From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:40529) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1g08yM-0005Uo-Qz for qemu-devel@nongnu.org; Wed, 12 Sep 2018 13:30:39 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1g08yI-0005WU-8n for qemu-devel@nongnu.org; Wed, 12 Sep 2018 13:30:38 -0400 Received: from mx.dal1.terarocket.io ([108.61.222.170]:43116) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1g08yH-0005W7-VG for qemu-devel@nongnu.org; Wed, 12 Sep 2018 13:30:34 -0400 MIME-Version: 1.0 Date: Wed, 12 Sep 2018 17:30:29 +0000 From: "Alexander von Gluck IV" Message-ID: <72e9368e256e81fd69e3f6c65e6dd435@unixzen.com> Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Subject: [Qemu-devel] Debugging PCI Enhanced Allocation - IOMMU of a bridge? List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: alex.williamson@redhat.com, mst@redhat.com Good morning!=0A=0AI'm working through adding support (or at least ignori= ng) PCI Enhance Allocation devices under Haiku.=0AWe run into one of thes= e devices, and crash at boot due to attempting to read an invalid address= .=0A=0AOur testing showed that with a USB C dongle plugged in, we don't c= rash. Without it plugged in we get=0Ainvalid addresses from PCI=0A=0A(for= a long-drawn out debug ticket, see https://dev.haiku-os.org/ticket/12885= )=0ASo, i'm trying to see if I can emulate a PCI bridge with EA under QE= MU, I found this patch, but it seems it wasn't accepted: https://lists= .gnu.org/archive/html/qemu-devel/2015-05/msg02073.html (https://lists.gnu= .org/archive/html/qemu-devel/2015-05/msg02073.html)=0A=0AMy other thought= is since I have access to two laptops implementing this, I could attach = the bridge to=0Aqemu via iommu, but the new vfio stuff doesn't seem to wo= rk with bridges. :-| Anyone know of a way to: * emulate a PCI EA in qe= mu. * attach the local PCI EA bridge to qemu to troubleshoot using real = hardware. For context, here is the suspect EA device:=0A(no USB C dongle= )=0A$ lspci -tvnn=0A-[0000:00]-+-00.0 Intel Corporation Xeon E3-1200 v5/E= 3-1500 v5/6th Gen Core Processor Host Bridge/DRAM Registers [8086:1910]= =0A +-1d.6-[06-3e]--=0A=0Avs=0A=0A(USB C dongle)=0A$ lspci -tvnn=0A-[0000= :00]-+-00.0 Intel Corporation Skylake Host Bridge/DRAM Registers [8086:19= 04]=0A +-1d.6-[06-3e]----00.0-[07-3e]--+-00.0-[08]--=0A | +-01.0-[09-3d]-= -=0A | -02.0-[3e]----00.0 Intel Corporation DSL6340 USB 3.1 Controller [A= lpine Ridge] [8086:15b5]=0AThe bride is at 1d.6 in it's own IOMMU group:= =0A=0AIOMMU group 12=0A 00:1d.6 PCI bridge [0604]: Intel Corporation 100 = Series/C230 Series Chipset Family PCI Express Root Port #15 [8086:a11e] (= rev f1)=0A=0A -- Alex