From mboxrd@z Thu Jan 1 00:00:00 1970 From: Konrad Rzeszutek Wilk Subject: Re: I cannot get any message from domU by console / pv_ops domU kernel crashes with xen_create_contiguous_region failed Date: Tue, 22 Dec 2009 09:35:40 -0500 Message-ID: <20091222143540.GB2785@phenom.dumpdata.com> References: <20091221183000.GO16033@reaktio.net> <20091222084214.GR16033@reaktio.net> <1261473615.5965.3829.camel@zakaz.uk.xensource.com> Mime-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: quoted-printable Return-path: Content-Disposition: inline In-Reply-To: <1261473615.5965.3829.camel@zakaz.uk.xensource.com> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xensource.com Errors-To: xen-devel-bounces@lists.xensource.com To: Ian Campbell Cc: Jeremy Fitzhardinge , "xen-devel@lists.xensource.com" , ?????? List-Id: xen-devel@lists.xenproject.org On Tue, Dec 22, 2009 at 09:20:15AM +0000, Ian Campbell wrote: > On Tue, 2009-12-22 at 08:42 +0000, Pasi K=E4rkk=E4inen wrote: > > > (early) [ 0.000000] PCI-DMA: Using Xen software bounce > > buffering for IO > > > (Xen-SWIOTLB) > > > (early) [ 0.000000] Kernel panic - not syncing: > > > <3>xen_create_contiguous_region failed > > >=20 > >=20 > > Did you try cgroup_disable=3Dmemory kernel option?=20 >=20 > I think this is more likely to relate to the failure to initialise > swiotlb due to the failure of xen_create_contiguous_region, leading to = a > panic. IIRC the guest won't be privileged enough to make this call > unless it has PCI passthrough enabled. Not so. You can still make the call even if you don't have PCI passthroug= h enabled. The up call is just to replace MFNs. >=20 > In a pre-pvops kernel the swiotlb would be inactive in a domU unless > specifically requested on the command line but in Jeremy's xen/master > branch it looks like it is unconditionally enabled for dom0 and domU as > a consequence of: > commit 4bc6b1a9dd5d7447af8c3d27c1449f73f5f764ec > Author: root > Date: Thu Nov 5 16:33:10 2009 -0500 > =20 > Enable Xen-SWIOTLB if running in [non-]privileged and disab= le the Xen-IOMMU if an IOMMU is detected. >=20 > On a related note I don't think the xen-swiotlb code should panic() if > it cannot allocate the contiguous region (at least in domU). Chances ar= e I concur. It should also give the error code. I am working on re-writting= that code since the upstream now has some form of registration/de-registration= that we could take advantage off. > if it hasn't got privilege to make the fixups it isn't going to have an= y > devices. >=20 > Ian. >=20 >=20 > _______________________________________________ > Xen-devel mailing list > Xen-devel@lists.xensource.com > http://lists.xensource.com/xen-devel