From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tomasz Wroblewski Subject: Re: Why does xc_map_foreign_range() refuse to map pfns below 1M from a domU Date: Wed, 4 Dec 2013 15:19:54 +0100 Message-ID: <529F3A0A.9010602@citrix.com> References: <1386085913.13256.52.camel@kazak.uk.xensource.com> <1386086974.13256.60.camel@kazak.uk.xensource.com> <529E16B0.5010104@citrix.com> <20131203190741.GB31373@phenom.dumpdata.com> <529F02D5.8090206@citrix.com> <20131204134240.356627e9@mdontu-l> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii"; Format="flowed" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20131204134240.356627e9@mdontu-l> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: =?UTF-8?B?TWloYWkgRG9uyJt1?= Cc: xen-devel@lists.xen.org, Razvan Cojocaru , Ian Campbell List-Id: xen-devel@lists.xenproject.org > Razvan and I are working together to find a solution to this. I took > your patch for a spin and while that code path is taken when invoking > xc_map_foreign_range(), the call still fails with EINVAL. I haven't yet > determined if the call stops in the domU kernel or it reaches xen and > gets terminated there. I've tried this on Ubuntu's 3.8. on top of > XenServer's xen-4.3.1. > Not sure why the patch doesn't work for you (you applied it to domU kernel which ties to map, right?), but before we applied this, the EINVAL was coming from hypervisor's HYPERVISOR_mmu_update in xen_remap_domain_mfn_range(), since the PTE constructed by xen_make_pte was invalid for the other domain. > Thanks, >