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 kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id A95B8C00140 for ; Tue, 2 Aug 2022 10:52:32 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 101386B0071; Tue, 2 Aug 2022 06:52:32 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 0B0EE6B0072; Tue, 2 Aug 2022 06:52:32 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id EBAA08E0001; Tue, 2 Aug 2022 06:52:31 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0014.hostedemail.com [216.40.44.14]) by kanga.kvack.org (Postfix) with ESMTP id DD2906B0071 for ; Tue, 2 Aug 2022 06:52:31 -0400 (EDT) Received: from smtpin06.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay04.hostedemail.com (Postfix) with ESMTP id ADD681A0EB5 for ; Tue, 2 Aug 2022 10:52:31 +0000 (UTC) X-FDA: 79754338902.06.9E2F8D2 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by imf24.hostedemail.com (Postfix) with ESMTP id 1C903180119 for ; Tue, 2 Aug 2022 10:52:29 +0000 (UTC) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 5AD866100D; Tue, 2 Aug 2022 10:52:29 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 39533C433D6; Tue, 2 Aug 2022 10:52:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1659437548; bh=BB8N6XMAgFrpqyoNWsZ0tvWL/E8gaH0CmpJ3bsTLESA=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=Bvp/+Xu4EENZ411axD3IpoH6BWTeWD1BzbWuRVN5T4JIsyGN98m/I6iqeOIMOvPZf 7XMy1I4CL2DKJzOUaGy0cyQmsIWNOBVHWy2GfZxVp9zxmcSm28ZK4iqJZrb+eHzqIs Q11jEvvd1pv/A11p8Bxu6LbziAs+W0Y7z+o9ogDb982wS0g6MBcomzggqEGDlFTS4z DyqylcDdc8j9+aaU0hr6K8pmaxLcwDe2AlCZTwXmiNSeTAGRKmVaOSVRtQD0aN29AU lKeSmSdIEHETCu3RD4bgLGTnhBQM9LWHIA1xC/Qn5hQQ4ALKMsQ4Mo5fcRcy0uuPUL mRBPApIdpG0UQ== Date: Tue, 2 Aug 2022 13:52:25 +0300 From: Jarkko Sakkinen To: Peter Gonda Cc: Ashish Kalra , the arch/x86 maintainers , LKML , kvm list , linux-coco@lists.linux.dev, linux-mm@kvack.org, Linux Crypto Mailing List , Thomas Gleixner , Ingo Molnar , Joerg Roedel , "Lendacky, Thomas" , "H. 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Shutemov" , Andi Kleen , Tony Luck , Marc Orr , Sathyanarayanan Kuppuswamy , Alper Gun , "Dr. David Alan Gilbert" Subject: Re: [PATCH Part2 v6 13/49] crypto:ccp: Provide APIs to issue SEV-SNP commands Message-ID: References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1659437550; a=rsa-sha256; cv=none; b=7vBPRx7TdNXrt/EpeAg3eMehjS0MrApF3ZvlfX4MC2mWl2DVMoXvps3PO/KSYOk48lsb15 PuD+nMS8FqmFNspcKiqUipX+CSTnpCJXk1pH8POLkVXlo3G6sM1XNRg2vrXgw2KCqNQ/UU woxMaxV/OaejQB7bjks8gr9gx/0s4ys= ARC-Authentication-Results: i=1; imf24.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b="Bvp/+Xu4"; spf=pass (imf24.hostedemail.com: domain of jarkko@kernel.org designates 139.178.84.217 as permitted sender) smtp.mailfrom=jarkko@kernel.org; dmarc=pass (policy=none) header.from=kernel.org ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1659437550; h=from:from:sender: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:dkim-signature; bh=hO8SP5Wf3AuZJCi6LRgV6NrmDD/DHOR69RFsZpsDbdo=; b=FF9y0X5shiYiJwci7BQYQnAjonuWLRRP44Ytau/0NbUd07I/acUKZz2hXukTMu+I0nevMJ S0CBV8K9K24IWD0ybprKrBsj2OhQIexhTGGCy1mrPJUCddAEBitqYlGWeJtESOKXT7Y+Iy a1z4zsQ238sKHPbzT3PNWOKSBOyB8Xc= X-Stat-Signature: q5pn9adpu4rdc1bzeinsabr38hxh19op X-Rspamd-Queue-Id: 1C903180119 X-Rspam-User: Authentication-Results: imf24.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b="Bvp/+Xu4"; spf=pass (imf24.hostedemail.com: domain of jarkko@kernel.org designates 139.178.84.217 as permitted sender) smtp.mailfrom=jarkko@kernel.org; dmarc=pass (policy=none) header.from=kernel.org X-Rspamd-Server: rspam03 X-HE-Tag: 1659437549-295576 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Tue, Jun 21, 2022 at 03:43:13PM -0600, Peter Gonda wrote: > ( > > On Mon, Jun 20, 2022 at 5:05 PM Ashish Kalra wrote: > > > > From: Brijesh Singh > > > > Provide the APIs for the hypervisor to manage an SEV-SNP guest. The > > commands for SEV-SNP is defined in the SEV-SNP firmware specification. > > > > Signed-off-by: Brijesh Singh > > --- > > drivers/crypto/ccp/sev-dev.c | 24 ++++++++++++ > > include/linux/psp-sev.h | 73 ++++++++++++++++++++++++++++++++++++ > > 2 files changed, 97 insertions(+) > > > > diff --git a/drivers/crypto/ccp/sev-dev.c b/drivers/crypto/ccp/sev-dev.c > > index f1173221d0b9..35d76333e120 100644 > > --- a/drivers/crypto/ccp/sev-dev.c > > +++ b/drivers/crypto/ccp/sev-dev.c > > @@ -1205,6 +1205,30 @@ int sev_guest_df_flush(int *error) > > } > > EXPORT_SYMBOL_GPL(sev_guest_df_flush); > > > > +int snp_guest_decommission(struct sev_data_snp_decommission *data, int *error) > > +{ > > + return sev_do_cmd(SEV_CMD_SNP_DECOMMISSION, data, error); > > +} > > +EXPORT_SYMBOL_GPL(snp_guest_decommission); > > + > > +int snp_guest_df_flush(int *error) > > +{ > > + return sev_do_cmd(SEV_CMD_SNP_DF_FLUSH, NULL, error); > > +} > > +EXPORT_SYMBOL_GPL(snp_guest_df_flush); Nit: undocumented exported functions. Both need kdoc. > > Why not instead change sev_guest_df_flush() to be SNP aware? That way > callers get the right behavior without having to know if SNP is > enabled or not. > > int sev_guest_df_flush(int *error) > { > if (!psp_master || !psp_master->sev_data) > return -EINVAL; > > if (psp_master->sev_data->snp_inited) > return sev_do_cmd(SEV_CMD_SNP_DF_FLUSH, NULL, error); > > return sev_do_cmd(SEV_CMD_DF_FLUSH, NULL, error); > } Because it serves no purpose to fuse them into one, and is only more obfuscated (and also undocumented). Two exported symbols can be traced also separately with ftrace/kprobes. Degrading transparency is not great idea IMHO. BR, Jarkko