From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail02.groups.io (mail02.groups.io [66.175.222.108]) by spool.mail.gandi.net (Postfix) with ESMTPS id F06A0942184 for ; Tue, 12 Mar 2024 17:14:25 +0000 (UTC) DKIM-Signature: a=rsa-sha256; bh=q+wYpS3O4XBMmmwRwcAhM+Y7Ju1Xb8mIc5+2FghrOJ8=; c=relaxed/simple; d=groups.io; h=Message-ID:Date:MIME-Version:User-Agent:Subject:To:CC:References:From:In-Reply-To:Precedence:List-Subscribe:List-Help:Sender:List-Id:Mailing-List:Delivered-To:Resent-Date:Reply-To:List-Unsubscribe-Post:List-Unsubscribe:Content-Language:Content-Type:Content-Transfer-Encoding; s=20240206; t=1710263664; v=1; b=n5ZCCqxfB087x0iwNhB9WZuoK8O8hgO7XKmXu75IBXv9LiWkFAYoL68QrQLwgZ9qlulldD9J +t8DBmIZAhULQTbP/boxtbuXiG/kwE0BOJquL6mX5eArU6ODxwEharO8fUWeVNOn52YXP1yM0gy 6yZmnwcS6tjssdDDY1vRDbEURUX1H7WxnkoXEfshcKnd1gxfWbPOuB1vWXDcoTRmPtgsm7If+mH zFcJ9RR4x8IVdjxh/sgi4q3fZRlLACV9WO0B3/IBZD8maLVrc1hrS+l10LwrygA7XdHAevytgU4 bsNBtUiYa7WbPb1dEqmw1wX3ePd/Ig2ZlhM3dyPGRVR7g== X-Received: by 127.0.0.2 with SMTP id blHHYY7687511x3pHGja6ehn; Tue, 12 Mar 2024 10:14:24 -0700 X-Received: from mx0a-0031df01.pphosted.com (mx0a-0031df01.pphosted.com [205.220.168.131]) by mx.groups.io with SMTP id smtpd.web10.2132.1710263664020771213 for ; Tue, 12 Mar 2024 10:14:24 -0700 X-Received: from pps.filterd (m0279867.ppops.net [127.0.0.1]) by mx0a-0031df01.pphosted.com (8.17.1.24/8.17.1.24) with ESMTP id 42C9ikik029515; Tue, 12 Mar 2024 17:14:19 GMT X-Received: from nasanppmta04.qualcomm.com (i-global254.qualcomm.com [199.106.103.254]) by mx0a-0031df01.pphosted.com (PPS) with ESMTPS id 3wtmpd10vr-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 12 Mar 2024 17:14:19 +0000 (GMT) X-Received: from nasanex01c.na.qualcomm.com (nasanex01c.na.qualcomm.com [10.45.79.139]) by NASANPPMTA04.qualcomm.com (8.17.1.5/8.17.1.5) with ESMTPS id 42CHEI6b018494 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 12 Mar 2024 17:14:18 GMT X-Received: from [10.110.22.181] (10.80.80.8) by nasanex01c.na.qualcomm.com (10.45.79.139) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1118.40; Tue, 12 Mar 2024 10:14:18 -0700 Message-ID: <361be442-f490-4d05-8fec-aa8a294bb3b8@quicinc.com> Date: Tue, 12 Mar 2024 10:14:17 -0700 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [edk2-devel] [PATCH 1/1] EmbeddedPkg/NonCoherentIoMmuDxe: Make SetAttributes always succeed To: Ard Biesheuvel CC: , , References: <20240312151716.2154180-1-ardb+git@google.com> <74a4fb99-5d29-44ac-93bd-caea7367d08e@quicinc.com> From: "Leif Lindholm" In-Reply-To: X-Originating-IP: [10.80.80.8] X-ClientProxiedBy: nasanex01b.na.qualcomm.com (10.46.141.250) To nasanex01c.na.qualcomm.com (10.45.79.139) X-QCInternal: smtphost X-Proofpoint-GUID: ZL7zXzcJzqeBxk5zVhMce_UaEucOvSdW X-Proofpoint-ORIG-GUID: ZL7zXzcJzqeBxk5zVhMce_UaEucOvSdW Precedence: Bulk List-Subscribe: List-Help: Sender: devel@edk2.groups.io List-Id: Mailing-List: list devel@edk2.groups.io; contact devel+owner@edk2.groups.io Resent-Date: Tue, 12 Mar 2024 10:14:24 -0700 Reply-To: devel@edk2.groups.io,quic_llindhol@quicinc.com List-Unsubscribe-Post: List-Unsubscribe=One-Click List-Unsubscribe: X-Gm-Message-State: CK14yABqwlv4jhZhJ9qP7jVPx7686176AA= Content-Language: en-GB Content-Type: text/plain; charset="UTF-8"; format=flowed Content-Transfer-Encoding: quoted-printable X-GND-Status: LEGIT Authentication-Results: spool.mail.gandi.net; dkim=pass header.d=groups.io header.s=20240206 header.b=n5ZCCqxf; dmarc=fail reason="SPF not aligned (relaxed), DKIM not aligned (relaxed)" header.from=quicinc.com (policy=none); spf=pass (spool.mail.gandi.net: domain of bounce@groups.io designates 66.175.222.108 as permitted sender) smtp.mailfrom=bounce@groups.io On 2024-03-12 09:58, Ard Biesheuvel wrote: > On Tue, 12 Mar 2024 at 17:56, Leif Lindholm w= rote: >> >> On 2024-03-12 09:50, Ard Biesheuvel wrote: >>> On Tue, 12 Mar 2024 at 17:38, Leif Lindholm = wrote: >>>> >>>> On 2024-03-12 08:17, Ard Biesheuvel wrote: >>>>> From: Ard Biesheuvel >>>>> >>>>> NonCoherentIoMmuSetAttribute() does nothing except return >>>>> EFI_UNSUPPORTED. This was fine when it was introduced, but now, the P= CI >>>>> bus driver will fail a PCI I/O Map() operation if the SetAttributes >>>>> fails. >>>>> >>>>> So return EFI_SUCCESS instead. >>>> >>>> It's unclear to me why this change is safe (looking forward). >>>> Does NonCoherentIoMmuDxe also imply no IoMmu actually exists? >>>> >>> >>> Basically. NonCoherentIoMmuDxe is just a vehicle to allow >>> NonCoherentDmaLib to be plugged into the PCI host bridge driver. It is >>> not intended to ever do anything more than that. >> >> Not that it needs to happen for this >> (Reviewed-by: Leif Lindholm ) >> but maybe we ought to consider renaming it then? >> DummyIoMmuDxe? >=20 > Fair point. Or PassThroughIoMmuDxe perhaps? Works for me. Or, hmm... Is there a risk that sounds a bit like a driver that actively configures=20 IoMmus into passthrough mode? / Leif -=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D- Groups.io Links: You receive all messages sent to this group. View/Reply Online (#116697): https://edk2.groups.io/g/devel/message/116697 Mute This Topic: https://groups.io/mt/104886877/7686176 Group Owner: devel+owner@edk2.groups.io Unsubscribe: https://edk2.groups.io/g/devel/unsub [rebecca@openfw.io] -=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-