERNEL); > + if (!data) > + goto e_free_trans_data; > + > + data->hdr_address =3D __psp_pa(hdr); > + data->hdr_len =3D params.hdr_len; > + data->trans_address =3D __psp_pa(trans_data); > + data->trans_len =3D params.trans_len; > + > + /* The SEND_UPDATE_DATA command requires C-bit to be always set. = */ > + data->guest_address =3D (page_to_pfn(guest_page[0]) << PAGE_SHIFT= ) + > + offset; > + data->guest_address |=3D sev_me_mask; > + data->guest_len =3D params.guest_len; > + data->handle =3D sev->handle; > + > + ret =3D sev_issue_cmd(kvm, SEV_CMD_SEND_UPDATE_DATA, data, &argp-= >error); > + > + if (ret) > + goto e_free; > + > + /* copy transport buffer to user space */ > + if (copy_to_user((void __user *)(uintptr_t)params.trans_uaddr, > + trans_data, params.trans_len)) { > + ret =3D -EFAULT; > + goto e_unpin; > + } > + > + /* Copy packet header to userspace. */ > + ret =3D copy_to_user((void __user *)(uintptr_t)params.hdr_uaddr, = hdr, > + params.hdr_len); > + > +e_free: > + kfree(data); > +e_free_trans_data: > + kfree(trans_data); > +e_free_hdr: > + kfree(hdr); > +e_unpin: > + sev_unpin_memory(kvm, guest_page, n); > + > + return ret; > +} > + > static int svm_mem_enc_op(struct kvm *kvm, void __user *argp) > { > struct kvm_sev_cmd sev_cmd; > @@ -7306,6 +7431,9 @@ static int svm_mem_enc_op(struct kvm *kvm, void __u= ser *argp) > case KVM_SEV_SEND_START: > r =3D sev_send_start(kvm, &sev_cmd); > break; > + case KVM_SEV_SEND_UPDATE_DATA: > + r =3D sev_send_update_data(kvm, &sev_cmd); > + break; > default: > r =3D -EINVAL; > goto out; > diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h > index 17bef4c245e1..d9dc81bb9c55 100644 > --- a/include/uapi/linux/kvm.h > +++ b/include/uapi/linux/kvm.h > @@ -1570,6 +1570,15 @@ struct kvm_sev_send_start { > __u32 session_len; > }; > > +struct kvm_sev_send_update_data { > + __u64 hdr_uaddr; > + __u32 hdr_len; > + __u64 guest_uaddr; > + __u32 guest_len; > + __u64 trans_uaddr; > + __u32 trans_len; > +}; Input from others is welcome here, but I'd put the padding in intentionally (explicitly fill in the reserved u8s between *_len and *_uaddr). I had to double check that this pattern was intentional and matched the SEV spec. > + > #define KVM_DEV_ASSIGN_ENABLE_IOMMU (1 << 0) > #define KVM_DEV_ASSIGN_PCI_2_3 (1 << 1) > #define KVM_DEV_ASSIGN_MASK_INTX (1 << 2) > -- > 2.17.1 > High level: this looks good. Same comments on documenting the magic parameters for querying as the prior patch, and also the -EFAULT behavior. Thanks, Steve