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=-4.0 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED autolearn=no 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 6941DC433DF for ; Tue, 11 Aug 2020 00:52:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 44E0520734 for ; Tue, 11 Aug 2020 00:52:13 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=amacapital-net.20150623.gappssmtp.com header.i=@amacapital-net.20150623.gappssmtp.com header.b="jXfYK3Ob" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727925AbgHKAwN (ORCPT ); Mon, 10 Aug 2020 20:52:13 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38134 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727039AbgHKAwM (ORCPT ); Mon, 10 Aug 2020 20:52:12 -0400 Received: from mail-pl1-x641.google.com (mail-pl1-x641.google.com [IPv6:2607:f8b0:4864:20::641]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A1540C061756 for ; Mon, 10 Aug 2020 17:52:12 -0700 (PDT) Received: by mail-pl1-x641.google.com with SMTP id p1so5992903pls.4 for ; Mon, 10 Aug 2020 17:52:12 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=amacapital-net.20150623.gappssmtp.com; s=20150623; h=content-transfer-encoding:from:mime-version:subject:date:message-id :references:cc:in-reply-to:to; bh=kHhE3KrqVSlK0oFrxg5v1Xt0D8wngSHyqdeNULILsHk=; b=jXfYK3ObsyUOF4jk+4aHI3bUqrwfSAsPwkkEo1V5liUVdrTCMjNvieOlq8Bpc7OKGJ hhNCTr+1YJAutODjagxDTxqwQ4DYSHaSy3crmF1RpydqxJFddvI4zFY8Dj8u5J+vHane G96bX15HcRFwp7IOdK4VVuUDrCAU923wDnlbZBm9jwA1fM7lnjw9m7P97T9ToXQqSH1U 2FfQerKg0X3gF3su+FFfQjdPBm7tDXGIq0OmJAm6HDCCduQou3LCsfmfTA083Mko18hH gZUM85Ribs45yLd7GwUa+FLIEtiU/lrmz881fxedsyxp/3UvjVNwZRBXKJaEGSU7WiA/ VPCA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:content-transfer-encoding:from:mime-version :subject:date:message-id:references:cc:in-reply-to:to; bh=kHhE3KrqVSlK0oFrxg5v1Xt0D8wngSHyqdeNULILsHk=; b=K2zRI523/HUic7dVFGHroGjSM3n4V8JBRsk650KKfBxLZ87PdCEQGT4iCQmBLgDBLV H9fAYwY8smsE3O6usnxjovntcjzCmDlxHx78+X5fkAypIOZHj+0f/Oruhd82ly417iYS /5jjxfMfwFhZ/1R3nkKJ9tZq+utTwj4szsQM/7TdY4fMfxnb0rn8hmuUyUVZ60j/wbk/ BalPbHdCitbWvpKME8vqVwV/NEbx1VAJ7lb+cs/yD+H+1FCSgPabgoicSFNcSPnoFOQG A4yIXg6UWWW2rwN2d1qE8dwJurKb259RPj5RE1GK0rI59p57R5v7gnSLDaxnnLaNw2fQ aYvQ== X-Gm-Message-State: AOAM530vt1YrIaJ0B3DI7tfGF3bxqayL2vRkclEAKY8w48dux4//VZ+z 2rcFB7FkbjMa3pfWbIQFbjZrAQ== X-Google-Smtp-Source: ABdhPJxwJs3I5b3pGXSul2QL1pi5Yk6chwUGXOPyMrzXwEwUOvwrnP8hZHRLjI+SbL4tdb/gyJ4i9A== X-Received: by 2002:a17:90a:eb18:: with SMTP id j24mr2000716pjz.76.1597107132033; Mon, 10 Aug 2020 17:52:12 -0700 (PDT) Received: from ?IPv6:2600:1010:b06c:4273:ede1:e14c:cb3e:8ecb? ([2600:1010:b06c:4273:ede1:e14c:cb3e:8ecb]) by smtp.gmail.com with ESMTPSA id np4sm679997pjb.4.2020.08.10.17.52.10 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Mon, 10 Aug 2020 17:52:11 -0700 (PDT) Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable From: Andy Lutomirski Mime-Version: 1.0 (1.0) Subject: Re: [PATCH v36 21/24] x86/vdso: Implement a vDSO for Intel SGX enclave call Date: Mon, 10 Aug 2020 17:52:09 -0700 Message-Id: References: <20200810234837.GH14724@linux.intel.com> Cc: Andy Lutomirski , Nathaniel McCallum , Jarkko Sakkinen , X86 ML , linux-sgx@vger.kernel.org, LKML , Jethro Beekman , Cedric Xing , Andrew Morton , Andy Shevchenko , asapek@google.com, Borislav Petkov , chenalexchen@google.com, Conrad Parker , cyhanish@google.com, Dave Hansen , "Huang, Haitao" , Josh Triplett , "Huang, Kai" , "Svahn, Kai" , Keith Moyer , Christian Ludloff , Neil Horman , Patrick Uiterwijk , David Rientjes , Thomas Gleixner , yaozhangx@google.com In-Reply-To: <20200810234837.GH14724@linux.intel.com> To: Sean Christopherson X-Mailer: iPhone Mail (17G68) Sender: linux-sgx-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-sgx@vger.kernel.org > On Aug 10, 2020, at 4:48 PM, Sean Christopherson wrote: >=20 > =EF=BB=BFOn Mon, Aug 10, 2020 at 04:08:46PM -0700, Andy Lutomirski wrote: >> What am I missing? I still don't really understand why we are >> supporting this mechanism at all. Just the asm code to invoke the >> callback seems to be about half of the entire function. >=20 > Because the Intel SDK (and other SDKs?) wants to use the host stack to pas= s > parameters out of the enclave. Ugh, right. I forgot about that particular abomination. I suppose that passing a context pointer would be reasonable.=