From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:52529) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1eKw7K-0001lq-4J for qemu-devel@nongnu.org; Fri, 01 Dec 2017 19:57:21 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1eKw7F-0004uX-VM for qemu-devel@nongnu.org; Fri, 01 Dec 2017 19:57:18 -0500 Date: Fri, 1 Dec 2017 23:37:13 +1100 From: David Gibson Message-ID: <20171201123713.GA2130@umbus.fritz.box> References: <1512127449-11114-1-git-send-email-s1seetee@linux.vnet.ibm.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="NzB8fVQJ5HfG6fxh" Content-Disposition: inline In-Reply-To: <1512127449-11114-1-git-send-email-s1seetee@linux.vnet.ibm.com> Subject: Re: [Qemu-devel] [PATCH v1] spapr.c: Update qemu's maxcpus for pseries machine. List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Seeteena Thoufeek Cc: agraf@suse.de, qemu-ppc@nongnu.org, qemu-devel@nongnu.org --NzB8fVQJ5HfG6fxh Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Fri, Dec 01, 2017 at 04:54:09PM +0530, Seeteena Thoufeek wrote: > Need to adjust the max cpus supported number from error message since > it was conflicting with KVM's. >=20 > Steps to Reproduce: > 1.boot up with > "-smp 64,maxcpus=3D102464,cores=3D8,threads=3D1,sockets=3D8" >=20 > qemu-kvm: Number of SMP CPUs requested (102464) exceeds max CPUs > supported by machine 'pseries-rhel7.4.0alt' (1024) >=20 > 2. On KVM machine it shows >=20 > boot up with > "-m 6G,maxmem=3D300G,slots=3D256 -smp 64,maxcpus=3D1024,cores=3D8,threads= =3D1 > ,sockets=3D128" >=20 > Number of hotpluggable cpus requested (1024) exceeds the maximum cpus > supported by KVM (240) >=20 > It seemed that 1024 was useless since KVM only support 240 so far. > Hence,we need to adjust it to an reasonable value 240. >=20 > Signed-off-by: Seeteena Thoufeek This has been written without adequate thought and investigation. First, in upstream code there's nothing wrong with having different limits in qemu and kernel - the can both vary depending on various factors. Secondly, the 240 limit doesn't come from the kernel upstream - only in RHEL. Third, it doesn't even come from the kernel in RHEL - the downstream qemu lies about the kernel limit. I'm in the process of fixing this correctly, I expect to have something on Monday. > --- > hw/ppc/spapr.c | 1 + > 1 file changed, 1 insertion(+) >=20 > diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c > index 9efddea..c753254 100644 > --- a/hw/ppc/spapr.c > +++ b/hw/ppc/spapr.c > @@ -3691,6 +3691,7 @@ static const TypeInfo spapr_machine_info =3D { > if (latest) { \ > mc->alias =3D "pseries"; \ > mc->is_default =3D 1; \ > + mc->max_cpus =3D 240; \ > } \ > } \ > static void spapr_machine_##suffix##_instance_init(Object *obj) \ --=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 --NzB8fVQJ5HfG6fxh Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQIzBAEBCAAdFiEEdfRlhq5hpmzETofcbDjKyiDZs5IFAlohTPYACgkQbDjKyiDZ s5LephAA2Eg/1fhQBp59jFPu9aFtBTb/M+wKdvEoHP9uWA6of80zMoDcBcF5Xw+K ID4t1Q4wPuEiikj5p14CXDJizOUlm4HHNoN4k4jIGG6I/ipd2zaqZdWadjK/ptYB LqdHD2PCCdeu9Uphi2qsoA89Y/X00Jt1kIcSROQwsY3xhYR9X48DI+KXWEnxdyzZ xL1uIgQ0SIoL2cgSrvou2AFoAmI6i1UBBsx6HvpZq0EPhlt9DAVS51ymwpbk4yb6 SaujqLCwrjXDytnBre9z73KwjaqNdM7Cimkl+zUvavMheCrYKXKpFgqFPRuabwkF Iq5dcyfKsHnGyqfDUHBXLjTQoyDhPYrgFW8XjbFJQ8nXmU2IKfuhtfaFmmOiZuJt jrgRchrHAB4bclAcJI6SCutqZt3BeY1cmlvA1WFKh74/YjrugU9YHIUU9drJz8AF UMxd7n7no/aYxy9qk5+zGRlDVO1e4Ia9DmB26dh++647KWTKm5rUpzK0eFqpEB5B FvkBKxhhNvOCxgwEb+UuI99h3I5k4ZpqFxH0gaSsV9KCUgQfl7es3rAAuxuI/r+F 5MgMDIYnaCw9lttnpRqP+TCdcJCAbnAvlUkXTUpB2pv24CDbN+EsDX6mZUCN/R7/ Jyk8NjeVOd1nBMiT7RfPzvyOtsKgfsPJUvkt37z9YRd5P8dPtm8= =4vbO -----END PGP SIGNATURE----- --NzB8fVQJ5HfG6fxh--