From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dario Faggioli Subject: Re: [RFC PATCH 2/3] arch, arm32: add the XEN_DOMCTL_memory_mapping hypercall Date: Mon, 3 Mar 2014 17:35:05 +0100 Message-ID: <1393864505.4058.119.camel@Solace> References: <1393721365-22458-1-git-send-email-avanzini.arianna@gmail.com> <1393721365-22458-3-git-send-email-avanzini.arianna@gmail.com> <53130053.9050801@linaro.org> <1393847789.4058.62.camel@Solace> <53149DDA.2030706@linaro.org> Mime-Version: 1.0 Content-Type: multipart/mixed; boundary="===============3097758558320640454==" Return-path: In-Reply-To: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: Eric Trudeau Cc: "paolo.valente@unimore.it" , Ian Campbell , "stefano.stabellini@eu.citrix.com" , Julien Grall , Tim Deegan , "xen-devel@lists.xen.org" , "julien.grall@citrix.com" , Arianna Avanzini , "viktor.kleinik@globallogic.com" List-Id: xen-devel@lists.xenproject.org --===============3097758558320640454== Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="=-47fmEYKHUfHOeEuQIHCc" --=-47fmEYKHUfHOeEuQIHCc Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable On lun, 2014-03-03 at 16:25 +0000, Eric Trudeau wrote: > > > Right. FTR, xen/arch/x86/domain_build.c, has this (also in > > > construct_dom0): > > > > > > /* DOM0 is permitted full I/O capabilities. */ > > > rc |=3D ioports_permit_access(dom0, 0, 0xFFFF); > > > rc |=3D iomem_permit_access(dom0, 0UL, ~0UL); > > > rc |=3D irqs_permit_access(dom0, 1, nr_irqs_gsi - 1); > > > > > > Do you want a patch to that/similar effect? > >=20 > > Yes. Maybe a bit more smarter than permitting full I/0 caps for dom0. > >=20 >=20 > Our implementation does not require Dom0 access permission in order > for it to grant access permission to a DomU. I suppose it wouldn't hurt > for iomem_permit_access because we allow iomem regions to be mapped > into multiple domains; however, I think the irqs_permit_access call keeps > multiple domains from "owning" the same IRQ. I might be wrong about that= . >=20 As far as I understood it, it is not required here either. And in fact, such permission is not there, and things works for Arianna too. However, it seemed a sane check to have in place (e.g., the x86 implementation does check for that), that's why she's trying to introduce it properly. :-) After all, as far as I remember, you do have something like this: if ( current->domain->domain_id !=3D 0 ) break; don't you? Regards, Dario --=20 <> (Raistlin Majere) ----------------------------------------------------------------- Dario Faggioli, Ph.D, http://about.me/dario.faggioli Senior Software Engineer, Citrix Systems R&D Ltd., Cambridge (UK) --=-47fmEYKHUfHOeEuQIHCc Content-Type: application/pgp-signature; name="signature.asc" Content-Description: This is a digitally signed message part Content-Transfer-Encoding: 7bit -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.22 (GNU/Linux) iEYEABECAAYFAlMUrzkACgkQk4XaBE3IOsR6SQCfetM0PG89rWB3vedPtwNaNkLQ A98An3LTV5BxYFdYnKStJ1ooFOec8ai6 =hjA/ -----END PGP SIGNATURE----- --=-47fmEYKHUfHOeEuQIHCc-- --===============3097758558320640454== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ Xen-devel mailing list Xen-devel@lists.xen.org http://lists.xen.org/xen-devel --===============3097758558320640454==--