From mboxrd@z Thu Jan 1 00:00:00 1970 From: annie li Subject: Re: Rebooting domu fails in nfs share exported from another domu on the same dom0 Date: Fri, 18 Jul 2014 16:31:13 -0400 Message-ID: <53C98411.6020404@oracle.com> References: <53C6E24D.7050903@oracle.com> <53C7F088.5070005@citrix.com> <53C8002C.2020501@oracle.com> <20140718185312.GE15947@laptop.dumpdata.com> <53C9761F.3040803@oracle.com> <20140718194334.GK15947@laptop.dumpdata.com> <53C980BE.5040208@oracle.com> <20140718202215.GC14318@konrad-lan.dumpdata.com> Mime-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1"; Format="flowed" Content-Transfer-Encoding: quoted-printable Return-path: In-Reply-To: <20140718202215.GC14318@konrad-lan.dumpdata.com> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: Konrad Rzeszutek Wilk Cc: "xen-devel@lists.xen.org" , =?ISO-8859-1?Q?Roger_Pau_Monn=E9?= List-Id: xen-devel@lists.xenproject.org On 2014/7/18 16:22, Konrad Rzeszutek Wilk wrote: > On Fri, Jul 18, 2014 at 04:17:02PM -0400, annie li wrote: >> On 2014/7/18 15:43, Konrad Rzeszutek Wilk wrote: >>> On Fri, Jul 18, 2014 at 03:31:43PM -0400, annie li wrote: >>>> On 2014/7/18 14:53, Konrad Rzeszutek Wilk wrote: >>>>> On Thu, Jul 17, 2014 at 12:56:12PM -0400, annie li wrote: >>>>>> On 2014/7/17 11:49, Roger Pau Monn=E9 wrote: >>>>>>> On 16/07/14 22:36, annie li wrote: >>>>>>>> Hi >>>>>>>> >>>>>>>> I hit a problem in such scenario: vm1 is running and export nfs se= rvice, >>>>>>>> dom0 mount this nfs, and vm2 is booted in this nfs location. vm1 a= nd vm2 >>>>>>>> are running on the same dom0. >>>>>>>> >>>>>>>> When this bug happens, the data flow is: vm2 blkfront-> vm2 blkba= ck-> >>>>> I am a bit confused here. 'vm2 blkfront -> vm2 blkback'? Did you >>>>> mean 'dom0 blkback'? >>>> Yes, Dom0 blkback. >>>> >>>>>>>> loop -> nfs file -> nfs client -> bridge priv1 -> vm1 vif -> vm1 n= etback >>>>>>>> -> vm1 netfront. >>>>> So both netback and netfront run in the same guest? I think you >>>>> want these two swapped around (netfront -> netback). >>>> No, the netfront in above routine means the one in guest vm1, and this= is >>>> network RX path in vm1. >>> OK, so 'dom0 netback' then. As the netback thread is running in the >>> initial domain? >> Netback thread is running in Dom0 as normal, and the two vms are all >> normal vm, not driver domain. Probably my initial description causes >> some confusion. >> >>> So a revised view is: >>> >>> vm2 blkfront -> dom0 blkback -> loop -> nfs file -> nfs client >>> -> bridge priv1 -> vm1 vif -> dom0 netback -> vm1 netfront >>> >>> So with the grant map (blkfront -> blkback) the source is dom0 >>> and the destination is vm1. >> You mean destination is vm2 here, right? > Yes :-) >> But I am little confused. Blkfront of vm2 sends out request to >> blkback, and the data page is allocated from vm2. So the grant map >> source is vm2, destination is dom0. Anything I missed here? >> >>> For the grant copy, the source is >>> dom0 and the destinatation is vm2 right? (or did I get my src >>> and dst confused?). >> You mean vm1 here, right? > Heh. >> If so, yes, source is dom0, and destination is vm1. >> In grantcopy code, it checks whether the source is from dom0, if >> not, then an error is thrown out. In this situation, the source is >> from vm2 which is grant mapped. > In both cases dom0 is part of the equation. In one > case it is the destination and in another it is the source - both cases > for the same page right? Yes. blkfront->blkback, dom0 is destination netback->netfront, dom0 is the source When doing grantcopy for netback, xen requires the source is dom0. = However, it is vm2 in this case. Thanks Annie > >> Thanks >> Annie >>> >>> _______________________________________________ >>> Xen-devel mailing list >>> Xen-devel@lists.xen.org >>> http://lists.xen.org/xen-devel