From mboxrd@z Thu Jan 1 00:00:00 1970 From: George Dunlap Subject: Re: Xen 4.4 development update, qemu pci hole start address Date: Wed, 9 Oct 2013 11:39:52 +0100 Message-ID: <52553278.7050806@eu.citrix.com> References: <20131008180555.GE2924@reaktio.net> <20131008181315.GF2924@reaktio.net> Mime-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1"; Format="flowed" Content-Transfer-Encoding: quoted-printable Return-path: In-Reply-To: <20131008181315.GF2924@reaktio.net> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: =?ISO-8859-1?Q?Pasi_K=E4rkk=E4inen?= Cc: "xen-devel@lists.xen.org" , Hanweidong , Stefano Stabellini List-Id: xen-devel@lists.xenproject.org On 08/10/13 19:13, Pasi K=E4rkk=E4inen wrote: > On Tue, Oct 08, 2013 at 09:05:55PM +0300, Pasi K=E4rkk=E4inen wrote: >> On Thu, Sep 26, 2013 at 05:47:40PM +0100, George Dunlap wrote: >> http://lists.xen.org/archives/html/xen-devel/2013-05/msg02813.html >> >> "quick" workaround was proposed for Xen 4.3 release, and the "proper" so= lution >> to be done later for Xen 4.4. Is that still the case? Does this issue st= ill need to be resolved? >> >> Quote from the above email/url, Stefano writing: >> >> "this is what I would do: >> >> 1) modify upstream QEMU to start the PCI hole at 0xe0000000, to match >> qemu-xen-unstable in terms of configuration and not to introduce any >> regressions. Do this for the Xen 4.3 release. >> >> 2) for Xen 4.4 rework the two patches above and improve >> i440fx_update_pci_mem_hole: resizing the pci_hole subregion is not >> enough, it also needs to be able to resize the system memory region >> (xen.ram) to make room for the bigger pci_hole" >> >> > Hmm, or maybe this series fixed the issue already properly for Xen 4.3.0? No, this series is still a work-around; see 8/8 of that series: "It's = too late in the release to do a proper fix, so we try to do damage = control." It is fairly likely that there are OS / device combinations = that currently will not work for PCI pass-through, because either the = OS, the driver, or the device won't work when relocated into 64-bit PCI = space. (I think the problem Gordan has been working on might be related, but = I'm not sure.) So yes, good catch -- there should still be an outstanding issue related = to qemu-xen. -George