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=-13.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham 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 20205C433C1 for ; Tue, 30 Mar 2021 09:26:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 917EF61874 for ; Tue, 30 Mar 2021 09:26:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231665AbhC3J0C (ORCPT ); Tue, 30 Mar 2021 05:26:02 -0400 Received: from mga07.intel.com ([134.134.136.100]:14577 "EHLO mga07.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230224AbhC3JZq (ORCPT ); Tue, 30 Mar 2021 05:25:46 -0400 IronPort-SDR: pzo9ssN3ggQoW2SB6NE6i/6YVYLilYBfAAHxVJpTq73KpT765oo7cOzxHO8L3GjxYDVS2wXF90 LNwCT8G6rdIw== X-IronPort-AV: E=McAfee;i="6000,8403,9938"; a="255720478" X-IronPort-AV: E=Sophos;i="5.81,290,1610438400"; d="asc'?scan'208";a="255720478" Received: from fmsmga002.fm.intel.com ([10.253.24.26]) by orsmga105.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 30 Mar 2021 02:25:46 -0700 IronPort-SDR: l+QCd94oY5/e9k1noc0scK7J8fCi0R+JAoZ4CRp5aNvZHvzeuRznn9angGqC2ujepaYDLgGKPn FBCtKVjs1y9Q== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.81,290,1610438400"; d="asc'?scan'208";a="445032237" Received: from zhen-hp.sh.intel.com (HELO zhen-hp) ([10.239.160.147]) by fmsmga002.fm.intel.com with ESMTP; 30 Mar 2021 02:25:44 -0700 Date: Tue, 30 Mar 2021 17:08:28 +0800 From: Zhenyu Wang To: Alex Williamson Cc: kvm@vger.kernel.org, intel-gfx@lists.freedesktop.org, Swee Yee Fonn Subject: Re: [PATCH v5] vfio/pci: Add support for opregion v2.1+ Message-ID: <20210330090828.GL1551@zhen-hp.sh.intel.com> Reply-To: Zhenyu Wang References: <20210302130220.9349-1-fred.gao@intel.com> <20210325170953.24549-1-fred.gao@intel.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="cGfB/trNgB3WtPHu" Content-Disposition: inline In-Reply-To: <20210325170953.24549-1-fred.gao@intel.com> Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org --cGfB/trNgB3WtPHu Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On 2021.03.26 01:09:53 +0800, Fred Gao wrote: > Before opregion version 2.0 VBT data is stored in opregion mailbox #4, > but when VBT data exceeds 6KB size and cannot be within mailbox #4 > then from opregion v2.0+, Extended VBT region, next to opregion is > used to hold the VBT data, so the total size will be opregion size plus > extended VBT region size. >=20 > Since opregion v2.0 with physical host VBT address would not be > practically available for end user and guest can not directly access > host physical address, so it is not supported. >=20 > Cc: Zhenyu Wang > Signed-off-by: Swee Yee Fonn > Signed-off-by: Fred Gao > --- Reviewed-by: Zhenyu Wang Hi, Alex, pls let us know if you have other concern to merge this one. Thanks! > drivers/vfio/pci/vfio_pci_igd.c | 53 +++++++++++++++++++++++++++++++++ > 1 file changed, 53 insertions(+) >=20 > diff --git a/drivers/vfio/pci/vfio_pci_igd.c b/drivers/vfio/pci/vfio_pci_= igd.c > index e66dfb0178ed..228df565e9bc 100644 > --- a/drivers/vfio/pci/vfio_pci_igd.c > +++ b/drivers/vfio/pci/vfio_pci_igd.c > @@ -21,6 +21,10 @@ > #define OPREGION_SIZE (8 * 1024) > #define OPREGION_PCI_ADDR 0xfc > =20 > +#define OPREGION_RVDA 0x3ba > +#define OPREGION_RVDS 0x3c2 > +#define OPREGION_VERSION 0x16 > + > static size_t vfio_pci_igd_rw(struct vfio_pci_device *vdev, char __user = *buf, > size_t count, loff_t *ppos, bool iswrite) > { > @@ -58,6 +62,7 @@ static int vfio_pci_igd_opregion_init(struct vfio_pci_d= evice *vdev) > u32 addr, size; > void *base; > int ret; > + u16 version; > =20 > ret =3D pci_read_config_dword(vdev->pdev, OPREGION_PCI_ADDR, &addr); > if (ret) > @@ -83,6 +88,54 @@ static int vfio_pci_igd_opregion_init(struct vfio_pci_= device *vdev) > =20 > size *=3D 1024; /* In KB */ > =20 > + /* > + * Support opregion v2.1+ > + * When VBT data exceeds 6KB size and cannot be within mailbox #4, then > + * the Extended VBT region next to opregion is used to hold the VBT dat= a. > + * RVDA (Relative Address of VBT Data from Opregion Base) and RVDS > + * (Raw VBT Data Size) from opregion structure member are used to hold = the > + * address from region base and size of VBT data. RVDA/RVDS are not > + * defined before opregion 2.0. > + * > + * opregion 2.1+: RVDA is unsigned, relative offset from > + * opregion base, and should point to the end of opregion. > + * otherwise, exposing to userspace to allow read access to everything = between > + * the OpRegion and VBT is not safe. > + * RVDS is defined as size in bytes. > + * > + * opregion 2.0: rvda is the physical VBT address. > + * Since rvda is HPA it cannot be directly used in guest. > + * And it should not be practically available for end user,so it is not= supported. > + */ > + version =3D le16_to_cpu(*(__le16 *)(base + OPREGION_VERSION)); > + if (version >=3D 0x0200) { > + u64 rvda; > + u32 rvds; > + > + rvda =3D le64_to_cpu(*(__le64 *)(base + OPREGION_RVDA)); > + rvds =3D le32_to_cpu(*(__le32 *)(base + OPREGION_RVDS)); > + if (rvda && rvds) { > + /* no support for opregion v2.0 with physical VBT address */ > + if (version =3D=3D 0x0200) { > + memunmap(base); > + pci_err(vdev->pdev, > + "IGD assignment does not support opregion v2.0 with an extended VBT= region\n"); > + return -EINVAL; > + } > + > + if (rvda !=3D size) { > + memunmap(base); > + pci_err(vdev->pdev, > + "Extended VBT does not follow opregion on version 0x%04x\n", > + version); > + return -EINVAL; > + } > + > + /* region size for opregion v2.0+: opregion and VBT size. */ > + size +=3D rvds; > + } > + } > + > if (size !=3D OPREGION_SIZE) { > memunmap(base); > base =3D memremap(addr, size, MEMREMAP_WB); > --=20 > 2.24.1.1.gb6d4d82bd5 >=20 --cGfB/trNgB3WtPHu Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iF0EARECAB0WIQTXuabgHDW6LPt9CICxBBozTXgYJwUCYGLqiAAKCRCxBBozTXgY Jw4XAJkB32OoMxlYMVx5y6A1F3RW81GUkACeIdlFGwuDP1XG/QeFTVv4ZiDvySc= =KHHI -----END PGP SIGNATURE----- --cGfB/trNgB3WtPHu--