From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:38745) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dAfqg-0004KO-La for qemu-devel@nongnu.org; Tue, 16 May 2017 13:01:27 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1dAfqd-0008Fh-8G for qemu-devel@nongnu.org; Tue, 16 May 2017 13:01:26 -0400 Received: from mx1.redhat.com ([209.132.183.28]:47092) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1dAfqd-0008FY-2L for qemu-devel@nongnu.org; Tue, 16 May 2017 13:01:23 -0400 References: <1494838260-30439-1-git-send-email-peterx@redhat.com> <9a93009b-f909-3142-5bc5-915b9a10ed20@redhat.com> <28bdbe39-7520-28c1-e58e-ec9f7ed69bde@redhat.com> From: Maxime Coquelin Message-ID: Date: Tue, 16 May 2017 19:01:10 +0200 MIME-Version: 1.0 In-Reply-To: <28bdbe39-7520-28c1-e58e-ec9f7ed69bde@redhat.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH 0/4] exec: address space translation cleanups List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Paolo Bonzini , Peter Xu , qemu-devel@nongnu.org Cc: Jason Wang , "Michael S . Tsirkin" , David Gibson On 05/16/2017 06:54 PM, Paolo Bonzini wrote: > > > On 16/05/2017 18:51, Maxime Coquelin wrote: >>> >>> I faced the problem the old patch fixes when declaring and attaching >>> an IOMMU device, but booting the kernel with intel_iommu=off. >>> >>> I tested again with patches 1 & 4 of your series, and I confirm it >>> fixes the issue: >>> Tested-by: Maxime Coquelin >> >> I did some more testing with my "vhost-user IOMMU" setup, and the series >> actually breaks with IOMMU device attached, and intel_iommu=on. >> >> The main difference with the previous passing test is the guest RAM >> size. In the working setup, it is 2G of 2M hugepages, vs. 4G of 2M >> hugepages in the failing one. Note that I also reproduce with >> vhost-kernel backend. >> >> The error happens in the first vhost_device_iotlb_miss() call: >> qemu-system-x86_64: Fail to lookup the translated address b5d7c000 >> >> I don't have the root cause yet, I'll keep you updated. > > I suppose it is patch 4? Yes it is. Maxime