From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:33339) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZZZf5-0007R4-Df for qemu-devel@nongnu.org; Wed, 09 Sep 2015 03:19:20 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ZZZf2-00027Z-Ac for qemu-devel@nongnu.org; Wed, 09 Sep 2015 03:19:19 -0400 Date: Wed, 9 Sep 2015 17:19:34 +1000 From: David Gibson Message-ID: <20150909071934.GD17641@voom.redhat.com> References: <1441761736-32030-1-git-send-email-david@gibson.dropbear.id.au> <55EFD0DE.1050001@redhat.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="VMt1DrMGOVs3KQwf" Content-Disposition: inline In-Reply-To: <55EFD0DE.1050001@redhat.com> Subject: Re: [Qemu-devel] [PATCH] spapr: Reduce advertised max LUNs for spapr_vscsi List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Thomas Huth Cc: lvivier@redhat.com, pbonzini@redhat.com, qemu-ppc@nongnu.org, qemu-devel@nongnu.org --VMt1DrMGOVs3KQwf Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Wed, Sep 09, 2015 at 08:25:34AM +0200, Thomas Huth wrote: > On 09/09/15 03:22, David Gibson wrote: > > The implementation of the PAPR paravirtual SCSI adapter currently > > allows up to 32 LUNs (max_lun =3D=3D 31). However the adapter isn't re= ally > > designed to support lots of devices - the PowerVM implementation only > > ever puts one disk per vSCSI controller. >=20 > Do you know how many LUNs are advertised by PowerVM? Well, what do you mean by "advertised". AFAIK from the point of view of the guest, the number of LUNs is advertised per-target, not per controller. When I say "advertised" here, I'm meaning what the controller advertises to the qemu SCSI core, and thereby to the option parsing code. > > More specifically, the Linux guest side vscsi driver (the only one we > > really care about) is hardcoded to allow a maximum of 8 LUNs. >=20 > So what about changing the vscsi driver in Linux instead to support more > LUNs? Doesn't help for existing guests. Basically what I'm trying to achieve is for qemu to reject up-front configurations that are unlikely to actually work in the guest. --=20 David Gibson | I'll have my music baroque, and my code david AT gibson.dropbear.id.au | minimalist, thank you. NOT _the_ _other_ | _way_ _around_! http://www.ozlabs.org/~dgibson --VMt1DrMGOVs3KQwf Content-Type: application/pgp-signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iQIcBAEBAgAGBQJV792GAAoJEGw4ysog2bOSW3gP/RUkhVYg6JeNqURUZMvr1ORm FYXJvf5NARzeKSctq3u58Xj4cgkKEFGEv+b7DXo5cFJVXlwiQMMpTxHxl3n2UGdN Qsc1AZ/gqoJuCG8GX9G+gpvOAzXGb6HtVhEKgyVYkBJXCqCHqALXa3n1ntiQpF42 R/TlSxXBpfsEibWDMrBInp642qsEVHzqLTtpRvXwDEXUAf4gvbOxpWG9dFZRh8qj 2gZQnceBq4J6ZH15I95nuIvdbLJll95HEYQuCAMK+YyTANEkFw23gpCbqv8AHl/+ FVN7HpKOy8PTGUqDLrf71aMoCSjIM0DCwdZEkqtkjzZ/co6dUvQagGzK1PuV9COi 12qZVRcDzJAFMlimhln4L2MhIE4UgCDNrsaCA9nm09eJHqQ58j4f/hd8vUIUvLVs BiQKJhsEj5jHfIJ4m4BtrbVoouf0rKwFRLjr10OXKkSJjiObZzdnV4As7Ezj6b1N uoMbk8mm/ph4k/RhZMzNrcfYtb7OdTsPVvOILigCtFCMuO1mMoa6+oS03EUjTk45 bWpr/M0yQ60xrEFkoR8S3qPN5vvue8gk5pVMzPl1LXirZTTYI6QO7qBlNZuEedeE 8pn2RhBNnO3e4571Ebr91WemhI9s+zP/A+IDN9zbJMGwejF4+Yyb4ex2ne1V0U6x 17moGV/5nlOg3hjMEL9n =LhCx -----END PGP SIGNATURE----- --VMt1DrMGOVs3KQwf--