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=-10.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 E0EFFC41537 for ; Fri, 27 Aug 2021 17:43:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C315960F44 for ; Fri, 27 Aug 2021 17:43:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237091AbhH0Ro2 (ORCPT ); Fri, 27 Aug 2021 13:44:28 -0400 Received: from mail.skyhub.de ([5.9.137.197]:41610 "EHLO mail.skyhub.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230035AbhH0Ro1 (ORCPT ); Fri, 27 Aug 2021 13:44:27 -0400 Received: from zn.tnic (p200300ec2f111700cf40790d4c46ba75.dip0.t-ipconnect.de [IPv6:2003:ec:2f11:1700:cf40:790d:4c46:ba75]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.skyhub.de (SuperMail on ZX Spectrum 128k) with ESMTPSA id 887F01EC0537; Fri, 27 Aug 2021 19:43:32 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=alien8.de; s=dkim; t=1630086212; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:in-reply-to:in-reply-to: references:references; bh=ksK72yJ3wySU/4v/Z0DqBPrVhHFzU36FDKHslitFLfs=; b=CnZ7xUnX3NltwfLtDCZBosHAKgNAyTK6OO9/+F36exMtD43KMTmwz5jrW/9RSQnPafC7ex V1OGb6wIYQBciY/0KWALp0WLIhIXvQulT61+QAsnWfQGKgl4LeO5QriszIWX+fC3A8nbVk 8wnxrv59MVzTd3bMXDCEcNqxd9X6sbU= Date: Fri, 27 Aug 2021 19:44:09 +0200 From: Borislav Petkov To: Brijesh Singh Cc: x86@kernel.org, linux-kernel@vger.kernel.org, kvm@vger.kernel.org, linux-efi@vger.kernel.org, platform-driver-x86@vger.kernel.org, linux-coco@lists.linux.dev, linux-mm@kvack.org, Thomas Gleixner , Ingo Molnar , Joerg Roedel , Tom Lendacky , "H. Peter Anvin" , Ard Biesheuvel , Paolo Bonzini , Sean Christopherson , Vitaly Kuznetsov , Wanpeng Li , Jim Mattson , Andy Lutomirski , Dave Hansen , Sergio Lopez , Peter Gonda , Peter Zijlstra , Srinivas Pandruvada , David Rientjes , Dov Murik , Tobin Feldman-Fitzthum , Michael Roth , Vlastimil Babka , "Kirill A . Shutemov" , Andi Kleen , tony.luck@intel.com, marcorr@google.com, sathyanarayanan.kuppuswamy@linux.intel.com Subject: Re: [PATCH Part1 v5 33/38] x86/sev: Provide support for SNP guest request NAEs Message-ID: References: <20210820151933.22401-1-brijesh.singh@amd.com> <20210820151933.22401-34-brijesh.singh@amd.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20210820151933.22401-34-brijesh.singh@amd.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Aug 20, 2021 at 10:19:28AM -0500, Brijesh Singh wrote: > +int snp_issue_guest_request(int type, struct snp_guest_request_data *input, unsigned long *fw_err) > +{ > + struct ghcb_state state; > + unsigned long id, flags; > + struct ghcb *ghcb; > + int ret; > + > + if (!sev_feature_enabled(SEV_SNP)) > + return -ENODEV; > + > + local_irq_save(flags); > + > + ghcb = __sev_get_ghcb(&state); > + if (!ghcb) { > + ret = -EIO; > + goto e_restore_irq; > + } > + > + vc_ghcb_invalidate(ghcb); > + > + if (type == GUEST_REQUEST) { > + id = SVM_VMGEXIT_GUEST_REQUEST; > + } else if (type == EXT_GUEST_REQUEST) { > + id = SVM_VMGEXIT_EXT_GUEST_REQUEST; > + ghcb_set_rax(ghcb, input->data_gpa); > + ghcb_set_rbx(ghcb, input->data_npages); Hmmm, now I'm not sure. We did enum psc_op where you simply pass in the op directly to the hardware because the enum uses the same numbers as the actual command. But here that @type thing is simply used to translate to the SVM_VMGEXIT thing. So maybe you don't need it here and you can hand in the exit_code directly: int snp_issue_guest_request(u64 exit_code, struct snp_guest_request_data *input, unsigned long *fw_err) which you then pass in directly to... > + } else { > + ret = -EINVAL; > + goto e_put; > + } > + > + ret = sev_es_ghcb_hv_call(ghcb, NULL, id, input->req_gpa, input->resp_gpa); ... this guy here: ret = sev_es_ghcb_hv_call(ghcb, NULL, exit_code, input->req_gpa, input->resp_gpa); > + if (ret) > + goto e_put; > + > + if (ghcb->save.sw_exit_info_2) { > + /* Number of expected pages are returned in RBX */ > + if (id == EXT_GUEST_REQUEST && > + ghcb->save.sw_exit_info_2 == SNP_GUEST_REQ_INVALID_LEN) > + input->data_npages = ghcb_get_rbx(ghcb); > + > + if (fw_err) > + *fw_err = ghcb->save.sw_exit_info_2; > + > + ret = -EIO; > + } > + > +e_put: > + __sev_put_ghcb(&state); > +e_restore_irq: > + local_irq_restore(flags); > + > + return ret; > +} > +EXPORT_SYMBOL_GPL(snp_issue_guest_request); > diff --git a/include/linux/sev-guest.h b/include/linux/sev-guest.h Why is this a separate header in the include/linux/ namespace? Is SNP available on something which is !x86, all of a sudden? > new file mode 100644 > index 000000000000..24dd17507789 > --- /dev/null > +++ b/include/linux/sev-guest.h > @@ -0,0 +1,48 @@ > +/* SPDX-License-Identifier: GPL-2.0-only */ > +/* > + * AMD Secure Encrypted Virtualization (SEV) guest driver interface > + * > + * Copyright (C) 2021 Advanced Micro Devices, Inc. > + * > + * Author: Brijesh Singh > + * > + */ > + > +#ifndef __LINUX_SEV_GUEST_H_ > +#define __LINUX_SEV_GUEST_H_ > + > +#include > + > +enum vmgexit_type { > + GUEST_REQUEST, > + EXT_GUEST_REQUEST, > + > + GUEST_REQUEST_MAX > +}; > + > +/* > + * The error code when the data_npages is too small. The error code > + * is defined in the GHCB specification. > + */ > +#define SNP_GUEST_REQ_INVALID_LEN 0x100000000ULL so basically BIT_ULL(32) > + > +struct snp_guest_request_data { "snp_req_data" I guess is shorter. And having "guest" in there is probably not needed because snp is always guest-related anyway. > + unsigned long req_gpa; > + unsigned long resp_gpa; > + unsigned long data_gpa; > + unsigned int data_npages; > +}; > + > +#ifdef CONFIG_AMD_MEM_ENCRYPT > +int snp_issue_guest_request(int vmgexit_type, struct snp_guest_request_data *input, > + unsigned long *fw_err); > +#else > + > +static inline int snp_issue_guest_request(int type, struct snp_guest_request_data *input, > + unsigned long *fw_err) > +{ > + return -ENODEV; > +} > + > +#endif /* CONFIG_AMD_MEM_ENCRYPT */ > +#endif /* __LINUX_SEV_GUEST_H__ */ > -- > 2.17.1 > -- Regards/Gruss, Boris. https://people.kernel.org/tglx/notes-about-netiquette